1,633 research outputs found

    Analysis of the coupled effect of steel studs and surface emissivity on internal insulation systems performance

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    Many kinds of insulation systems have been developed and applied over the years to all the constructive elements of the building, but the two most used strategies remain the external and internal insulation of vertical walls. However, about the latter often a significant issue is neglected: the overestimation of the thermal performance by disregarding the contribution of construction elements. Usually a uniform stratigraphy of the wall is considered and the evaluation of the performance of a non-uniform one leads to erroneous results about the overall behavior of the system. In this paper, we developed a different approach considering the presence of the steel studs used to attach this package to the existing wall and their influence on the thermal behavior of the structure. Through both experimental and numerical analysis, the possible application of low-e sheets inside the air cavity in various configurations and with different thicknesses of insulation is also taken into account. Results showed that neglecting the presence of the steel studs leads to an erroneous evaluation of the conductance of the refurbished wall with errors reaching up to 28.0% in low-e high-insulated cases. This work highlights how careful the designers have to be when using standard formulas to compute the thermal resistance of internal insulation wall systems

    Salivary cytokines as biomarkers for oral squamous cell carcinoma: A systematic review

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    The prognosis of patients with oral squamous carcinoma (OSCC) largely depends on the stage at diagnosis, the 5-year survival rate being approximately 30% for advanced tumors. Early diagnosis, including the detection of lesions at risk for malignant transformation, is crucial for limiting the need for extensive surgery and for improving disease-free survival. Saliva has gained popularity as a readily available source of biomarkers (including cytokines) useful for diagnosing specific oral and systemic conditions. Particularly, the close interaction between oral dysplastic/neoplastic cells and saliva makes such fluid an ideal candidate for the development of non-invasive and highly accurate diagnostic tests. The present review has been designed to answer the question: “Is there evidence to support the role of specific salivary cytokines in the diagnosis of OSCC?” We retrieved 27 observational studies satisfying the inclusion and exclusion criteria. Among the most frequent cytokines investigated as candidates for OSCC biomarkers, IL-6, IL-8, TNF-α are present at higher concentration in the saliva of OSCC patients than in healthy controls and may therefore serve as basis for the development of rapid tests for early diagnosis of oral cancer

    Poder desproteinizante de uma bentonita.

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    Fourier-Hermite decomposition of the collisional Vlasov-Maxwell system: Implications for the velocity-space cascade

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    Turbulence at kinetic scales is an unresolved and ubiquitous phenomenon that characterizes both space and laboratory plasmas. Recently, new theories, {\it in-situ} spacecraft observations and numerical simulations suggest a novel scenario for turbulence, characterized by a so-called phase space cascade -- the formation of fine structures, both in physical and velocity space. This new concept is here extended by directly taking into account the role of inter-particle collisions, modeled through the nonlinear Landau operator or the simplified Dougherty operator. The characteristic times, associated with inter-particle correlations, are derived in the above cases. The implications of introducing collisions on the phase space cascade are finally discussed

    Metabolic profiles of whole, parotid and submandibular/sublingual saliva

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    The detection of salivary molecules associated with pathological and physiological alterations has encouraged the search of novel and non-invasive diagnostic biomarkers for oral health evaluation. While genomic, transcriptomic, and proteomic profiles of human saliva have been reported, its metabolic composition is a topic of research: metabolites in submandibular/sublingual saliva have never been analyzed systematically. In this study, samples of whole, parotid, and submandibular/ sublingual saliva from 20 healthy donors, without dental or periodontal diseases, were examined by nuclear magnetic resonance. We identified metabolites which are differently distributed within the three saliva subtypes (54 in whole, 49 in parotid, and 36 in submandibular/sublingual saliva). Principal component analysis revealed a distinct cluster for whole saliva and a partial overlap for parotid and submandibular/sublingual metabolites. We found exclusive metabolites for each subtype: 2-hydroxy-3-methylvalerate, 3-methyl-glutarate, 3-phenylpropionate, 4-hydroxyphenylacetate, 4-hydroxyphenyllactate, galactose, and isocaproate in whole saliva; caprylate and glycolate in submandibular/sublingual saliva; arginine in parotid saliva. Salivary metabolites were classified into standard and non-proteinogenic amino acids and amines; simple carbohydrates; organic acids; bacterial-derived metabolites. The identification of a salivary gland-specific metabolic composition in healthy people provides the basis to invigorate the search for salivary biomarkers associated with oral and systemic diseases
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