101 research outputs found

    Rome Community Ring - Un progetto per il forte Portuense

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    L’idea di tesi nasce sulla base di un bando di concorso pubblicato su Young Architects Competition, che prevede il recupero e la ri-funzionalizzazione del Forte Portuense a Roma e la realizzazione di strutture di servizio quali un asilo, un centro anziani, un centro sportivo e sedi di associazioni di quartieri attualmente esistenti ma collocate all'interno di costruzioni prive di valenza storica estetico-architettonica. Il Forte Portuense è uno dei 15 forti militari del campo trincerato che circonda Roma costituito da un anello di circa 40 km che fu realizzato a partire dal 1877 per la difesa della capitale. Nessuna di queste strutture è mai stata utilizzata a scopi bellici e l’espansione urbana le ha completamente inglobate nella città da un punto di vista territoriale ma non funzionale. La sfida proposta dal concorso è proprio quella di restituire questo grande spazio alla città ed in particolar modo agli abitanti del quartiere realizzando un luogo di attività culturali che risponda alle necessità dei cittadini senza dimenticarne la potenziale attrattività turistica in quanto manufatto storico. Per motivi di strategia militare questi forti sono stati costruiti seguendo il più possibile l’andamento del terreno, con ampi terrapieni a ricoprire ambienti quasi totalmente ipogei; è chiaro quindi che la relazione con la morfologia dell’ambiente circostante è strettissima, e rende indispensabile una progettazione paesaggistica oltre a quella architettonica delle singole opere richieste. Lo scopo della tesi è dunque quello di coinvolgere ed unificare in un unico processo progettazione paesaggistica ed architettonica allo scopo di realizzare un progetto che risponda al programma del concorso, studiando le diverse opzioni di approccio di fronte ad architetture storiche (problema largamente diffuso in Italia) e come queste possono essere efficacemente coinvolte nella realizzazione di nuovi spazi che superando la mera riqualificazione del manufatto stesso valorizzino significativamente gli ambiti urbani in cui sono immerse

    P-wave Variability and Atrial Fibrillation

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    The analysis of P-wave template has been widely used to extract indices of Atrial Fibrillation (AF) risk stratification. The aim of this paper was to assess the potential of the analysis of the P-wave variability over time in patients suffering from atrial fibrillation. P-wave features extracted from P-wave template together with novel indices of P-wave variability have been estimated in a population of patients suffering from persistent AF and compared to those extracted from control subjects. We quantify the P-wave variability over time using three algorithms and we extracted three novel indices: one based on the cross-correlation coefficients among the P-waves (Cross-Correlation Index, CCI), one associated to variation in amplitude of the P-waves (Amplitude Dispersion Index, ADI), one sensible to the phase shift among P-waves (Warping Index, WI). The control group resulted to be characterized by shorter P-wave duration and by a less amount of fragmentation and variability, respect to AF patients. The parameter CCI shows the highest sensitivity (97.3%) and a good specificity (95%)

    Brain-heart pathways to blood pressure-related hypoalgesia

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    OBJECTIVE: High blood pressure (BP) is associated with reduced pain sensitivity, known as BP-related hypoalgesia. The underlying neural mechanisms remain uncertain, yet arterial baroreceptor signaling, occurring at cardiac systole, is implicated. We examined normotensives using functional neuroimaging (fMRI) and pain stimulation during distinct phases of the cardiac cycle to test the hypothesized neural mediation of baroreceptor-induced attenuation of pain. METHODS: Eighteen participants (10 women; 32.7 ± 6.5 years) underwent BP monitoring over one week at home, and individual pain thresholds were determined in the lab. Subsequently, participants were administered unpredictable painful and non-painful electrocutaneous shocks (stimulus type), timed to occur either at systole or diastole (cardiac phase) in an event-related design. After each trial, participants evaluated their subjective experience. RESULTS: Subjective pain was lower for painful stimuli administered at systole compared to diastole, F1, 2283 = 4.82; p = 0.03. Individuals with higher baseline BP demonstrated overall lower pain perception, F1, 2164 = 10.47; p < 0.0001. Within the brain, painful stimulation activated somatosensory areas, prefrontal cortex, cingulate cortex, posterior insula, amygdala, and the thalamus. Stimuli delivered during systole (concurrent with baroreceptor discharge) activated areas associated with heightened parasympathetic drive. No stimulus type x cardiac phase interaction emerged except for a small cluster located in the right parietal cortex. CONCLUSIONS: We confirm the negative associations between BP and pain, highlighting the antinociceptive impact of baroreceptor discharge. Neural substrates associated with baroreceptor/BP-related hypoalgesia include superior parietal lobule, precentral and lingual gyrus, regions typically involved in the cognitive aspects of pain experience

    Complexity of MRI induced heating on metallic leads: Experimental measurements of 374 configurations

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    <p>Abstract</p> <p>Background</p> <p>MRI induced heating on PM leads is a very complex issue. The widely varying results described in literature suggest that there are many factors that influence the degree of heating and that not always are adequately addressed by existing testing methods.</p> <p>Methods</p> <p>We present a wide database of experimental measurements of the heating of metallic wires and PM leads in a 1.5 T RF coil. The aim of these measurements is to systematically quantify the contribution of some potential factors involved in the MRI induced heating: the length and the geometric structure of the lead; the implant location within the body and the lead path; the shape of the phantom used to simulate the human trunk and its relative position inside the RF coil.</p> <p>Results</p> <p>We found that the several factors are the primary influence on heating at the tip. Closer locations of the leads to the edge of the phantom and to the edge of the coil produce maximum heating. The lead length is the other crucial factor, whereas the implant area does not seem to have a major role in the induced temperature increase. Also the lead structure and the geometry of the phantom revealed to be elements that can significantly modify the amount of heating.</p> <p>Conclusion</p> <p>Our findings highlight the factors that have significant effects on MRI induced heating of implanted wires and leads. These factors must be taken into account by those who plan to study or model MRI heating of implants. Also our data should help those who wish to develop guidelines for defining safe medical implants for MRI patients. In addition, our database of the entire set of measurements can help those who wish to validate their numerical models of implants that may be exposed to MRI systems.</p

    LIFE+IPNOA mobile prototype for the monitoring of soil N2O emissions from arable crops: First-year results on durum wheat

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    Agricultural activities are co-responsible for the emission of the most important greenhouse gases: carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Development of methodologies to improve monitoring techniques for N2O are still needful. The LIFE+IPNOA project aims to improve the emissions monitoring of nitrous oxide from agricultural soils and to identify the agricultural practices that can limit N2O production. In order to achieve this objective, both a mobile and a stationary instrument were developed and validated. Several experimental field trials were set up in two different sites investigating the most representative crops of Tuscany (CentralItaly), namely durum wheat, maize, sunflower, tomato and faba bean. The field trials were realized in order to test the effect on N2O emissions of key factors: tillage intensity, nitrogen fertiliser rate and irrigation. The field trial on durum wheat was set up in 2013 to test the effect of tillage intensity (minimum and conventional tillage) and nitrogen fertilisation rate (0, 110, 170 kg N ha–1) on soil N2O flux. Monitoring was carried out using the IPNOA mobile prototype. Preliminary results on N2O emissions for the durum wheat growing season showed that mean daily N2O fluxes ranged from –0.13 to 6.43 mg m–2 day–1 and cumulative N2O-N emissions over the period ranged from 827 to 2340 g N2O-N ha–1. Tillage did not affect N2O flux while increasing nitrogen fertilisation rate resulted to significantly increase N2O emissions. The IPNOA mobile prototype performed well during this first year of monitoring, allowing to catch both very low fluxes and peaks on N2O emissions after nitrogen supply, showing a good suitability to the field conditions

    Electromagnetic fields counteract IL-1β during chondrogenesis in synovial bovine mesenchymal progenitor cells

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    Objective. Mesenchymal stem cells (MSCs) isolated from synovium and from synovial fluid, have shown a chondrogenesis potential suggesting that synovium is an excellent source of MSCs for cartilage regeneration. Electromagnetic fields (EMFs) display several effects on cartilage: increase the synthesis of proteoglycans (PGs), prevents the catabolic effect of the pro-inflammatory cytokine interleukin-1β (IL-1β), appear useful for the treatment of osteoarthritis. Our goal was to evaluate if the chondrogenic differentiation of synovial bovine mesenchymal progenitor cells, may be influenced by EMFs. Further, as chondrogenic differentiation of MSCs could be altered in an inflammatory environment and EMFs can counteract IL-1β activity, we also evaluated the role of EMFs during chondrogenic differentiation in the presence of IL-1β. Design. Synovial fluid was aspirated from the metacarpophalangeal joints of bovine. Synovial cells at the 3rd passage were centrifuged to obtain pellet cultures. Pellets were cultured in chondrogenic medium alone (control) or supplemented with 10 ng/ml TGF-β3 and/or 50 ng/ml IL-1β. The pellets were unexposed or exposed to EMF (75 Hz, 1.5 mT) (Igea, Carpi, Italy), during the whole period in culture (34 days). Alcian blue for sulphated glycosaminoglycans and immunostaining for type II collagen, were performed. PG synthesis was measured by radioactive 35S-sulphate incorporation. Results. Pellets cultured in the presence of TGF-β3 exhibited positive staining for type II collagen and Alcian blue, compared to control, indicating chondrogenic differentiation of synovial bovine mesenchymal progenitor cells. In the presence of IL-1β, type II collagen and Alcian blue staining dramatically decreased compared to TGF-β3 treatment alone. When pellets treated with both TGF-β3 and IL-1β were exposed to EMF, the histochemical staining for type II collagen and Alcian blue increased compared to EMF-unexposed pellets, suggesting that EMF might counteract the IL-1β effect. Biochemical analysis on PG synthesis confirmed histochemical data. Conclusions. The presence of inflammatory cytokines, such as IL-1β in human joints, may explain why existing methods of cartilage engineering repair strategies, that rely on the in situ differentiation of MSCs, fail to provide a reliably successful. Results of this study support the hypothesis that EMF treatment may favour chondrogenic differentiation in inflammatory conditions, suggesting a possible strategy for improving the clinical outcome of cartilage repair procedures

    Acidic microenvironment plays a key role in human melanoma progression through a sustained exosome mediated transfer of clinically relevant metastatic molecules

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    Background: Microenvironment cues involved in melanoma progression are largely unknown. Melanoma is highly influenced in its aggressive phenotype by the changes it determinates in its microenvironment, such as pH decrease, in turn influencing cancer cell invasiveness, progression and tissue remodelling through an abundant secretion of exosomes, dictating cancer strategy to the whole host. A role of exosomes in driving melanoma progression under microenvironmental acidity was never described. Methods: We studied four differently staged human melanoma lines, reflecting melanoma progression, under microenvironmental acidic pHs pressure ranging between pH 6.0-6.7. To estimate exosome secretion as a function of tumor stage and environmental pH, we applied a technique to generate native fluorescent exosomes characterized by vesicles integrity, size, density, markers expression, and quantifiable by direct FACS analysis. Functional roles of exosomes were tested in migration and invasion tests. Then we performed a comparative proteomic analysis of acid versus control exosomes to elucidate a specific signature involved in melanoma progression. Results: We found that metastatic melanoma secretes a higher exosome amount than primary melanoma, and that acidic pH increases exosome secretion when melanoma is in an intermediate stage, i.e. metastatic non-invasive. We were thus able to show that acidic pH influences the intercellular cross-talk mediated by exosomes. In fact when exposed to exosomes produced in an acidic medium, pH naĂŻve melanoma cells acquire migratory and invasive capacities likely due to transfer of metastatic exosomal proteins, favoring cell motility and angiogenesis. A Prognoscan-based meta-analysis study of proteins enriched in acidic exosomes, identified 11 genes (HRAS, GANAB, CFL2, HSP90B1, HSP90AB1, GSN, HSPA1L, NRAS, HSPA5, TIMP3, HYOU1), significantly correlating with poor prognosis, whose high expression was in part confirmed in bioptic samples of lymph node metastases. Conclusions: A crucial step of melanoma progression does occur at melanoma intermediate -stage, when extracellular acidic pH induces an abundant release and intra-tumoral uptake of exosomes. Such exosomes are endowed with pro-invasive molecules of clinical relevance, which may provide a signature of melanoma advancement
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