420 research outputs found

    Energy Retrofit of a Historic Building Using Simplified Dynamic Energy Modeling

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    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

    Variations in the amount of water ice on Ceres' surface suggest a seasonal water cycle.

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    The dwarf planet Ceres is known to host a considerable amount of water in its interior, and areas of water ice were detected by the Dawn spacecraft on its surface. Moreover, sporadic water and hydroxyl emissions have been observed from space telescopes. We report the detection of water ice in a mid-latitude crater and its unexpected variation with time. The Dawn spectrometer data show a change of water ice signatures over a period of 6 months, which is well modeled as ~2-km2 increase of water ice. The observed increase, coupled with Ceres' orbital parameters, points to an ongoing process that seems correlated with solar flux. The reported variation on Ceres' surface indicates that this body is chemically and physically active at the present time

    HDV can constrain HBV genetic evolution in hbsag: Implications for the identification of innovative pharmacological targets

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    Chronic HBV + HDV infection is associated with greater risk of liver fibrosis, earlier hepatic decompensation, and liver cirrhosis hepatocellular carcinoma compared to HBV mono-infection. However, to-date no direct anti-HDV drugs are available in clinical practice. Here, we identified conserved and variable regions in HBsAg and HDAg domains in HBV + HDV infection, a critical finding for the design of innovative therapeutic agents. The extent of amino-acid variability was measured by Shannon-Entropy (Sn) in HBsAg genotype-D sequences from 31 HBV + HDV infected and 62 HBV mono-infected patients (comparable for demographics and virological-parameters), and in 47 HDAg genotype-1 sequences. Positions with Sn = 0 were defined as conserved. The percentage of conserved HBsAg-positions was significantly higher in HBV + HDV infection than HBV mono-infection (p = 0.001). Results were confirmed after stratification for HBeAg-status and patients’ age. A Sn = 0 at specific positions in the C-terminus HBsAg were correlated with higher HDV-RNA, suggesting that conservation of these positions can preserve HDV-fitness. Conversely, HDAg was characterized by a lower percentage of conserved-residues than HBsAg (p < 0.001), indicating higher functional plasticity. Furthermore, specific HDAg-mutations were significantly correlated with higher HDV-RNA, suggesting a role in conferring HDV replicative-advantage. Among HDAg-domains, only the virus-assembly signal exhibited a high genetic conservation (75% of conserved-residues). In conclusion, HDV can constrain HBsAg genetic evolution to preserve its fitness. The identification of conserved regions in HDAg poses the basis for designing innovative targets against HDV-infection

    Timed rise from floor as a predictor of disease progression in Duchenne muscular dystrophy: An observational study

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    The role of timed items, and more specifically, of the time to rise from the floor, has been reported as an early prognostic factor for disease progression and loss of ambulation. The aim of our study was to investigate the possible effect of the time to rise from the floor test on the changes observed on the 6MWT over 12 months in a cohort of ambulant Duchenne boys.A total of 487 12-month data points were collected from 215 ambulant Duchenne boys. The age ranged between 5.0 and 20.0 years (mean 8.48 ±2.48 DS).The results of the time to rise from the floor at baseline ranged from 1.2 to 29.4 seconds in the boys who could perform the test. 49 patients were unable to perform the test at baseline and 87 at 12 month The 6MWT values ranged from 82 to 567 meters at baseline. 3 patients lost the ability to perform the 6mwt at 12 months. The correlation between time to rise from the floor and 6MWT at baseline was high (r = 0.6, p<0.01).Both time to rise from the floor and baseline 6MWT were relevant for predicting 6MWT changes in the group above the age of 7 years, with no interaction between the two measures, as the impact of time to rise from the floor on 6MWT change was similar in the patients below and above 350 m. Our results suggest that, time to rise from the floor can be considered an additional important prognostic factor of 12 month changes on the 6MWT and, more generally, of disease progression

    Diabete Tipo 1, Tipo 2 e Tipo X

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    Il muro concettuale secondo il quale il diabete in età pediatrica ha preferibilmente una patogenesi autoimmune sta ormai definitivamente crollando. Il diabete in età infantile e adolescenziale è molto più eterogeneo dal punto di vista eziopatogenetico di quanto si pensasse. In presenza di una qualsiasi iperglicemia è ormai diventato importantissimo chiedersi la patogenesi di questo sintomo utilizzando tutti gli strumenti che abbiamo oggi a disposizione

    Nature, formation, and distribution of carbonates on Ceres

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    Different carbonates have been detected on Ceres, and their abundance and spatial distribution have been mapped using a visible and infrared mapping spectrometer (VIR), the Dawn imaging spectrometer. Carbonates are abundant and ubiquitous across the surface, but variations in the strength and position of infrared spectral absorptions indicate variations in the composition and amount of these minerals. Mg-Ca carbonates are detected all over the surface, but localized areas show Na carbonates, such as natrite (Na_2CO_3) and hydrated Na carbonates (for example, Na_2CO_3·H_2O). Their geological settings and accessory NH_4-bearing phases suggest the upwelling, excavation, and exposure of salts formed from Na-CO_3-NH_4-Cl brine solutions at multiple locations across the planet. The presence of the hydrated carbonates indicates that their formation/exposure on Ceres’ surface is geologically recent and dehydration to the anhydrous form (Na_2CO_3) is ongoing, implying a still-evolving body

    A Complex Metabolic Network Confers Immunosuppressive Functions to Myeloid-Derived Suppressor Cells (MDSCs) within the Tumour Microenvironment

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    Myeloid-derived suppressor cells (MDSCs) constitute a plastic and heterogeneous cell population among immune cells within the tumour microenvironment (TME) that support cancer progression and resistance to therapy. During tumour progression, cancer cells modify their metabolism to sustain an increased energy demand to cope with uncontrolled cell proliferation and differentiation. This metabolic reprogramming of cancer establishes competition for nutrients between tumour cells and leukocytes and most importantly, among tumour-infiltrating immune cells. Thus, MDSCs that have emerged as one of the most decisive immune regulators of TME exhibit an increase in glycolysis and fatty acid metabolism and also an upregulation of enzymes that catabolise essential metabolites. This complex metabolic network is not only crucial for MDSC survival and accumulation in the TME but also for enhancing immunosuppressive functions toward immune effectors. In this review, we discuss recent progress in the field of MDSC-associated metabolic pathways that could facilitate therapeutic targeting of these cells during cancer progression
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