229 research outputs found

    The Effect of Water Spray Systems on Thermal and Solar Performance of an ETFE Panel for Building Envelope

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    ETFE membranes are generally used in architecture for large roofing and fa√ßade systems, because of their transparency and lightness compared to glass alternatives. Multilayer ETFE panels are used to improve single membrane systems performances, reducing thermal losses, by the use of an air gap between two or more ETFE foils, generally serigraphed or surface treated to reduce solar gains. Surface temperatures and global solar radiation strongly affects mean radiant temperature (MRT), and comfort perceived by a user facing a transparent envelope as well as solar gains strongly influences primary energy use for cooling in summer conditions. In the following paper an alternative dynamic solar gains mitigation strategy is presented and applied to a double layer, non-cushions, ETFE panel for fa√ßades. We measured the effectiveness of a water spray system located in the air-gap between the parallel ETFE foils and used to reduce surface temperatures and solar access depending on different summer solar radiation values and outdoor/indoor air temperature conditions. Systems alternative with different in nozzle dimension, water spray geometry and water consumption were already tested to evaluate the best compromise between solar gains reduction and water use. The results are preliminary but we noticed that a reduction up to the 10% of the total solar gains could be achieved as well as a reduction of 10 ¬įC of surface temperature. Comfort evaluation for a standard indoor space were already done

    Structural analysis of the double-walled copper-steel cryogenic chamber of the ASTAROTH experiment

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    This document describes the verification process of structural performance of the double- walled copper-steel cryogenic chamber of the ASTAROTH (All Sensitive crysTal ARray with lOw THreshold) experiment and the evaluation of the stresses generated near the thermal bridge connecting the inner and outer wall. The chamber consists of an external AISI 316L stainless steel dewar and an inner double-walled OF (Oxygen Free) copper dewar connected to an AISI 316L stainless steel flanged collar. The results showed that close to the thermal bridge (copper-steel junction) the stresses slightly exceed the YS of copper at the estimated operating temperature (localised strain-hardening condition). On the other hand, the safety coefficient respect to fracture is well above one for both materials. This condition, together with the fact that limited cooling cycles are expected during the operating life of the system, leads to the assumption that a progressive material hardening will occur in this area, thus locally raising the YS limit

    Experimental Assessment of the Reflection of Solar Radiation from Façades of Tall Buildings to the Pedestrian Level

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    Urban climates are highly influenced by the ability of built surfaces to reflect solar radiation, and the use of high-albedo materials has been widely investigated as an effective option to mitigate urban overheating. While diffusely solar reflective walls have attracted concerns in the architectural and thermal comfort community, the potential of concave and polished surfaces, such as glass and metal panels, to cause extreme glare and localized thermal stress has been underinvestigated. Furthermore, there is the need for a systematic comparison of the solar concentration at the pedestrian level in front of tall buildings. Herein, we show the findings of an experimental campaign measuring the magnitude of the sunlight reflected by scale models reproducing archetypical tall buildings. Three 1:100 scaled prototypes with different shapes (classic vertical façade, 10% tilted façade, curved concave façade) and different finishing materials (representative of extremes in reflectance properties of building materials) were assessed. A specular surface was assumed as representative of a glazed façade under high-incidence solar angles, while selected light-diffusing materials were considered sufficient proxies for plaster finishing. With a diffusely reflective façade, the incident radiation at the pedestrian level in front of the building did not increase by more than 30% for any geometry. However, with a specular reflective (i.e., mirror-like) flat façade, the incident radiation at the pedestrian level increased by more than 100% and even by more than 300% with curved solar-concentrating geometries. In addition, a tool for the preliminary evaluation of the solar reflectance risk potential of a generic complex building shape is developed and presented. Our findings demonstrate that the solar concentration risk due to mirror-like surfaces in the built environment should be a primary concern in design and urban microclimatology

    Sheep brain atlas creation. Diffusion tensor imaging and Scanning electron microscope in sheep brain analysis

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    IntroductionsAim of EDEN 2020 project is the development of a steerable catheter for CED system in glioblastoma therapy. The VET group is involved in realization and validation of the proper animal model.For surgical planning purpose a Diffusion Tensor Imaging (DTI) of white matter tracts in the sheep is necessary to identify the target points useful for the catheter introduction.The analysis of the sheep brain under a Scanning Electron Microscope (SEM) is required to understand any alterations due to the catheter introduction and to fluids injection during CED administration. Materials and methodsAnimals were treated in accordance with the European Communities Council directive (86/609/EEC), to the laws and regulations on animal welfare enclosed in D.L.G.S. 26/2014A total of five 70 kg female, one year old, sheep were used for the study.All animals, under general anesthesia, underwent to Magnetic Resonance Imaging (MRI) acquisition. MRI scanner used was Philips Ingenia 1.5 Tesla system.Once the DTI imaging were acquired the animals were euthanased, sheep brain was collected and samples of white matter tracts obtained with disposable biopsy punches of 1.5-2 mm of diameter.The samples were fixed, stained in Osmium tetroxide (OsO4) and then embedded with two different protocols (cold curing vs thermal curing) in resin for the Focused Ion Beam (FIB) SEM analyses. Results and discussionAll the DTI images were uploaded to TrackVis software and major white matter fiber tracts analysed. Corticospinal tract, visual radiation, fornix and fronto-occipital fasciculus were identified.Corticospinal tract was identified as major white matter tract in sheep brain and useful as target area for the research aims.For the SEM analysis the thermal protocol was recognised as better curing methods for the research purpose than cold curing one. ConclusionThe data acquired in this study are still submitted to analysis. AcknowledgmentThe project has received funding from the European Union’s EU Research and Innovation programme Horizon 2020 (no 688279)

    Diagnostic Workup of Neonates With Esophageal Atresia : Results From the EUPSA Esophageal Atresia Registry

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    Aim:Controversies exist on the optimal diagnostic workup for neonates with esophageal atresia (EA) with/without tracheoesophageal fistula (TEF). Aim of this study was to describe the current diagnostic policies in EA/TEF patients enrolled in an International multicenter registry. Methods:All patients consecutively registered from July 2014 to December 2017 in the EUPSA Esophageal Atresia Registry (EUPSA-EAR) were included in the study. Data related to diagnostic investigations among Centers forming the EUPSA-EAR were analyzed. Main Results:During the study period, 374 consecutive patients were recorded by 23 Centers. The majority of patients underwent chest X-rays, echocardiography, abdominal ultrasound, and abdominal X-rays. Preoperative bronchoscopy and esophageal gap measurement were performed in one third of the patients. Conclusions:Present data from a large cohort of patients from the EUPSA-EAR show both inter-institutional and intra-institutional variability in diagnostic workup of patients with EA/TEF. Efforts should be made to develop guidelines on the diagnostic workup for EA/TEF patients.Peer reviewe

    Computational Design and Parametric Optimization Approach with Genetic Algorithms of an Innovative Concrete Shading Device System

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    Office buildings in contemporary architecture usually have a high value of window to wall ratio (WWR) determining transparent façade as the most important part of the building façade to control solar gains, thermal losses and visual comfort. Therefore, in order to fulfill strict National energy regulations and LEED requirements, façades require a proper balance between transparent and opaque or shaded surfaces to avoid overheating, optimizing daylighting aspects and outdoor perception. Concrete is usually used in building sector for primary structure or secondary structure of cladding solutions. With new concrete materials and innovative digital fabrication process is possible to rediscover concrete for high performance façade/shading solutions. The aim of this paper is the development of high performance concrete static shading system using computational design approach and its optimization, by genetic algorithms, based on several parameters such as radiation control, outdoor view and daylight indexes and energy performance. After the development of a geometry definition managed with a parametric modelling approach (Rhinoceros and Grasshopper), genetic algorithm optimization were used in order to define the openness's sizes and their cutting angle to minimize solar radiation entrance during year, maintaining outdoor view. The possible geometric alternatives were part of a sensitivity analysis with Radiance and Energy-plus engine to assess the shading system performance in terms of daylighting and energy use. In order to evaluate their performances a study case, a single office unit placed in Milan (Italy) was defined, considered with wall facing outdoors, having a WWR of 86%, and five surfaces adiabatic. The results shows that using this approach is possible to develop an effectiveness shading solution able to control radiation over the year and likewise guarantee a high performance regarding the outdoor perception and visual comfort

    ERP signs of categorical and supra-categorical processing of visual information

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    Background: The aim of the present study was to investigate to what extent shared and distinct brain mechanisms are possibly subserving the processing of visual supra-categorical and categorical knowledge as observed with event-related potentials of the brain. Access time to these knowledge types was also investigated. Picture pairs of animals, objects, and mixed types were presented. Participants were asked to decide whether each pair contained pictures belonging to the same category (either animals or man-made objects) or to different categories by pressing one of two buttons. Response accuracy and reaction times (RTs) were also recorded. Results: Both ERPs and RTs were grand-averaged separately for the same-different supra-categories and the animal-object categories. Behavioral performance was faster for more endomorphic pairs, i. e., animals vs. objects and same vs. different category pairs. For ERPs, a modulation of the earliest C1 and subsequent P1 responses to the same vs. different supra-category pairs, but not to the animal vs. object category pairs, was found. This finding supports the view that early afferent processing in the striate cortex can be boosted as a by-product of attention allocated to the processing of shapes and basic features that are mismatched, but not to their semantic quintessence, during same-different supra-categorical judgment. Most importantly, the fact that this processing accrual occurred independent of a traditional experimental condition requiring selective attention to a stimulus source out of the various sources addressed makes it conceivable that this processing accrual may arise from the attentional demand deriving from the alternate focusing of visual attention within and across stimulus categorical pairs' basic structural features. Additional posterior ERP reflections of the brain more prominently processing animal category and same-category pairs were observed at the N1 and N2 levels, respectively, as well as at a late positive complex level, overall most likely related to different stages of analysis of the greater endomorphy of these shape groups. Conversely, an enhanced fronto-central and fronto-lateral N2 as well as a centro-parietal N400 to man-made objects and different-category pairs were found, possibly indexing processing of these entities' lower endomorphy and isomorphy at the basic features and semantic levels, respectively. Conclusion: Overall, the present ERP results revealed shared and distinct mechanisms of access to supra-categorical and categorical knowledge in the same way in which shared and distinct neural representations underlie the processing of diverse semantic categories. Additionally, they outlined the serial nature of categorical and supra-categorical representations, indicating the sequential steps of access to these separate knowledge types. (C) 2014 Elsevier B.V. All rights reserved

    Desiccation of potato haulm with contact herbicides and the final quality of tubers

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    Desiccation of potato (Solanum tuberosum L.) haulms makes it possible to establish a physiological homogeneity of the haulms and anticipate the harvest of the tubers. This study aimed to evaluate the efficiency of different herbicides in the desiccation of potato haulms applied at the maturation phenological stages, and the effect of these treatments on the quality of tubers. An experiment was conducted in the field, in an area planted with Orchestra potatoes. This was a completely randomized experimental design with four repetitions. At the maturation phenological stages, the crop was applied with herbicides: diquat dibromide (400 g ha-1), paraquat dichloride (400 g ha-1), saflufenacil (70 g ha-1) and carfentrazone ethyl (60 g ha-1). Visual phytotoxicity assessments were performed at 3, 5, 10 and 15 days after application of treatments (DAT). At 15 DAT, tubers were harvested and evaluated for Brix (%), individual weight (g); diameter (cm); texture (kg/cm2) and starch. At 15 DAT, all herbicides resulted in desiccation close to 100%, however, saflufenacil showed the lowest speed of desiccation, since at 5 DAT the phytotoxicity was less than 86.25%. Texture, brix and diameter showed no statistical difference. The control and saflufenacil resulted in the lowest concentration of starch in the tubers and the highest concentration was obtained for carfentrazone-ethyl, paraquat and diquat. The treatments carfentrazone-ethyl, diquat dibromide and paraquat dichloride, were the most suitable for desiccation of potato haulms, providing fast desiccation speed and greater accumulation of starch in the tubers.A desseca√ß√£o das ramas de batata (Solanum tuberosum L.) possibilita estabelecer uma homogeneidade fisiol√≥gica das ramas e antecipa√ß√£o da colheita dos tub√©rculos. O objetivo deste trabalho foi avaliar a efici√™ncia de diferentes herbicidas na desseca√ß√£o das ramas de batata aplicados no est√°dio fenol√≥gico de matura√ß√£o, e o efeito desses tratamentos sobre a qualidade dos tub√©rculos. Foi realizado um experimento em campo, em √°rea cultivada com batata da variedade Orchestra. O delineamento experimental foi inteiramente casualizado com quatro repeti√ß√Ķes. No est√°dio fenol√≥gico de matura√ß√£o, foram aplicados os herbicidas: dibrometo de diquate (400 g ha-1), dicloreto de paraquate (400 g ha-1), saflufenacil (70 g ha-1) e carfentrazona-et√≠lica (60 g ha-1). Avalia√ß√Ķes visuais de fitotoxicidade foram realizadas aos 3, 5, 10 e 15 dias ap√≥s a aplica√ß√£o dos tratamentos (DAT). Aos 15 DAT foi realizada a colheita, e avalia√ß√Ķes de brix (%), peso individual do tub√©rculo (g); di√Ęmetro (cm); textura (kg/cm2) e amido dos tub√©rculos. Aos 15 DAT todos os herbicidas resultaram em desseca√ß√£o pr√≥xima a 100%, no entanto, o saflufenacil apresentou a menor velocidade de desseca√ß√£o, pois aos 5 DAT a fitotoxicidade foi inferior a 86,25%. As vari√°veis textura, brix e di√Ęmetro n√£o apresentaram diferen√ßa estat√≠stica. A testemunha e o saflufenacil, resultaram na menor concentra√ß√£o de amido nos tub√©rculos e a maior concentra√ß√£o foi obtida para carfentrazona-et√≠lica, paraquat e diquat. Os tratamentos carfentrazona-et√≠lica, dibrometo de diquate e dicloreto de paraquate, foram os mais adequados para desseca√ß√£o das ramas de batata, proporcionando r√°pida velocidade de desseca√ß√£o e maior ac√ļmulo de amido nos tub√©rculos

    SGSI project at CNAF

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    The Italian Tier1 center is mainly focused on LHC and physics experiments in general. Recently we tried to widen our area of activity and established a collaboration with the University of Bologna to set-up an area inside our computing center for hosting experiments with high demands of security and privacy requirements on stored data. The first experiment we are going to host is Harmony, a project part of IMI's Big Data for Better Outcomes programme (IMI stands for Innovative Medicines Initiative). In order to be able to accept this kind of data we had to make a subset of our computing center compliant with the ISO 27001 regulation. In this article we will describe the SGSI project (Sistema Gestione Sicurezza Informazioni, Information Security Management System) with details of all the processes we have been through in order to become ISO 27001 compliant, with a particular focus on the separation of the project dedicated resources from all the others hosted in the center. We will also describe the software solutions adopted to allow this project to accept in the future any experiment or collaboration in need for this kind of security procedures

    Lung Ultrasound in COVID-19 Pneumonia: Correlations with Chest CT on Hospital admission

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    Background: Lung ultrasound (LUS) is an accurate, safe, and cheap tool assisting in the diagnosis of several acute respiratory diseases. The diagnostic value of LUS in the workup of coronavirus disease-19 (COVID-19) in the hospital setting is still uncertain. Objectives: The aim of this observational study was to explore correlations of the LUS appearance of COVID-19-related pneumonia with CT findings. Methods: Twenty-six patients (14 males, age 64 ¬Ī 16 years) urgently hospitalized for COVID-19 pneumonia, who underwent chest CT and bedside LUS on the day of admission, were enrolled in this observational study. CT images were reviewed by expert chest radiologists, who calculated a visual CT score based on extension and distribution of ground-glass opacities and consolidations. LUS was performed by clinicians with certified competency in thoracic ultrasonography, blind to CT findings, following a systematic approach recommended by ultrasound guidelines. LUS score was calculated according to presence, distribution, and severity of abnormalities. Results: All participants had CT findings suggestive of bilateral COVID-19 pneumonia, with an average visual scoring of 43 ¬Ī 24%. LUS identified 4 different possible -abnormalities, with bilateral distribution (average LUS score 15 ¬Ī 5): focal areas of nonconfluent B lines, diffuse confluent B lines, small subpleural microconsolidations with pleural line irregularities, and large parenchymal consolidations with air bronchograms. LUS score was significantly correlated with CT visual scoring (r = 0.65, p < 0.001) and oxygen saturation in room air (r = -0.66, p < 0.001). Conclusion: When integrated with clinical data, LUS could represent a valid diagnostic aid in patients with suspect COVID-19 pneumonia, which reflects CT findings
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