2,441 research outputs found
Smart cool mortar for passive cooling of historical and existing buildings: experimental analysis and dynamic simulation
In order to mitigate Urban Heat Island Effect and global warming, both governments and scientific community are working to reduce energy consumptions. In particular, the construction sector has a high potential in reducing energy demand, by means of both active and passive solutions. The European building stock is mainly composed by existing buildings as well as historical ones, which happens to be the less energy efficient ones. Moreover, retrofit operations are more complex on historical buildings, due to strict regulations for the preservation of such historical and cultural heritage. Considering this challenge, in this work we described and in lab analyzed possible passive solutions specifically designed for historical and existing buildings. In particular, we developed innovative cool colored mortars and tested them in lab, as well as investigated cool colored mortars, cool clay tiles and cool natural gravels performance when applied as envelope and roof elements, by means of dynamic simulation
On an innovative approach for microclimate enhancement and retrofit of historic buildings and artworks preservation by means of innovative thin envelope materials
Energy efficiency and environmental sustainability in building has become a key issue since the built environment is nowadays responsible for more than 30% of the total carbon emissions. While new building design and construction reached massive improvements toward net zero energy and high environmental performance standards, existing and historical buildings are still too much energy needy, with a relatively low indoor comfort conditions for both occupants and artworks preserved inside, especially within heritage buildings. Such high architectural value buildings correspond to almost one third of the Italian building stock and they typically need to be re-functionalized for hosting residential, office, or institutional uses, i.e. museums and exhibition areas. In this view, the present research aims at developing a replicable method for assessing and enhancing indoor comfort in historical buildings frequently characterized by too high relative humidity and thermal losses through the envelope. More in details, an innovative envelope material for indoor application, i.e. hygro-adsorbing plaster, has been tested in an ancient Italian castle and its effect has been assessed by means of coupled monitoring and calibrated dynamic simulation. The experimental campaign shows an increase of the Performance Index (PI) in terms of relative humidity acceptable range from 16.1 to 33.3% by applying the new thin plaster. Moreover, the results show that dedicated HVAC systems may support the action of passive strategies for preserving artworks and indoor comfort levels, but at the same time, such passive low-invasive strategies represent a mandatory first step toward energy efficiency, functional, and comfortable cultural heritage architectures.Prof. Luisa F. Cabeza would like to acknowledge the Spanish Government for the funding PRX17/00221 that allowed her to visit University of Perugia during 6 months. Prof. Cabeza would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). GREA is certified agent TECNIO in the category of technology developers from the Government of Catalonia. The corresponding author acknowledgements are due to the ‘CIRIAF program for UNESCO’ in the framework of the UNESCO Chair ‘Water Resources Management and Culture’, for supporting her research. Also, University of Perugia acknowledgements are due to Centro Edile per la Sicurezza e la Formazione–Perugia (in particular to Dr. Cristiana Bartolucci and Dr. Laura Galli), which provided the case study and supported the project COLO ARTE, also financed by Fondazione Cassa di Risparmio di Perugia (“COLO ARTE - COnservazione e vaLOrizzazione degli edifici storici e delle opere d’ARTE” 2016.0276.021)
Thermal comfort in the historical urban canyon: the effect of innovative materials
Urban heat island (UHI) can considerably affect the thermal quality of the urban environment, especially within urban canyons, that have typically low sky view factor and limited surface heat re-emission capability. A huge research effort has been registered to develop mitigation solutions for UHI, such as cool materials and greenery. Nevertheless, it is not always possible to apply such strategies in historical urban environments due to constrains for the preservation of their cultural value that do not allow to modify the exterior architectural appearance of heritage buildings.
In this scenario, the present paper deals with the analysis of the potential of innovative cool materials characterized by the same appearance of historical ones in mitigating the UHI occurring in the context of a historical urban canyon located in central Italy selected as pilot case study. To this purpose, a preliminary experimental characterization of such innovative highly reflective materials has been performed. Afterwards, an experimental continuous monitoring campaign of the main outdoor microclimate parameters and a numerical modelling of the canyon have been carried out to evaluate the local mitigation capability of such materials when applied over the vertical and horizontal surfaces of the historical canyon.
The results show the huge potential of the proposed innovative cool materials in mitigating the local microclimate of the historical urban canyon. In fact, a MOCI reduction up to 0.15 and 0.30 is detected by applying cool red envelope materials and cool red envelope materials plus cool grey paving materials, respectively, on the canyon surfaces
How subjective and non-physical parameters affect occupants’ environmental comfort perception
Employees’ wellbeing and comfort perception demonstrated to largely influence their productivity and tolerability of slight thermal discomfort conditions in the working spaces. Their whole comfort perception indeed depends on several parameters related to physical boundary conditions but also to the adaptation capability of occupants themselves and other personal, difficult to measure, variables. According to the available standards and regulations, only physical and measurable environmental parameters must be considered to evaluate occupants’ comfort conditions. Therefore, non-measurable factors such as socio-psychological, physiological, medical ones are currently not systematically considered. The present work aims to identify possible benefits in terms of occupants’ comfort perception due to non-physical strategies aimed at improving the work-environment quality and livability. To this aim, the environmental multi-physics and multi-domain performance of a mixed industry-office building is investigated through coupled in-field microclimate monitoring and questionnaires campaigns. The experimental microclimate monitoring and survey campaign were carried out to understand (i) the realistic indoor environmental conditions in terms of physical and measurable parameters and (ii) the personal perceptions and attitudes of the occupants with respect to those same ambient parameters, including also acoustic, lighting and medical investigation. Moreover, the collected experimental data were used to determine occupants’ comfort level through the classic comfort models, to be compared to the identified role of non-physical parameters on occupants’ final perception about the indoor environment. The main results show that non-measurable factors induced by virtuous company policy to improve employees’ working environment are effectively able to positively influence their whole-comfort perception even if the majority of workers do not have the opportunity to control their working environment. In fact, the consolidated comfort theories underestimate people satisfaction, as demonstrated by more than the 80% employees, who declared to be positively influenced by the pleasant aesthetics and livability of the workplace. The year-round experimental campaign demonstrated the need to further investigate the key role of non-physical parameters for possible incorporation into whole-comfort prediction models and standards. The role of such strategies could therefore be realistically considered as energy saving opportunities since they make building occupants much more open to tolerate slight uncomfortable conditions
Relevamiento y análisis previos a la instalación de un sistema piloto fotovoltaico conectado a red en el Poder Judicial de Salta como aporte al uso racional de energía y a la promoción de la energía solar
Se relatan las mediciones y relevamientos preliminares a la instalación de un SFVCR - en el marco del Proyecto IRESUD - en la Escuela de la Magistratura del Poder Judicial de Salta que pretende contribuir a la producción distribuida de energía limpia. La innovación es acompañada por un proceso de relevamiento del consumo de energía y de los hábitos de uso por parte de los agentes que diariamente desarrollan su tarea en ese edificio público mediante la aplicación de una encuesta. La caracterización del consumo de energía eléctrica estimado muestra unos 2,6kW destinados a iluminación, 10,15kW a alimentar equipos de oficina (incluyendo equipos de informática) y 40,80kW a climatización. Se realiza una caracterización preliminar de dos de los módulos fotovoltaicos y se estima la energía a ser producida anualmente. Se analiza la inclinación de los paneles a ser ubicados en la fachada Norte y se discute el aporte que el SFVCR hace al consumo de electricidad de la EM. Se detectan problemas en el uso de la energía eléctrica destinada a la climatización de las oficinas del ala Este debido a la incidencia de radiación solar directa y a un uso inadecuado de las aberturas mientras funcionan equipos de aire acondicionado. Se proponen algunas medidas de uso racional de la energía y se discute su integración con el novedoso sistema de co-generación para contribuir, desde dos vertientes- la generación de electricidad a partir de la energía solar en el punto de consumo - y el uso racional de la energía a una mejora en el abastecimiento eléctrico urbano.Fil: Javi, Veronica Mercedes. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Salta. Instituto de Invest.en Energia No Convencional; ArgentinaFil: Franco, Ada Judith. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Salta. Instituto de Investigaciones en Energía No Convencional; ArgentinaFil: Montero Larocca, María Teresa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Salta. Instituto de Investigaciones en Energía No Convencional; ArgentinaFil: Serrano, Víctor Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cietífico Tecnológico - CONICET -Salta. Instituto de Investigaciones en Energía No Convencional; Argentin
Drosophila CG3303 is an essential endoribonuclease linked to TDP-43-mediated neurodegeneration
Endoribonucleases participate in almost every step of eukaryotic RNA metabolism, acting either as degradative or biosynthetic enzymes. We previously identified the founding member of the Eukaryotic EndoU ribonuclease family, whose components display unique biochemical features and are flexibly involved in important biological processes, such as ribosome biogenesis, tumorigenesis and viral replication. Here we report the discovery of the CG3303 gene product, which we named DendoU, as a novel family member in Drosophila. Functional characterisation revealed that DendoU is essential for Drosophila viability and nervous system activity. Pan-neuronal silencing of dendoU resulted in fly immature phenotypes, highly reduced lifespan and dramatic motor performance defects. Neuron-subtype selective silencing showed that DendoU is particularly important in cholinergic circuits. At the molecular level, we unveiled that DendoU is a positive regulator of the neurodegeneration-associated protein dTDP-43, whose downregulation recapitulates the ensemble of dendoU-dependent phenotypes. This interdisciplinary work, which comprehends in silico, in vitro and in vivo studies, unveils a relevant role for DendoU in Drosophila nervous system physio-pathology and highlights that DendoU-mediated neurotoxicity is, at least in part, contributed by dTDP-43 loss-of-function
Detection of Microbial Translocation in HIV and SIV Infection Using the Limulus Amebocyte Lysate Assay is Masked by Serum and Plasma
Objective: Microbial translocation (MT) is thought to be a major contributor to the pathogenesis of HIV-related immune activation, and circulating lipopolysaccharide (LPS) from Gram-negative bacteria is the principle measurement of this process. However, related research has been impeded by inconsistent LPS test results. Methods: Specimens were obtained from HIV-infected adults enrolled in the PEARLS study (ACTG A5175) and HIV-HCV co-infected participants enrolled in a study of liver disease staging using MRI elastography. Pig-tailed macaque specimens were obtained from SIV-infected and –uninfected animals. Samples were tested for LPS using the LAL assay with diazo-coupling modifications to improve sensitive detection. Results: When exogenous LPS was added to macaque plasma, >25% inhibition of LPS detection was found in 10/10 (100%) samples at 20% plasma concentration compared to control; in contrast 5/10 (50%) samples at 2% plasma concentration (p = 0.07) and 0/10 (0%) at 0.1% plasma concentration (p = 0.004) showed >25% inhibition of LPS detection. Similarly, when LPS was added to human serum, >25% inhibition of LPS detection was found in 5/12 (42%) of samples at 2% serum concentration compared to control, while 0/12 (0%) of samples in 0.1% serum showed >25% inhibition of LPS detection (p = 0.07). Likewise, LPS detection in human sera without exogenous LPS was improved by dilution: LPS was detected in 2/12 (17%) human samples in 2% serum, ranging from 3,436–4,736 pg/mL, compared to 9/12 (75%) samples in 0.1% serum, ranging from 123 pg/mL –60,131 pg/mL (p = 0.016). In a separate validation cohort of HIV-HCV co-infected participants sampled at two different times on the same day, LPS measured in 0.2% plasma and with diazo-coupling was closely correlated between the first and second samples (R = 0.66, p<0.05). Conclusions: Undiluted serum and plasma mask LPS detection. The extent of MT may be substantially underestimated
Sustainable New Brick and Thermo-Acoustic Insulation Panel from Mineralization of Stranded Driftwood Residues
There is considerable interest recently in by-products for application in green buildings.
These materials are widely used as building envelope insulators or blocks. In this study, an
experimental study was conducted to test stranded driftwood residues as raw material for possible
thermo-acoustic insulation panel and environmentally sustainable brick. The thermal and acoustic
characteristics of such a natural by-product were examined. Part of samples were mineralized by
means of cement-based additive to reinforce the material and enhance its durability as well as fire
resistance. Several mixtures with different sizes of ground wood chips and different quantities of
cement were investigated. The thermo-acoustic in-lab characterization was aimed at investigating
the thermal conductivity, thermal diffusivity, volumetric specific heat, and acoustic transmission loss.
All samples were tested before and after mineralization. Results from this study indicate that it is
possible to use stranded driftwood residues as building materials with competitive thermo-acoustic
properties. In fact, the thermal conductivity was shown to be always around 0.07 W/mK in the
unbound samples, and around double that value for the mineralized samples, which present a much
higher volumetric specific heat (1.6 MJ/m3K) and transmission loss capability. The lignin powder
showed a sort of intermediate behavior between the unbound and the mineralized samples.The authors would like to thank Gabriele Franceschetti and CVR s.r.l. for assisting the mineralization procedure of the samples. Anna Laura Pisello’s acknowledgments are due to the “CIRIAF program for UNESCO” in the framework of the UNESCO Chair “Water Resources Management and Culture”, for supporting her research. The research was founded by the Italian Environmental Ministry with an agreement entitled “Recovery and energy valorization of stranded driftwood residues” in 2014–2016. The research team leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 657466 (INPATH–TES) and No. 678407 (ZERO-PLUS)
Road traffic pollution and childhood leukemia: a nationwide case-control study in Italy
Background The association of childhood leukemia with traffic pollution was considered in a number of studies from 1989 onwards, with results not entirely consistent and little information regarding subtypes. Aim of the study We used the data of the Italian SETIL case-control on childhood leukemia to explore the risk by leukemia subtypes associated to exposure to vehicular traffic. Methods We included in the analyses 648 cases of childhood leukemia (565 Acute lymphoblastic–ALL and 80 Acute non lymphoblastic-AnLL) and 980 controls. Information on traffic exposure was collected from questionnaire interviews and from the geocoding of house addresses, for all periods of life of the children. Results We observed an increase in risk for AnLL, and at a lower extent for ALL, with indicators of exposure to traffic pollutants. In particular, the risk was associated to the report of closeness of the house to traffic lights and to the passage of trucks (OR: 1.76; 95% CI 1.03–3.01 for ALL and 6.35; 95% CI 2.59–15.6 for AnLL). The association was shown also in the analyses limited to AML and in the stratified analyses and in respect to the house in different period of life. Conclusions Results from the SETIL study provide some support to the association of traffic related exposure and risk for AnLL, but at a lesser extent for ALL. Our conclusion highlights the need for leukemia type specific analyses in future studies. Results support the need of controlling exposure from traffic pollution, even if knowledge is not complete
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