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Hospitals represent the most energy-intensive buildings in most of the World, mainly because of strict requirements for micro-climatic control and high energy needs for equipment. Thus, the effective energy design and/or retrofit of these buildings can yield huge energy, environmental and economic benefits. In this frame, the study investigates the energy retrofit of a hospital building, i.e., the “D” Pavilion of the “A. Cardarelli” hospital facility in Naples (South Italy). The building is modeled in EnergyPlus and the energy model is calibrated by comparison against measured data, provided by an annual experimental campaign. Hence, in order to address building energy retrofit, a rigorous cost-optimal analysis is conducted by coupling EnergyPlus and MATLAB®. The investigated energy retrofit measures (ERMs) are addressed to the energy systems and to the exploitation of renewable energy sources. ERMs for the building envelope are excluded because they are not effective for the considered case study. The optimization allows to explore a comprehensive domain of retrofit scenarios, and thus, finally, robust cost-optimal solutions are found in correspondence of different discount rates. These solutions yield substantial reductions of primary energy consumption, global cost and polluting emissions with payback periods around 4 years.

The distinction between fibrotic and viable myocardium is a key issue in patients with coronary artery disease and left ventricular dysfunction. Metabolic imaging with positron emission tomography (PET) and labeled tracers, along with the study of myocardial perfusion, is now available to identify hibernating myocardium. However, PET imaging of myocardial metabolism is a high-cost and time-consuming technique, and requires an on-site cyclotron. The aim of this study is to test the reliability of dobutamine echocardiography (DE) compared with PET imaging, for the identification of hibernating myocardium. In 16 patients, scheduled for myocardial revascularization, left ventricular shapes were divided in eight segments both for echocardiographic and nuclear study evaluation. All patients underwent a technetium 99m MIBI single-photon emission tomography stress-rest study of perfusion, a fluorine-18-labeled deoxyglucose (FDG(/PET study of metabolism, and a DE test (baseline, at a 5 micrograms/kg/min infusion of dobutamine for 8 minutes and at a 10 micrograms/kg/min dose for additional 8 minutes). Neither myocardial ischemia nor arrhythmia occurred during the DE test. Baseline echocardiograms showed 90 segments with wall motion abnormalities: wall motion impairment was decreased or reversed in 33 of 90 segments; it remained unchanged in 57 of 90 segments. In 32 of 33 segments considered viable on the basis of DE and in 21 of 57 segments with unchanged kinesis, some degree of FDG was detected. Thus, sensitivity and specificity of DE compared with nuclear studies was 60% and 97% respectively. Moreover, a good correlation and agreement (kappa = 0.51) between DE and the presence of FDG were found. We conclude that DE is a safe and reliable test for the screening of hibernating myocardium in patients with chronic coronary artery disease and left ventricular dysfunction.

A novel methodology is proposed in order to support the cost-optimal design of building envelope’s thermal characteristics and space conditioning systems in presence of an enhanced simulation-based model predictive control (MPC) for heating and cooling operations. The cost-optimal solution is identified by running a main mono-objective genetic algorithm (GA) that allows to minimize the global cost for space conditioning over building lifecycle. Each solution investigated by the GA represents a building thermal design combined with the MPC of space conditioning systems. In order to define the MPC strategy, the main mono-objective GA launches two secondary bi-objective GAs that optimize the heating and cooling operations, respectively. These secondary GAs perform a Pareto optimization by minimizing operating cost for space conditioning and thermal discomfort. They provide the optimal values of hourly set point temperatures for heating and cooling systems, with a day-ahead planning horizon, by considering the forecasts of weather conditions and building use. The optimal control strategy is detected based on needs and wills of users, who set a minimum level of thermal comfort to be fulfilled. The three employed GAs are implemented by coupling MATLAB® (optimization engine) with EnergyPlus (building performance simulation tool). For testing purposes, the methodology is applied for the thermal design of a new multi-zone residential building located in Naples (Southern Italy). It produces potential savings of 35.4 kWh/m2a as for primary energy consumption, and of around 7’000 € as for global cost, by ensuring the same satisfying comfort level, compared to standard approaches for building thermal design and space conditioning systems’ control.

During the last decade, in the Mediterranean area, during the warm season, there is an increasing demand of cooling energy in domestic and small commercial sectors, generally satisfied by electrically-driven units. This trend has involved an increase of the power generation capacity of electric utilities and a summer peak load of electric energy consumption with the related problem of electric black-out. This problem has been the driving force to an increasing interest in small scale polygeneration systems fuelled by natural gas, especially in the South of Europe. These energy conversion systems are based on a prime mover that can drive in different ways (mechanically, electrically, thermally) electric generators and/or electric heat pump, absorption heat pumps, desiccant wheels, … allowing a wide range of operating conditions to match thermal (heating and cooling) and electric end-user requirements. In particular, in this paper, attention is paid to the description of a test facility, located in Southern Italy, designed and built to carry out experimental analysis on a small scale polygeneration system based on a natural gas-fired Micro- CHP and a hybrid HVAC (Heating, Ventilation and Air Conditioning) system equipped with a desiccant wheel. The MCHP supplies thermal power, recovered by engine cooling and exhaust gas, to the regeneration of the sorption material of the desiccant wheel and electric power for Air Handling Unit, AHU, self consumptions (fans, pumps, …), to drive the electric chiller and finally for the external units (computers, lights…). The hybrid HVAC system can also operate in traditional way, interacting with separate “production” systems (electric grid and gas-fired boiler). In this paper the first experimental results considering different operating modes are reported.

The mismatching between the predicted and the operational performance of buildings designed to be nearly zero-energy underlines the importance to study the post-occupancy behavior, to understand if the building-HVAC system is capable to meet the variable conditions even due to the progressive climate change. The paper proposes a discussion about the operational performance of an existing nearly zero-energy building in the Mediterranean climate, during the heating and cooling seasons. The monitoring shows that the required electrical power is always lower than the nominal one, also because the external conditions are not extreme as the design ones. In the colder days, the difference in the required power is −21%. In summer, there is a delay of two hours between the external maximum temperature and the maximum required power. However, the monitored power is usually higher than the nominal one, with a maximum value of +11%. Considering all proposed combinations for the design calculation, it is demonstrated that the real performance cannot be predicted during the design, because indoor and external conditions influence the dynamic behavior of the building-HVAC system.

Studying fluid dynamics in an operating room has a key role to achieve the right air quality conditions inside, for different purposes, and thus the patient comfort, the correct air distribution (distinguishing infected or not infected patients), the recirculation of contaminants and so on. One of the most relevant parameters to take into account is the age of air, defined as the mean time that a particle takes to go from an inlet point to the considered point. This parameter can be employed to evaluate the air change effectiveness inside the room. In this study, the effect of two distinct arrangements of recovery grids for the air outflow and two different positions of the lighting systems are considered. The computational fluid dynamics software ANSYS Fluent is used to solve the partial differential equations governing the mass transport, air velocity components, turbulence, energy, and age of air in order to evaluate the changes in terms of age of air and air changes effectiveness in critical zones of an octagonal operating room. Inside the room, the presence of four people of medical staff and the patient is considered too. The results show critical differences among the distinct considered arrangements, highlighting how relevant the operating room fluid dynamics is. The lowest mean age of air (136 s) and the highest air changes effectiveness (108 %) among the simulated configurations occur in the case of vertical return grids and vision lamp on patient bed and when the xy vertical plane located at the center of the room is considered

An up-to-date review of more than 100 research papers about green building rating tools is proposed, with a view to what is changed or must be changed, also following the new requirements due to the recent pandemic. The review organizes current literature in the matter of rating systems in four different groups: rating systems’ comparison papers, case studies, the proposition of new rating systems, possible integration of rating systems into other design tools for buildings. The research papers have been analyzed to underline the main investigated aspects in rating systems, how to improve the rating systems for enlarging the sustainability assessment, and how much the level of certification reflects the green, sustainable, healthiness, and indoor environmental quality features of buildings. Moreover, possible improvements of the weighting systems are here showed, in the rating systems’ method, and some new aspects for the sustainability assessment are suggested. As regards the pillars of sustainability, the main neglected points are structural safety, vulnerability to calamitous events, compatibility with local culture and history. Moreover, the indoor environmental quality and the flexibility/adaptability of livable environments are underestimated in the current rating systems. These issues have emerged strongly during the COVID-19 pandemic and have become a priority.

Thermal ablation has a primary role in cancer treatment due to its minimal invasiveness, and the improvement of this technique is fundamental in order to avoid incomplete ablation or healthy tissues ablation. In this work, modified bioheat models based on Pennes’ or LTNE bioheat models are employed in a simplified two-layer spherical model made up by a hepatocarcinoma tumor bounded by a healthy liver tissue. Improvements are done by including variable porosity or perfusion into either LTNE-based or Pennes-based models, accounting for local properties variations. Other modifications in common to both models, like blood flow arrest induced by necrosis, or employing an equivalent external thermal dose as the heat source term, are introduced too. Numerical results are presented in terms of temperature fields, thermal damage evolution, and the resulting ablation size. The latter, that represent the main outcome from a thermal ablation procedure, is compared with experimental measurements performed on an in vivo clinical study referred to hepatocellular carcinomas in human beings. From these comparisons, it is shown that the modified porous media-based model provides a very good agreement, with lesion sizes differences which are no higher than 9.1%; on the other hand, the modified Pennes’ equation allows to a slight underestimation of the achieved temperatures due to a too much high heat sink effect. The information derived from the present study would be very helpful to improve thermal ablation modeling by employing a LTNE bioheat porous model that accounts for aspects like variable porosity and other model improvements.

COVID-19 pandemic has caused an economic crisis, and also the building sector has suffered consequences. Indeed, an increase in the building energy consumption, mainly in the residential sub-sector, was registered, due to higher energy use. European Union has enacted a strategic plan to combat this crisis by promoting environmental sustainability and giving a key role to the building sector. This study provides an overview of the implementation state from EU countries, of the European policies in terms of building energy efficiency and draws attention to the adopted financial programs and incentives to promote an energy-efficient built environment. It is shown that more than 70% of Member States have transposed the EU Energy Performance of Building Directives and all of them have activated plans or programs to finance the building energy renovation, mainly in the residential sector. A focus is made on the Italian case, by considering the recently introduced tax deduction of 110% (divided into a number of annual rates) that promotes specific energy efficiency measures for existing buildings, in the vein of new requirements provided by the Directive EU 844/2018. In this investigation, three residential buildings are selected, and, by employing both semi-stationary and dynamic approaches, a critical analysis of several passive and active energy efficiency measures is performed. The variability of climatic conditions and building markets are considered in energy and economic evaluations: the building case studies are located in different Italian climatic regions and have different construction ages. Considering the energy, environmental and economic indicators, it is shown how the new Italian funding program can boost the diffusion of energy efficiency interventions which imply the best energy performance, and not the best cost/benefit ratio. The study points out achieved goals, criticalities, and new perspectives after years of energy policies in Europe.

Cognitive reserve (CR) delays cognitive decline due to neurodegeneration. Heterogeneous evidence suggests that education may act as CR in Dementia with Lewy Bodies (DLB). No data, however, are currently available on the role of occupation as proxy of CR in this neuropathology. Thirty-three patients with probable DLB were retrospectively included. We performed regression analyses models (TFCE p< 0.05) and seed-based interregional correlation analyses (p= 0.001, FWE-corrected at cluster-level) with brain metabolism. We aimed at exploring the relationship between brain metabolic connectivity, as assessed by FDG-PET, in the relevant resting-state networks and CR proxies (education, 6-levels occupation, and the specific O*Net occupational profiles). Education modulates executive (ECN), attentive (ATTN) and posterior default mode (PDMN) networks in the highly educated DLB subjects, as shown by an increased metabolic connectivity, acting as a compensatory mechanism. High scores of the 6-levels occupation scale were associated with a decreased connectivity in the anterior default mode (ADMN) and high visual network (HVN), suggesting brain reserve mechanisms. As for the specific O*Net occupational profiles, these modulated ADMN, PDMN, ATTN, ECN, HVN and primary visual network (PVN) connectivity according to different neuroprotection mechanisms, namely neural reserve and compensation against neurodegeneration. This study highlights the relevance of life-long occupational activities at individual level in the neural expression of compensatory and neuroprotective mechanisms in DLB.

Graphical abstract, Highlights • University buildings must be safe, secure and suitable for an “in-presence” education. • Architectural and technological retrofits are necessary to face the COVID-19. • HVAC-related measures anti-contagion need studies in both time and space domains. • A numerical model of a University building, calibrated against measurements, is proposed. • The design of refurbishment is performed by coupled numerical methods, BES and CFD., The proposed investigation is aimed at providing useful suggestions and guidelines for the renovation of educational buildings, in order to do University classrooms safe and sustainable indoor places, with respect to the 2020 SARS-CoV-2 global pandemic. Classrooms and common spaces have to be thought again, for a new “in-presence” life, after the recent worldwide emergency following the spring 2020 pandemic diffusion of COVID-19. In this paper, starting from a real case study, and thus the architectural and technological refurbishment of an Italian University building (Campobasso, South Italy, cold climate), with the aims of improving the classrooms’ quality and safety, a comprehensive approach for the retrofit design is proposed. By taking into account the necessary come back to classrooms starting, hopefully, from the next months (Autumn 2020), experimental studies (monitoring and investigations of the current energy performances) are followed by the coupling of different numerical methods of investigations, and thus building performance simulations, under transient conditions of heat transfer, and computational fluid dynamics studies, to evidence criticalities and potentialities to designers involved in the re-thinking of indoor spaces hosting multiple persons, with quite high occupancy patterns. Both energy impacts, in terms of monthly and annual increase of energy demands due to higher mechanical ventilation, and indoor distribution of microclimatic parameters (i.e., temperature, airspeed, age of air) are here investigated, by proposing new scenarios and evidencing the usefulness of HVAC systems, equipment (e.g., sensible heat recovery, without flows’ contamination) and suitability of some strategies for the air distribution systems (ceiling squared and linear slot diffusers) compared to traditional ones.

The optimal control of the HVAC system in the nearly zero energy buildings (nZEBs) can be considered as a challenge. Indeed, the lack of data given by monitored data does not allow understanding what are the implications of different strategies on thermal comfort and energy consumptions. This paper determines an approach for the evaluation of the management of the heating system in an existing educational nZEB. The aim is to understand how the energy efficiency of the heating system is sensitive to controls strategies and the important role played by the control systems. The test lecture rooms on KU Leuven Ghent Technology Campus (Belgium) have been chosen as case study. A deep analysis, starting from an in-field monitoring, was carried out during the winter period of 2019, in order to assess the actual operation and the energy use of building systems under real conditions. Then, a building energy simulation (BES) model of the building and its systems was developed and calibrated against the real monitoring data. Control strategies of the heating system are simulated and compared to the current configuration. The simulation results show that strategies based on a definition of a heating curve for the boiler can reduce the comfortable time (−23%). Controlling the temperature inside the storage tank as a function of the outdoor temperature together with the control on the activation of the air handling unit result in an energy savings from 32% to 46%, with a correspondent increase of comfort time in the period from 0.6% to 3.4% compared to the baseline scenario, depending to the relationship between the external temperature and water temperature inside the water storage tank.

Buildings account for around one third of World energy consumption and polluting emissions, thus their energy retrofit is crucial aiming at reducing the human impact on the environment. In this context, worldwide, public grant policies and stringent requirements have been adopted to promote energy efficiency in the building sector. This study proposes a comprehensive analysis to drive the energy retrofit of building neighborhoods by examining energy efficiency measures involving envelope components, heating, ventilating and air conditioning systems, photovoltaics. The effects of the creation of a local energy community that shares the photovoltaic production are taken into account too. Finally, the Italian “Superbonus 110%” public grant policy is considered, and some insights are given. More in detail, the analysis aims at minimizing at the same time the primary energy consumption and the global cost, satisfying both the public and the private stakeholders. It makes use of different software: CADMapper® and SketchUp® for modeling the geometry of the neighborhood; DesignBuilder® for realizing the first raw energy model; EnergyPlus to refine the energy model and to perform dynamic energy simulations; MATLAB® to post-process the results of the simulations. As case study, an existing neighborhood located in Naples (Italy) is investigated and three suboptimal solutions are proposed: nZEB solution, cost-optimal solution and utopia solution. Sensible reductions in energy consumption and global cost can be achieved in presence of public grants, i.e., up to 69.2 kWh/m2a and 153.6 €/m2, respectively.

Quantification of amyloid PET studies is most accurate if regions of interest (ROIs) are not affected by the presence of cerebrospinal fluid. Patients with high amyloid load often have great atrophy, therefore, the use of atlas-based ROIs, instead of patient specific anatomy, can underestimate amyloid load, leading to a bias. Traditionally, this can be overcome only using MR anatomical sequences, which are burdensome and might not be ideal to be performed for each patient in the clinical routine. In this work, we propose to overcome this issue by using a method based on deep learning. As CT scans provide anatomical information, even at the very low doses used for PET attenuation correction, we propose the use of such a scan, together with the PET one, for a U-NET based segmentation. The approach achieves a median DICE score of 77% on a validation cohort of N=20 patients, even when using only N=14 patients in the training dataset. A dedicated data augmentation strategy is used, and the individual contribution of each modality is analyzed. We find that the joint effect of PET and CT is beneficial (median DICE: PET only 73.0%, CT only 74%). A near perfect correlation with MR-based quantification was also found.

The paper introduces a new semi-probabilistic methodology for the definition of energy fragility curves suitable for a macro-classification of building stock inspired to and coupled with the widely adopted method of seismic fragility curves. The approach is applied to the reinforced concrete residential buildings of the Italian stock. Starting from a classification according to the climatic zone and the construction period, some reference buildings in terms of building envelope typologies have been defined and simulated by means of dynamic modeling tools. Then, cumulative distributions of the probability that the primary energy consumption for heating was comparable with certain threshold values are defined according to the climatic conditions expressed with the heating degree days, which constitute the intensity measure for the fragility curves. Finally, by focusing on the interaction points between structural and energetic aspects, it is shown how these curves can be useful for decision-makers with regards to definition of importance and or the level of intervention to be made to the building envelope for improving its seismic safety and the energy quality. Indeed, non-integrated interventions are more expensive and less efficient.

An analysis of design configurations is proposed for a 5 kW residential space heating split system comparing several low GWP refrigerants (R32, R290, R1234yf, R1234ze, XL41, XL55) as potential alternatives to the most common refrigerants actually used (R410A, R407C, R134a). By means of an ad-hoc model, the system performance has been estimated for several geometrical configurations among those possible according to the current compressor and heat exchangers technology. The configurations complying with geometric and thermodynamic constraints are discussed in terms of opposing criteria: economic (set-up and total costs), thermodynamic (COP) and environmental ones (LCCP). With R32 it is possible to define design configurations that are able to reach the best energetic performances for fixed set-up costs. In the range of low set-up costs solutions, R32 and R410A design options are able to work with the same performance. Particularly, R32 can reach the minimum LCCP value as propane with 15% lower total costs.

The energy transition of neighborhoods towards nearly zero energy buildings (nZEBs) is fundamental to promote sustainability. The study deals with this issue by proposing a methodology to optimize energy retrofit through the exploitation of solar energy by photovoltaics. Part of a neighborhood in the city of Naples (South Italy) is investigated. The coupling between EnergyPlus and MATLAB® is used for energy modelling, simulations and retrofit optimization through a smart research method, performing a comprehensive analysis of heating, cooling and electric loads. A Pareto multi-objective approach is applied to minimize both energy consumption and global cost in order to optimize the solar energy exploitation and to achieve the nZEB standard while ensuring cost-effectiveness. Different retrofit scenarios for building envelopes and energy systems are investigated. Two optimal retrofit solutions are identified. One pursues the minimization of the neighborhood's energy impact ensuring a PEC reduction from 116.8 kWh/m2a to 66.3 kWh/m2a with discounted payback (DPB) of around 10 years. The other solution maximizes the cost-effectiveness yielding a PEC around 83.7 kWh/m2a with a DPB of only 4 years. The outcomes offer deep insights into the potentials of energy transition for neighborhoods and guidelines for the implementation of multi-generation energy systems as well as to address public energy policies.

Carbon dioxide two-phase flow characteristics are different from those of conventional refrigerants, due to the CO2 particular thermodynamic and transport properties obtained by working at high reduced pressures. Moreover, the use of peculiar heat transfer surfaces such as grooves and internal fins are often preferred to enhance the boiling heat transfer performance. This paper collects CO2 flow boiling heat transfer coefficient data from different independent databases available in scientific literature, regarding both smooth and enhanced geometries and a wide range of operative conditions, that are typical of refrigeration systems and heat pumps. The database for enhanced tubes covers internal diameters from 0.8 to 8.92 mm, saturation temperatures from -30 to +20 °C, imposed heat fluxes from 1.67 to 60 kW/m2 and mass velocities from 75 to 800 kg/m2s, collecting more than 800 points. Heat transfer data for smooth and enhanced surfaces under the same conditions are collected, in order to measure the enhancement and to correlate it to the geometry augmentation. The assessment of quoted prediction methods explicitly developed for carbon dioxide is finally carried out, with a proposal for a correction factor.

The study aims at providing comprehensive insights into the influence of the climatic stress on building heating demand. The examined case studies are two residential buildings, representative of the Italian existing and newly-built stocks, respectively. Building energy performance is simulated by comparing a standard normative approach with a tailored accurate one using EnergyPlus. The comparison is performed for several locations (i.e., 63) to consider all typical Italian climates. A global sensitivity analysis is performed to identify the most influential climatic parameters and to investigate the correlation between heating demand and HDD (heating degree days). The findings show that a base temperature of 18 °C in HDD assessment provides higher determination coefficient compared to 20 °C, and that HDD should consider also solar radiation and/or latitude to achieve a better correlation. Finally, climatic stress curves are provided to assess thermal energy demand and running cost for heating operation as a function of HDD for both the existing and the newly-built building.

Objective Neuroinflammation is considered a key driver for neurodegeneration in several neurological diseases, including amyotrophic lateral sclerosis (ALS). SOD1 mutations cause about 20% of familial ALS, and related pathology might generate microglial activation triggering neurodegeneration. 11 C-PK11195 is the prototypical and most validated PET radiotracer, targeting the 18-kDa translocator protein which is overexpressed in activated microglia. In this study, we investigated microglia activation in asymptomatic (ASYM) and symptomatic (SYM) SOD1 mutated carriers, by using 11 C-PK11195 and PET imaging. Methods We included 20 subjects: 4 ASYM-carriers, neurologically normal, 6 SYM-carriers with probable ALS, and 10 healthy controls. A receptor parametric mapping procedure estimated 11 C-PK11195 binding potentials and voxel-wise statistical comparisons were performed at group and single-subject levels. Results Both the SYM- and ASYM-carriers showed significant microglia activation in cortical and subcortical structures, with variable patterns at individual level. Clusters of activation were present in occipital and temporal regions, cerebellum, thalamus, and medulla oblongata. Notably, SYM-carriers showed microglia activation also in supplementary and primary motor cortices and in the somatosensory regions. Interpretation In vivo neuroinflammation occurred in all SOD1 mutated cases since the presymptomatic stages, as shown by a significant cortical and subcortical microglia activation. The involvement of sensorimotor cortex became evident at the symptomatic disease stage. Although our data indicate the role of in vivo PET imaging for assessing resident microglia in the investigation of SOD1-ALS pathophysiology, further studies are needed to clarify the temporal and spatial dynamics of microglia activation and its relationship with neurodegeneration.

The main purpose of this study is to evaluate, based on experimental data, the potential of pre-cooling the ventilation air based on ground-to-water heat exchanger, coupled with an intermediate water-to-air exchanger, during the summer period. The case study for this investigation is an existing nearly zero energy building located in Benevento, a middle-size city of South Italy with typical Mediterranean climate. Measurements of several performance parameters with four different HVAC possible configurations are shown as well as monitoring of energy uses and indoor microclimatic conditions in order to verify if comfort conditions inside the building are guaranteed together with the achievement of ‘nearly zero energy target’. Indeed, the study intends to assess the interaction between building and power grid and evaluate the temporal correspondence between building load and PV generation with hourly time step. The discussion about the hourly energy balance serves as reference to export or improve management and design strategies in regions with comparable climate conditions.

The necessity to predict building energy performance assumes a predominant role today. Present regulations in energy matter introduce pressing objectives for the energy requalification of buildings. Within spring 2020, EU Member States must adopt the European Directive 2018/844, which focuses the attention on present buildings. It establishes new obligations to retrofit the existing building stock. Solutions to improve building energy performance and to achieve economic, energy, and environmental benefits become mandatory, requiring robust and reliable procedures for energy modeling and simulation. The present study will show the importance of considering a non-standard occupant profile in energy performance simulations. The investigated edifice is a typical residential building in Naples (southern part of Italy, Mediterranean climate), built during the sixties and seventies. For the energy retrofit of the building, the most common refurbishment interventions in the Neapolitan building stock will be assessed for energy, economic and emissions savings, and thus new thermal insulation and replacement of windows. Firstly, the results will be analyzed by taking into account a standard-use profile of the occupants. Secondly, the possible wrong behaviors of users will be examined, to compare an “energy-intensive” model with the standard retrofitted model. The impact on building energy demand of the following actions will be analyzed: more energy-intensive use of the electric and lighting systems, the opening of the windows during the activation hours of the heating/cooling systems, the modification of the thermostat setpoint, the deactivation of the shading systems. The study shows a considerable increase in energy demand, following the wrong behavior of the occupants, which affects the economic convenience of the refurbishment investment. The energy retrofit is economically and energetically feasible for a standard building occupation, but sometimes wrong habits can reduce the convenience, if energy-intensive behaviors occur. This work will show that, when the numerical building model of a common building refurbishment is realized and when the cost-benefits analysis is performed, the uncertainty in occupant behavior cannot be neglected.

The green wall is an engineered technology for stormwater management and climate change mitigation at the urban level. At the building scale, these energy efficiency measures are suitable for improving indoor comfort conditions and for reducing energy needs. Several guidelines are available about vertical greening systems, but these propose design parameters and performance evaluation criteria, often incomparable. In order to facilitate the implementation of proper technical standards, this paper proposes a critical review of more recent scientific investigations. All parameters for the design optimization are discussed as well as the achievable social and private benefits by taking into consideration the type of study (numerical or experimental), the climate conditions, the analysis period, all technical requirements of the green layer as well as of the back wall. The review underlines that a multi-criteria design approach is needed for green vertical systems. Thus, the paper is concluded with a SWOT analysis, evidencing “strengths”, “weaknesses”, “opportunities” and “threats”. The analysis shows that the highlighted benefits will acquire greater relevance considering the increase in global temperatures and the growing need to redevelop densely built urban centers, while some negative aspects may be filled in the future with a deeper preparation of designers and careful choice of materials. The review paper shows, therefore, drivers and barriers occurring designing and implementing green walls.

This study offers deep insights into the link between climatic stress and building heating performance. Two representative Italian residential buildings – existing and newly-built, respectively – are investigated by predicting heating demand for 63 locations, covering all typical national climates. Two simulation software are used – i.e., TERMUS® and EnergyPlus –, to compare a standard semi steady-state approach with a more accurate dynamic one. The comparison enables to understand the influence of the climatic stress on different levels of building modeling/simulation. Notably, the semi steady approach can provide reliable outcomes (close to the dynamic one) for existing buildings in cold climates. Then, a sensitivity analysis is conducted to investigate the correlation between climatic parameters and yearly heating demand, showing that the heating degree day index does not provide a complete explanation of such demand. Indeed, it does not take into account latitude and/or solar radiation, whose influence is not negligible. Therefore, a novel heating stress index is proposed, including normalized heating degree day and latitude. Its expression is optimized through a Pareto approach to ensure the best fitting/regression of yearly heating demand for both building typologies. The achieved determination coefficient (R2) is 0.990 for the existing building, 0.995 for the newly-built one. Finally, climatic stress curves are achieved to predict heating demand and related running cost as a function of the proposed index, providing a user-friendly but reliable tool to forecast building heating needs.

The study provides a methodological approach for designing energy refurbishment measures of buildings, enabling to understand the uncertainty of using numerical modelling and the real impacts due of adopting some energy efficiency technologies. The case study is a University building of the centre of Italy, and the reference scenario has been supported by various in-situ surveys, investigations and evaluations of the indoor comfort. Collected data, together with a comparison with energy bills, has allowed a proper calibration of a numerical model simulated by means EnergyPlus. All this phase is described in this paper, while a second part will discuss the energy retrofit and the building energy optimization. © 2019 The Authors. Published by Elsevier Ltd.

Nowadays, the Nearly Zero Energy Buildings (NZEBs) represent the new target from 2019 onwards. The present study is focused on a single-family house (called BNZEB), placed in south Italy and specifically designed for a Mediterranean climate. The “Benevento” Nearly Zero Energy Building (that is why the name is “BNZEB”) is built with the purpose to be, at the same time, a research laboratory, suitable for testing and measuring energy demands, renewable energy conversion, indoor environmental quality and other aspects of performances in a realistic context. More in detail, firstly the BNZEB is presented and described; then, the early results of a monitoring campaign are shown with the purpose to characterise the energy performance of this building during the summer season and verify the effectiveness of chosen design solutions. For this reason, the daily energy balance is proposed with the aim to evidence the impact of solar production and electric storage on building energy consumptions. It is really important the presentation and the discussion about the monitoring results because, very often, the real performance does not coincide with the expected one and further optimizations are needed. Subsequently, a numerical model of the case study building, suitable for performing transient energy simulations, is used to compare the BNZEB building with other buildings: (a) one representative of the constructive standard established by Italian law; (b) a second one typical of the not-refurbished buildings stock of the city. The aim of this last part is to understand how much the BNZEB's energy performances are better compared to reference buildings during the summer season. Finally, the replicability of BNZEB design in Mediterranean cities, like Lisbon, Montpellier, Madrid, Seville and Athens is evaluated.

The present work concerns the energy retrofit of a public educational building at the University of Molise, located in Termoli, South Italy. The study provides a comparison of the results obtained by different dynamic simulations of passive strategies to improve thermal comfort and energy behavior of the building during the summer regime. Firstly, the building model was calibrated against historical consumption data. Then, a subsequent step involves the technical-economic analysis, by means of building performance simulations, of energy upgrading scenarios, specifically, cool roof and green roof technologies for the horizontal opaque envelope and thermal insulation, vented fa&ccedil, ade, and phase change materials&rsquo, applications for the vertical opaque envelope. Improving the indoor thermal comfort and reducing the thermal energy demand during summertime through innovative solutions will be the primary objective of the present study. The energy efficiency measures are compared from the energy, emissions, costs, and indoor comfort points of view. Phase Change Materials applied to the inner side of the external walls are analyzed in depth and, by varying their melting temperature, optimization of design is performed too. This innovative material, with a melting temperature of 23 &deg, C and a freezing temperature of 21 &deg, C, determines the reduction of summer energy consumption of 11.7% and the increase of summer indoor comfort of 215 h. Even if consolidated, other solutions, like the cool roof, green roof, thermal insulation, and vented fa&ccedil, ade induce improvements in terms of summer energy saving, and the percentage difference compared to the basic building is less than 2%. For this case study, a Mediterranean building, with construction characteristics typical of the 1990s, traditional passive technologies are not very efficient in improving the energy performance, so the investigation focused on the adoption of innovative solutions such as PCMs, for reducing summer energy demand and improving indoor thermal comfort.

The first part of this study provided a discussion about the methodological approach for designing energy refurbishment measures of buildings. The case study is a building owned by University of Molise, in Campobasso, a cold Italian city. The reference scenario is a numerical model built after deep investigations, and thus surveys, questionnaires, documents and experimental measurements on the real building. Then, a calibrated energy model was presented. In this second part, starting from the calibrated model, some energy retrofit measures have been implemented. The obtained results allow to discuss two key points for researches in matter of energy refurbishment of buildings: a) the importance of using validated models to simulate the present performance; b) the environmental benefits and the economic implications of a deep energy refurbishment. © 2019 The Authors. Published by Elsevier Ltd.

Many strategies are under investigation to reduce the environmental impact of the building stock. Among them, the implementation of optimal operation strategies of the HVAC (heating, ventilating and air conditioning) systems plays a fundamental role because it can produce substantial energy-economic savings and increment of thermal comfort. In this vein, a weather-data-based control framework is here proposed to provide optimal heating operation strategies easily applicable to a huge number of buildings. It works by coupling EnergyPlus and MATLAB® to run a multi-objective genetic algorithm and proposes a novel approach for multi-criteria decision-making. This latter addresses characteristic days (i.e., average cold days, average days and average hot days) of weather data files with the aim to provide monthly heating strategies that ensure the best compromise between running cost and thermal discomfort. As case studies, the proposed framework is applied to a residential building, representative of the Italian building stock from 1961 to 1975. In order to cover most of the Italian territory, four different cities are considered: Palermo (climatic zone B), Naples (C), Florence (D) and Milan (E). The achieved cost reduction is included between 6% (Milan) and 34% (Palermo), while the thermal comfort is not penalized. Finally, the framework provides practical indications ready to be easily applied to the Italian residential stock to achieve a significant and widespread improvement of energy performance. © 2019 Elsevier Ltd

The investigation of bioheat transfer is a difficult issue because it entails a mixture of many mechanisms to take into account, such as thermal conduction in tissues, convection and blood perfusion, metabolic heat generation, vascular structure, changing of tissue properties depending on physiological condition and so on. This topic has a key role to predict accurately the temperature distribution in tissues, especially during biomedical applications. In this paper, different bioheat transfer models are resumed and compared. The biological tissue is modelled as a porous sphere and liver tissue properties are used. Governing equations are averaged over a Representative Elementary Volume (REV) of the living tissue. Transient bioheat equations based on models like, for example, Pennes model, Local Thermal Non-Equilibrium equations (LTNE model), are employed. In the employed equations, radiative heat transfer is also considered. Governing equations with the appropriate boundary conditions are solved with the finite-element code COMSOL Multiphysics®. The effects of hyperthermia on the living tissue are included with a source term in the tissue energy equation. Results are presented in terms of temperature profiles in the biological tissue; the aim is to appreciate differences due to the various bioheat models.

In this paper, new saturated critical heat flux (CHF) values at medium-to-high saturation temperatures are presented for an aluminum multi-minichannel test section. Among the possible working fluids, R134a and the low GWP refrigerants R1234yf and R1234ze have been selected. The aluminum heat sink used as test section is made up of seven minichannels, each of them 2 mm wide, 1 mm high and 35 mm long, thus resulting in an internal equivalent diameter of 1.33 mm. All tests were carried-out by taking into account the influence of the mass flux and the saturation temperature. The first was set from 150 up to 350 kg/m(2) s, while the latter was varied from 25 degrees C up to 75 degrees C. The results in the form of diagrams and boiling curves show that the experimental CHF significantly increases with mass velocity, whereas a general CHF drop with the saturation temperature is detected, especially for lower mass fluxes. Finally, the agreement of the present database with some well-known CHF correlations is also tested. In order to perform valuable comparisons, the experimental points in which the uncertainty in the operative parameters was superior to a chosen threshold have been excluded from the statistics. The results show that the equations of Anwar et al. [28] and Callizo et al. [25] best predict the experimental values. (C) 2016 Elsevier Masson SAS. All rights reserved.

The recast version of the Energy Performance of Buildings Directive (2010/31/EU) proposes a comparative methodology aimed at defining the energy performance of buildings “with a view to achieving cost-optimal levels”. Really, how can the cost-optimal technologies be detected? Moreover, how can the most proper packages of energy efficiency measures be chosen in order to obtain the cost-optimality? This paper would provide answers to these questions, by proposing a new methodology for the evaluation of the cost-optimality, by means of the multi-objective optimization of energy performance of buildings and indoor thermal comfort. The optimization procedure is developed by means of the coupling between MatLab and EnergyPlus, by implementing a genetic algorithm, and it allows the evaluation of profitable and feasible packages of energy efficiency measures applied to buildings. Then, following the adoption of these packages, the global cost over the lifecycle of the building is calculated, in order to identify the cost-optimal solution. After the presentation of the methodology, the developed method is proposed for the optimization of the energy retrofit of an existing building. Furthermore, the method can be applied also for new architectures, by considering reference buildings.

We studied the relationships between coronary anatomy, perfusion and metabolism in myocardial segments exhibiting transient and persistent perfusion defects on stress/rest 99Tcm-MIBI single photon emission tomography in 35 patients (31 males, 4 females, mean age 56 ± 7 years) with a previous myocardial infarction. Quantitative coronary angiography and assessment of myocardial perfusion reserve and glucose metabolism were performed within 1 week of one another. Perfusion was assessed by SPET after the intravenous injection of 740 MBq of 99Tcm-MIBI at rest and after exercise. Regional myocardial glucose metabolism was assessed by position emission tomography at rest (200 MBq of 18F-2-deoxyglucose, FDG) after an overnight fast with no glucose loading. All 35 patients exhibited persistent perfusion defects consistent with the clinically identified infarct site, and 27 (77%) also showed various degrees of within-infarct FDG uptake; 11 patients developed exercise-induced transient perfusion defects within, or in the vicinity of, 15 infarct segments and resting FDG uptake was present in 10 of these segments (67%). Five patients also showed exercise-induced transient perfusion defects in nine segments remote from the site of infarct: resting FDG uptake was present in six of these regions (67%). Finally, nine patients had increased glucose uptake in non-infarcted regions not showing transient perfusion defects upon exercise—testing and perfused by coronary arteries with only minor irregularities. Our results confirm the presence-of viable tissue in a large proportion of infarct sites. Moreover, FDG uptake can be seen in regions perfused by coronary arteries showing minor irregularities, not necessarily resulting in detectable transient perfusion defects on a MIBI stress scan. Since the clinical significance of such findings is not clear, further studies should be conducted to assess the long-term evolution of perfusion, function and metabolism in non-revascularized patients of those remote areas which are apparently normally perfused, but show abnormal fasting FDG uptake after myocardial infarction. Such studies may have important implications for the management of post-infarct patients, as the preservation of coronary vasodilator reserve and myocardial metabolism in remote myocardium may be seen as an additional goal in the treatment of such patients. © 1998 Lippincott-Raven Publishers.

Dopo aver sinteticamente presentato il quadro normativo attualmente in vigore per l’efficienza energetica in edilizia, la memoria approfondisce le principali problematiche connesse alla progettazione integrata del retrofit energetico di edifici con destinazione d’uso complessa, quali le strutture ospedaliere. Coniugare gli standard di efficienza energetica vigenti, con le norme e le leggi relative alla progettazione delle strutture sanitarie, rappresenta infatti una delle più grandi sfide per il processo di efficientamento energetico del patrimonio edilizio nazionale. Nell’edilizia ospedaliera, in particolare, la progettazione di interventi per il risparmio energetico deve avvenire nell’ottica irrinunciabile della progettazione integrata del sistema edificio-impianti poiché, da un lato, il controllo del microclima deve essere operato sia dall’impianto che dall’involucro, dall’altro, è altresì necessario selezionare i sistemi HVAC in funzione delle loro necessità gestionali e manutentive, principalmente in modo da non interferire con il ciclo di funzionamento continuo dell’edificio. Pertanto, gli impianti devono non solo garantire condizioni di comfort termo-igrometrico e qualità dell’aria per gli occupanti, ma è richiesto che soddisfino anche esigenze di processo legate alle diverse attività mediche previste, considerando che, in molti ambienti, il rispetto di taluni requisiti minimi (efficienza di filtrazione, quantità di ventilazione di aria esterna, condizioni di pressione dell’ambiente) è la condizione necessaria allo svolgimento dell’attività stessa. In questo lavoro, tali aspetti saranno approfonditi attraverso la presentazione di un esempio di diagnosi e riqualificazione energetica di un edificio adibito ad ospedale, presentando come caso studio il lavoro svolto dagli stessi autori per il Day-Hospital del Complesso Ospedaliero “G. Pascale”, situato a Napoli. Per questo edificio, incrociando procedure sperimentali e numeriche, è presentata la caratterizzazione energetica dello stato attuale attraverso la costruzione di un modello numerico e la simulazione del rendimento energetico del sistema edificio-impianto per la valutazione energetica, ambientale ed economica di possibili interventi di retrofit, mediante azione sia sull’involucro edilizio che sugli impianti termotecnici installati. Partendo dai risultati dall’analisi di convenienza tecnico-economica per il caso studio presentato, nella parte conclusiva la memoria suggerisce spunti di riflessione per la selezione di interventi idonei alla riqualificazione di edifici adibiti ad ospedali, nell’ottica di un funzionale ed efficace controllo microclimatico.

This paper presents experimental results for local heat transfer coefficients, adiabatic frictional pressure gradients and two-phase flow regimes with the low-GWP refrigerant R-1234ze(E), compared to Hydro-Fluoro-Carbon refrigerant R-134a in the same conditions. In particular the results refer to an experimental investigation carried out in a circular smooth tube of 6.00 mm of inner diameter, for saturation temperatures between −2.9 °C and 12.1 °C, mass fluxes between 146 and 520 kg m−2 s−1 and heat fluxes between 5.0 and 20.4 kW m−2. These experimental results are compared to those for R-134a at the same operating conditions. Moreover, an assessment of predictive methods is provided for local heat transfer coefficients and frictional pressure gradients; also a direct comparison of flow regimes visualizations for R-1234ze(E) with a flow pattern map available in literature is presented.

We examined 17 angina-free patients with left ventricular dysfunction, referred for surgical decision-making, who presented with no or few signs and symptoms of myocardial ischemia according to treadmill stress test. On cardiac catheterization they were affected by severe multi-vessel coronary artery disease; the mean left end-diastolic pressure of this population was 26.3 +/- 5.5 mm Hg (mean +/- SD) and their mean ejection fraction was 27.6 +/- 4.9% (mean +/- SD). They all were investigated for the presence of viable myocardium by the combined assessment of cardiac perfusion and metabolism using single photon emission tomography with [99mTc] labelled hexakis-2-methoxy-isobutyl-isonitrile [99mTc]MIBI/SPET) and positron emission tomography with [18F]-2-fluoro-2-deoxy-D-glucose ([18F]FDG/PET), respectively. Patients were considered for coronary surgery when [18F]FDG was detectable in at least two cardiac segments with wall motion abnormalities and perfusion defects. Nine patients were operated on, six were medically treated and two were scheduled for heart transplantation. We recorded no in-hospital mortality. At a mean follow-up of 28.4 +/- 9.8 (mean +/- SD) months all surgical patients were alive and their NYHA functional classes have improved, except in one case. Among the patients refused for bypass surgery, three are in stable conditions, three have worsened clinical statuses and two died while waiting for heart transplantation. In conclusion, for patients with bypassable coronaries, left ventricular dysfunction and lack of angina, successful coronary revascularization may be predicted by the presence of viable myocardium demonstrated with positron emission tomography.

The CO2 and propane blends are an interesting alternative to solve technical and safety issues related to the use of pure CO2 or pure hydrocarbons. These mixtures of pure fluids are environmentally friendly and have a large glide, that affects remarkably heat transfer. In this paper a review of works and predictive methods on flow boiling of wide-boiling mixtures is first presented. Experiments during flow boiling in a smooth horizontal tube with an internal diameter equal to 6.00 mm of CO2 and propane mixtures (with 83.2/16.8% and 70.0/30.0% in mass concentrations) are reported. The experiments are related to the following operating ranges: mass fluxes from 200 to 350 kg m−2 s−1, heat fluxes from 10 to 20.2 kW m−2, temperatures of the mixture from 6.9 to 14.0 °C in the whole range of vapor qualities. An assessment of predictive methods based on the present and independent databases is reported.

This paper presents the results of an experimental analysis which compares in terms of energetic performances the refrigeration capacity control obtained by means of a variable-speed compressor with the on/off control deriving from a classical thermostatic device. The compressor considered is semi-hermetic reciprocating and is a component of a vapour compression refrigeration plant subjected to a commercially available cold store. The compressor working with the fluids R22, R507 and R407C and designed for a revolution speed corresponding to the compressor supply current nominal frequency of 50 Hz, has been tested varying the frequency in the range 30–50 Hz. In this range, the most suitable working fluids proposed as substitutes of the R22 as the R407C (R32/R125/R134a 23/25/52% in mass), the R507 (R125/R143A 50/50% in mass) and the R417A (R125/R134a/R600 46.6/50/3.4% in mass) have been tested. The results show that, using the R407C, it is possible an average an electric energy consumption about 12% smaller when an inverter is employed to control the compressor refrigeration capacity instead of the thermostatic control which imposes on/off cycles on the compressor, working at the nominal frequency of 50 Hz. So the R407C confirms its superiority in comparison with the R417A and R507; only the R22 shows a better performance.