6,931 research outputs found

    Energy Retrofit of a Historic Building Using Simplified Dynamic Energy Modeling

    Get PDF
    Energy retro-commissioning of historical buildings is an important challenge that implies both historic-artistic and technological aspects concerning the improvement in energy efficiency and comfort. A critical analysis of each possibility is essential in order to preserve the balance between efficiency and architecture. The research focuses on a historical building owned by ANCE (Associazione Nazionale Costruttori Edili), situated in Rome in the Nomentano district. Retrofitting hypothesis were made in order to improve HVAC systems, building's envelope and building's management, always respecting its architectural features. An energy audit has been done in order to evaluate the possibilities. The first step of the study consisted of a measure campaign conducted by Avvenia to know more about the actual use of the building. Next, a dynamic simplified energy modeling of the building has been built using the software Archi Energy. This allowed to preview the effect of modifications on the HVAC and envelope systems. Although starting from an original medium energy performance, simulations showed that it would be possible to reach a further reduction of energy needs by making simple changes in the management/controls domain and, with higher costs, by upgrading envelope components. This study shows that a correct approach can lead to both relevant energetic results and the conservation of architectural characteristics of historical buildings

    Retrospective analysis of the correlation between the facial biotype and the inclination of the upper canine cusp axis to the occlusal plane

    Get PDF
    Permanent maxillary canines are the second most frequently impacted teeth and the prevalence of this clinical condition is estimated to be 1-2% in the general population. The diagnosis of maxillary canine impaction should be based on both clinical and radiographic examinations. The aim of this study was to evaluate the presence of a correlation between the facial biotype and the inclination of the upper cusp axis. A correlation between the total radicular length of the lateral incisors was also evaluated, by comparing the side of impaction with the healthy side. Twenty three patients with a diagnosis of unilateral upper cusp impaction were recruited. For each patient, dental casts and radiographic material (panoramic radiographs and lateral cephalograms) were examined. Statistical analyses were done with Spearman's rank correlation coefficient or Spearman's rho (V). X-ray examinations demonstrated that canine impaction was associated to other dental anomalies (32% of the sample). The mean S angle measurements were 22.9° ± 4.1°, and mean values of the T angle were 34.7°± 4.0°. The mean distance “d” value was 14.6 mm ± 1.2 mm. The mean values of the angle between the upper cusp axis and the perpendicular-to-Fh plane were 20.8 °± 2.6°. Among the 23 subjects recruited, 5 showed values included in the range 25°-45° and 1 an inclination > 45°. The results obtained in the present study demonstrate a significant inverse correlation between the MM angle and the inclination of the upper cusp axis to the perpendicular-to-Fh plan

    On-glass optoelectronic platform for on-chip detection of DNA

    Get PDF
    Lab-on-chip are analytical systems which, compared to traditional methods, offer significant reduction of sample, reagent, energy consumption and waste production. Within this framework, we report on the development and testing of an optoelectronic platform suitable for the on-chip detection of fluorescent molecules. The platform combines on a single glass substrate hydrogenated amorphous silicon photosensors and a long pass interferential filter. The design of the optoelectronic components has been carried out taking into account the spectral properties of the selected fluorescent molecule. We have chosen the [Ru(phen)2(dppz)]2+ which exhibits a high fluorescence when it is complexed with nucleic acids in double helix. The on-glass optoelectronic platform, coupled with a microfluidic network, has been tested in detection of double-stranded DNA (dsDNA) reaching a detection limit as low as 10 ng/ÎĽL

    Basin scale assessment of landslides geomorphological setting by advanced InSAR analysis

    Get PDF
    An extensive investigation of more than 90 landslides affecting a small river basin in Central Italy was performed by combining field surveys and remote sensing techniques. We thus defined the geomorphological setting of slope instability processes. Basic information, such as landslides mapping and landslides type definition, have been acquired thanks to geomorphological field investigations and multi-temporal aerial photos interpretation, while satellite SAR archive data (acquired by ERS and Envisat from 1992 to 2010) have been analyzed by means of A-DInSAR (Advanced Differential Interferometric Synthetic Aperture Radar) techniques to evaluate landslides past displacements patterns. Multi-temporal assessment of landslides state of activity has been performed basing on geomorphological evidence criteria and past ground displacement measurements obtained by A-DInSAR. This step has been performed by means of an activity matrix derived from information achieved thanks to double orbital geometry. Thanks to this approach we also achieved more detailed knowledge about the landslides kinematics in time and space

    Digital documentation of fortified urban routes in Pavia (Italy): territorial databases and structural models for the preservation of military ruins

    Full text link
    [EN] The analysis of the fortified routes in the city of Pavia (Italy) clarifies the adaptation of the medieval capital in the historical politics of the Mediterranean, where the evolution of the defensive system till the Spanish bastioned walls (sixteenth century) identifies the updating of the Lombard tradition to the practices of modern military architecture. Their defensive structures survive in the urban design of the contemporary city, in the configuration of infrastructures and urban aggregates, reflecting the consequences of the great processes of their dismantling (from 1905). The comparison between historical investigations and the current ruins, fragmented into disconnected portions between the historical bastions and the monumental gates, shows a picture of abandonment of the military structures that generates repeated collapses and emerging risk factors towards the surrounding densified urban context. The experimentation of military architectural approaches of documentation at the urban scale, developed by the research laboratory DAda Lab. of University of Pavia, defines an analysis process through the digital representation of the urban remains that is suitable for the preservation of the survived city walls and the enhancement of their fortified identity. The application of different 3D LiDAR systems for morphological acquisition promotes an integrated digitation process of scansets on the fortified system controlled at the urban metric scale: the experimentation applies the use of a mobile real time scanner for the digital tracking of historical routes, on which to implement the georeferencing of detailed static scanworlds, integrated in correspondence of Bastions and Monumental Gates. The optimization of architectural data density and the integration between data contribute to finalize a 3D territorial database predisposed to the architectural modelling of volumes and scenarios of structural instability of the military ruins, defining a virtual framework of widespread knowledge for the historical conservation and urban prevention of the fortified systemDe Marco, R.; Galasso, F.; Malusardi, C. (2020). Digital documentation of fortified urban routes in Pavia (Italy): territorial databases and structural models for the preservation of military ruins. Editorial Universitat Politècnica de València. 349-356. https://doi.org/10.4995/FORTMED2020.2020.11518OCS34935

    Social Network and Content Analysis: An Integrated Methodology to Investigate a Global Community Evolution

    Get PDF
    The present study describes an Integrated Methodology developed combining Social Network and Content Analysis approaches, to investigate the organizational mechanisms responsible for the creation of Social Capital within Communities. The methodological integration is proposed to overcome one of the main limitations of Social Network Analysis (SNA): the analysis of the content of the information flows and the organizational and cultural aspects of their exchanges. The methodological framework was able to differentiate the “ties” among community members on the basis of the subject matter of the information flows. It showed its reliability for Project-oriented Virtual Communities to discover and draw the development path of their projects, from the new idea generation to the project outcome delivery, through the content “tagging” of the information flows. It is suitable to describe the main characteristics of a project-oriented community, useful and effective to monitor the processes developed within the community

    The relationships between vitamin K and cognition: a review of current evidence

    Get PDF
    Vitamin K is a fat-soluble nutrient discovered in 1935 and its role in blood coagulation has been thoroughly explored. In recent years, studies conducted in vitro and on animals highlighted vitamin K involvement in brain cells development and survival. In particular, vitamin K seems to have an antiapoptotic and anti-inflammatory effect mediated by the activation of Growth Arrest Specific Gene 6 and Protein S. Moreover, this vitamin is involved in sphingolipids metabolism, a class of lipids that participate in the proliferation, differentiation, and survival of brain cells. An altered expression in sphingolipids profile has been related to neuroinflammation and neurodegeneration. This review stems from a growing interest in the role of vitamin K in brain functions, especially in cognition, also in view of an expected increase of prevalence of Alzheimer's disease and other forms of dementia. It collects recent researches that show interesting, even though not definitive, evidence of a direct correlation between vitamin K levels and cognitive performance. Moreover, vitamin K antagonists, used worldwide as oral anticoagulants, according to recent studies may have a negative influence on cognitive domains such as visual memory, verbal fluency and brain volume. The aim of this review is to analyze the evidence of clinical studies carried out up to date on the relationship between vitamin K intake and cognitive performances. The involvement of vitamin K antagonists (VKAs) in declining cognitive performances is also addressed separately

    Piezoelectric effect and electroactive phase nucleation in self-standing films of unpoled PVDF nanocomposite films

    Get PDF
    Novel polymer-based piezoelectric nanocomposites with enhanced electromechanical properties open new opportunities for the development of wearable energy harvesters and sensors. This paper investigates how the dissolution of different types of hexahydrate metal salts affects β-phase content and piezoelectric response (d33) at nano-and macroscales of polyvinylidene fluoride (PVDF) nanocomposite films. The strongest enhancement of the piezoresponse is observed in PVDF nanocomposites processed with Mg(NO3)2·6H2O. The increased piezoresponse is attributed to the synergistic effect of the dipole moment associated with the nucleation of the electroactive phase and with the electrostatic interaction between the CF2group of PVDF and the dissolved salt through hydrogen bonding. The combination of nanofillers like graphene nanoplatelets or zinc oxide nanorods with the hexahydrate salt dissolution in PVDF results in a dramatic reduction of d33, because the nanofiller assumes a competitive role with respect to H-bond formation between PVDF and the dissolved metal salt. The measured peak value of d33reaches the local value of 13.49 pm/V, with an average of 8.88 pm/V over an area of 1 cm2. The proposed selection of metal salt enables low-cost production of piezoelectric PVDF nanocomposite films, without electrical poling or mechanical stretching, offering new opportunities for the development of devices for energy harvesting and wearable sensors

    Empirical insights on the nature of synergies among HRM policies - an analysis of an ethics-oriented HRM system

    Get PDF
    In the last years, several HRM scholars have theoretically support the idea that the policies bundled in an HRM system present synergistic effects. Surprisingly, empirical studies about those synergistic effects are scarce, and their results unstable. As a result, some critical voices in the HR field are questioning the idea of synergies among HR policies, and calling for more research which does not take them for granted. Addressing this gap, this study tests the existence and nature of synergies in HRM systems targeted at improving the employees' perception of benevolent and principled ethical climates. Results from a probabilistic sample of 6000 employees from 6 European countries highlight that synergies occur both for benevolent and principled ethical climates, even if the specific components of the HRM system presenting synergistic effects are different in the two cases. Implications of the findings for HRM practice are presented and discussed
    • …
    corecore