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Con riferimento al concetto di edilizia circolare, intesa come riduzione degli impatti ambientali del processo edilizio nelle sue varie fasi attraverso il riuso e la riqualificazione, lo studio del ciclo di vita assume una rilevanza sempre maggiore. La riqualificazione è intesa come approccio sostenibile al miglioramento prestazionale del patrimonio costruito che ne consente l’incremento della vita utile, in confronto al più radicale ed impattante intervento di demolizione e ricostruzione. In particolare, gli aspetti prestazionali che attualmente assumono maggiore rilevanza sono quelli relativi alla riabilita-zione sismica delle strutture ed alla riqualificazione energetica dell’involucro e degli impianti. Si trat-ta tuttavia di interventi invasivi ed economicamente rilevanti che difficilmente un privato affronta in mancanza di specifici input normativi ed economici. Per questo, la riqualificazione dell’edilizia pub-blica ed in particolare del social housing, può assumere un ruolo guida del settore edilizio. Lo studio della letteratura ha rivelato diversi approcci al problema, fondamentalmente basati sullo studio del ci-clo di vita del bene edilizio e dei suoi impatti a livello ambientale, ovvero di Life Cycle Assessment (LCA) e delle sue ricadute economiche, il Life Cycle Cost Assessment (LCCA). Nell’ambito del progetto di ricerca europeo PRO-GET-ONE, coordinato dall’Università di Bologna, è in corso di studio un approccio alla riqualificazione sismica ed energetica di edifici esistenti di social housing basato sulla realizzazione di un esoscheletro esterno che migliora sia le prestazioni sismiche che quelle energetiche in modo integrato, creando inoltre un plusvalore per l’incremento delle superfici abitative. L’approccio integrato alla riqualificazione prestazionale della deep renovation porta alla identificazione di nuove strategie di pianificazione e gestione del ciclo di vita dell’immobile basate sulla identificazione di indicatori di prestazione di tipo ambientale LCA ed economico LCC che han-no lo scopo di valutare le alternative di intervento in particolare bilanciando le due strategie di recu-pero, sismica ed energetica. With reference to the concept of circular construction, intended as the reduction of the environmental impacts in the building process through reuse and rehabilitation actions, the study of the life cycle is continuously increasing its relevance. The rehabilitation is considered a sustainable approach to im-prove the performances of building stocks, enabling the extension of the service life, compared to the more radical and impactful intervention of demolition and reconstruction. In particular, the most relevant aspects related to building performance concern the seismic rehabilitation of structures and the energy retrofitting of envelopes and building services. However, these are invasive and econom-ically relevant interventions, that a private investor barely faces without specific regulations or eco-nomic inputs. For this reason, the rehabilitation of public buildings and, particularly of public hous-ing can assume a leading role in the building sector. The study of the scientific literature has revealed different approaches to this issue, primarily based on the study of the life cycle and the environmen-tal impacts of the built assets, i.e. the Life Cycle Assessment (LCA) with its economic consequenc-es, the Life Cost Assessment (LCC). The European research project PRO-GET-ONE, coordinated by the University of Bologna, studies an innovative approach to the seismic and energy rehabilita-tion of public housing, based on the realization of an eso-skeleton for the combined improvement of the seismic and energy performances of the buildings, that also generates a surplus value as a con-sequence of the increased living surfaces. This integrated approach to the building performance re-habilitation of the deep renovation leads to new strategies of life cycle planning and management based on the identification of environmental performance indicators with the goal of evaluating in-tervention alternatives, balancing the two – seismic and energy – renovation strategies.

The rate of aerobic Ca2+ transport is limited by the rate of the H+ pump rather than by the Ca2+ carrier. The kinetics of the Ca2+ carrier has therefore been studied by using the K+ diffusion potential as the driving force. The apparent Vmax of the Ca2+ carrier is, at 20 degrees C, about 900 nmol (mg of protein)-1 min-1, more than twice the rate of the H+ pump. The apparent Vmax is depressed by Mg2+ and Li+. This supports the view that the electrolytes act as noncompetitive inhibitors of the Ca2+ carrier. The degree of sigmoidicity of the kinetics of Ca2+ transport increases with the lowering of the temperature and proportionally with the concentration of impermeant electrolytes such as Mg2+ and Li+ but not choline. The effects of temperature and of electrolyte do not support the view that the sigmoidicity is due to modifications of the surface potential. Rather, they suggest that Ca2+ transport occurs through a multisubunit carrier, where cooperative phenomena are the result of ligand-induced conformational changes due to the interaction of several allosteric effectors with the carrier subunits. In contrast with La3+ which acts as a competitive inhibitor, Ruthenium Red affects the kinetics by inducing phenomena both of positive and of negative cooperativity. The Ruthenium Red induced kinetics has been reproduced through curve-fitting procedures by applying the Koshland sequential interaction hypothesis to a four-subunit Ca2+ carrier model.

Rat liver mitochondria take up aerobically large amounts of divalent cations in the absence of exogenous phosphate. The electron spin resonance (ESR) spectrum of matrix Mn2+ reveals the presence of two components: one, a sextet signal, corresponding to hydrated Mn2+; another, a spin exchange signal, attributed either to Mn2+ binding to specific high-energy membrane sites or to complexes of Mn2+ with inorganic phosphate. Identification of the spin exchange signal with a Mn-Pi complex is favoured by the evidence that the spin exchange signal is observed at pH 7.5 but not at pH 6.5 in the absence of exogenous Pi, but at both pH 7.5 and 6.5 in the presence of exogenous Pi. On the other hand both in the absence or presence of exogenous Pi inhibition by N-ethylmaleimide of Pi transport, abolishes the spin exchange signal. This signal is again observed when Piis generated in the matrix, in the presence of N-ethylmaleimide, by ATP hydrolysis, and again abolished by oligomycin. Finally, addition of uncouplers results in a very slow disappearance of the signal. The amount of Mn2+ participating in the spin exchange signal has been calculated to be in the range of 50–60 nmol × mg protein −1. This amount is compatible with the amount of endogenous Pi present or generated in average mitochondrial preparations. The ESR spectrum obtained by superimposing the spectra of Mn3(PO4)2 precipitate and hydrated Mn2+, in appropriate concentrations and ratios, resembles closely the ESR spectrum during aerobic Mn2+ uptake in mitochondria. The band width of the spin exchange signal of Mn3(PO4)2 is not constant and varies between 40 and 22 mT depending on the state of aggregation of the complex. The kinetics of aggregation can be followed in solution as a function of the concentration of Mn2+, Pi and of pH. Similar kinetics can also be followed during aerobic Mn2+ uptake by controlling the rate of Mn2+ influx. The present data support the previous proposal [Pozzan et al. (1976) Eur. J. Biochem. 71, 93–99] that the spin exchange singal is essentially due to a Mn3(PO4)2 precipitate in the mitochondrial matrix.

Delta approximately muH has been determined in steady state mitochondria by measuring the magnitude of delta pH on the distribution of acetate and of deltapsi on the distribution of K+, tetraphenylphosphonium, Ca2+, Sr2+ and Mn2+. (1) The matrix concentration of divalent cations has been calculated from the total cation uptake, from the increase of matrix volume and from the ESR sextet signal of Mn(H2O)L2+. The [cat2+]i based on osmotic data is about five times higher than that based on ESR measurements. The [cat2+]i based on total uptake is much higher than that based on osmotic data at low cation/protein ratios. (2) In the presence of 10 mM acetate the maximal deltapsi on Ca2+ is about 130 mV and on Sr2+ is 95 mV. Deltapsi on Mn2+ is 91 or 109 mV, according to whether [cat2+-a)i is calculated from ESR or osmotic data. Under the same conditions, deltapH is about 60 mV. Hence delta approximately muH on divalent cations is between 151 and 190 mV. (3) Deltapsi on K+, in valinomycin treated mitochondria with 10 mM acetate or 2 mM Pi, drops from 200 mV, at low [K+]0 to almost zero parallel to the increase of [K+]0. DeltapH is 30 mV at low [K+]0 and about 42 mV at 600 muM K+. Hence delta approximately muH drops from 22m mV lower values with the increase of [K+]0. (4) Maximal deltapsi on triphenylmethylphosphonium is 140 mV. (5) When delta approximately muH is measured simultaneously on divalent cations and on K+, the values on K+ tend to approach those on Ca2+ while those on Sr2+ are about 50 mV lower. (6) It is concluded that the steady state mitochondrial energy potential is equivalent to a delta approximately muH between 150 and approx. 190 mV.

Digitalization is transforming the real estate and construction (REC) sector and a key feature of this transformation is Building Information Modelling (BIM) - the virtual representation of all building-related information. By enabling the creation of digital twins of real buildings, BIM generates opportunities to do many things in new and better ways including education and training. Specifically, BIM offers the possibility of data rich virtual environments in which project-based learning experiences can be designed. Researchers at Tallinn University of Technology, Tampere University and the University of Bologna are currently developing a prototype BIM-enabled Learning Environment (BLE) with the intention of providing more realistic, immersive and integrated learning experiences. In addition to the BLE platform itself, pilot learning modules are being created to demonstrate the potential for this approach and, to determine their effectiveness, evaluation tools are being designed. This research investigates existing, applicable evaluation models and derives an evaluation model and tools specifically adapted for the immersive project-based learning experiences provided through the BLE. A literature review was conducted to identify existing evaluation models. A comparative content analysis approach was employed to identify their specific use cases, implementation requirements, advantages and disadvantages for deployment within the BLE context. The BLE pilot learning modules were analysed in terms of their defining characteristics and the key features of evaluation models applicable to them were identified. The identified features were then integrated to derive a new evaluation model and a corresponding set of evaluation tools considering the contemporary principles of Engineering Pedagogy. The research results include: 1) Defining characteristics of the BLE pilot learning modules and the challenges these pose for evaluation. 2) Existing evaluation models and their applicability to the immersive project-based learning experiences of the BLE. 3) An outline of the evaluation model and appropriate evaluation tools for the BLE learning modules. An evaluation model together with supporting evaluation tools are proposed that will assist educators and trainers in evaluating the impact of their activities for effective engineering education. This research also serves as a guide for the development of future BLE learning modules and for evaluating their effectiveness. publishedVersion

Purpose – This paper is based on research addressing quality of construction schedules. The paper aims to structure a Schedule Health Assessment method and present it as a means to carry out the evaluation of construction schedules. Design/Methodology/Approach – The development of the Schedule Health assessment method can be characterised as constructive research. The structuring of the method is based on analysis of factors forming the overall quality of construction schedules. The method has been tested in a proof of concept study. This comprised a case study in which four master schedules developed by junior production managers were evaluated using the Schedule Health assessment method. Findings – It is possible to construct a method for the quality evaluation of construction schedules. Research Limitations/Implications – The completed testing is still rather limited since it is based merely on experiences of junior production managers with a single case. Practical Implications – The Schedule Health assessment method can in a useful manner make the quality evaluation of construction schedules easy to approach and effective process. Originality/Value – This research has produced a novel method for the quality evaluation of construction schedules. publishedVersion

The relevance of systems thinking as a competence of significance for project managers has been pointed out particularly in publications by project management associations such as IPMA and APM. Particularly it is complex projects where systems thinking can have an important role. Those disclose the need for holistic systems approaches where viable project systems can be designed. As a project planning solution, the resultant project system represents an overall structure to be used when the project logic is communicated and various project stakeholders are engaged. The project system can capture the principles of significance and associated processes for explaining the key elements of targeted project performance. As a project management solution, the project system can help to understand the behavior of project in question. The explained systems approach has gained rather limited presence in research addressing construction project management. This paper shall present main results of a research effort, which included development of a solution, termed as integrative project system, for designing actual project systems for collaborative construction projects, which are seen as important vehicles for reaching smart built environments. Here collaborative construction projects are understood as endeavors where key partners are closely operating together with shared risks and opportunities for reaching highest possible performance and benefit. For this type of construction projects, the actual practices and processes are rather poorly understood, often leading to disappointments. The resultant solution explains the structure of project system for collaborative construction projects (principles, key elements and their structuring). It can be used as starting point for designing needed project systems. The gained results are based on an action research that was carried out in co-operation with representatives from public and private sectors. publishedVersion

La strategia proposta per la mitigazione dei principali rischi per la sicurezza dei lavoratori presenti nei cantieri della ricostruzione del sisma dell’Emilia del 2012 è basata sulla pianificazione dell’emergenza e sulla programmazione delle fasi di cantiere. Il metodo di programmazione proposto è quello dei diagrammi tempo/spazio, integrato con la contestuale definizione dei rischi con il metodo “Hazard Mapping”.

Si considerano i rischi presenti nei cantieri della ricostruzione delle aree colpite dal sisma dell’Emilia del 2012. Il rischio dovuto a crolli improvvisi e a cadute dall’alto a causa di eventuali scosse sismiche, anche di assestamento, è considerato dal punto di vista della sicurezza degli operatori di cantiere. La strategia proposta per la mitigazione dei rischi per la sicurezza dei lavoratori è basata sulla pianificazione dell’emergenza e sulla programmazione delle fasi di cantiere. Il metodo di programmazione proposto è quello dei diagrammi tempo/spazio, integrato con la contestuale definizione dei rischi con il metodo del Risk Mapping. Il programma operativo delle opere che ne deriva, quale ad esempio il programma delle demolizioni, consente di definire per le aree di lavoro i fondamentali rischi presenti in ogni fase costruttiva, come ad esempio quello dei collasso intempestivo e quello di caduta dall’alto, e permette quindi la tempestiva azione preventiva e protettiva.

L’Italia continua a vantare una frequenza degli infortuni nel settore delle costruzioni, in rapporto ai lavoratori impegnati, inferiore alla media europea. Questa confortante situazione è però contraddetta dai dati relativi agli infortuni mortali. Per indagare questo fenomeno è stata svolta una operazione di benchmarking con il settore delle costruzioni tedesco ed inglese, con un particolare approfondimento della struttura procedurale e normativa della Gran Bretagna. La normativa inglese per la sicurezza dei cantieri, nonostante sia il recepimento della Direttiva 92/57/CEE, comporta una organizzazione per la sicurezza del processo edilizio del tutto specifica e particolare rispetto a quella italiana e di altri paesi europei, ma porta a dati statistici del tutto positivi. La comparazione di Germania e Gran Bretagna con l'Italia conferma come la prevenzione degli infortuni debba basarsi sulla valutazione dell’intero sistema lavorativo, iniziando in primo luogo dall’analisi dei comportamenti adottati dai soggetti coinvolti. È chiara la correlazione con una molteplicità di fattori: aspetti socioeconomici; aspetti culturali; aspetti organizzativi; aspetti tecnici; ed in primis la formazione del singolo lavoratore.