153 research outputs found

    New Insights to Characterize Paint Varnishes and to Study Water in Paintings by Nuclear Magnetic Resonance Spectroscopy (NMR)

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    Paintings are complex multi-layered systems made of organic and inorganic materials. Several factors can affect the degradation of paintings, such as environmental conditions, past restoration works and, finally, the type of painting technique and the art materials used over the centuries. The chemical–physical characterization of paintings is a constant challenge that requires research into and the development of novel analytical methodologies and processes. In recent years, solvents and water-related issues in paintings are attracting more attention, and several studies have been focused on analyzing the interaction between water molecules and the constitutive materials. In this study, recent applications applying different NMR methodologies were shown, highlighting the weakness and the strength of the techniques in analyzing paintings. In particular, the study of water and its diffusive interactions within wall and oil paintings was performed to prove how the portable NMR can be used directly in museums for planning restoration work and to monitor the degradation processes. Furthermore, some preliminary results on the analysis of varnishes and binders, such us linseed oil, shellac, sandarac and colophony resins, were obtained by 1H HR-MAS NMR spectroscopy, highlighting the weakness and strengths of this technique in the field of conservation science

    Análisis de las facultades de organización, dirección y disciplinarias del empleador frente al cambio repentino y masivo de la presencialidad al teletrabajo

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    Trabajo final de posgrado (Especialización en Derecho del Trabajo y la Seguridad Social) -- Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina, 2022.Este trabajo tiene por finalidad describir y analizar las Facultades de organización, dirección y disciplinarias del empleador respecto del trabajador desde la virtualidad y el derecho a la desconexión de los mismos. Analizar cuales son las limitaciones al ejercicio de las referidas Facultades del empleador considerando los derechos del trabajador a la desconexión digital, a la intimidad y privacidad, teniendo como herramientas el uso de las tecnologías de información. En efecto, analizar de que manera las nuevas tecnologías pueden servir de instrumentos facilitadores para el ejercicio de las Facultades sin vulnerar los derechos de las personas teletrabajadoras. Describir el marco legal regulatorio, antecedentes jurisprudenciales y las herramientas de uso especifico utilizadas en las empresas para su ejercicio. Este trabajo lleva a comprender que existen nuevas formas de dependencia jurídico-laboral en virtud del advenimiento de las nuevas tecnologías, pero, así como se han facilitado estas nuevas formas de realizar las tareas han traído aparejados cambios en cuanto a metodologías y problemas legales que es preciso solucionar.Fil: Proietti, Valeria Silvina. Universidad Nacional de Córdoba. Facultad de Ciencias Económicas; Argentina

    Unilateral NMR: a Noninvasive Tool for Monitoring In Situ the Effectiveness of Intervention to Reduce the Capillary Raise of Water in an Ancient Deteriorated Wall Painting

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    Portable unilateral NMR was used to quantitatively map in a fully noninvasive way the moisture distribution in an ancient deteriorated wall painting before and after an intervention to reduce the capillary raise of water through the wall. Maps obtained at a depth of 0.5 cm clearly showed the path of the capillary raise and indicated that, after the intervention, the moisture level was reduced. Maps obtained by measuring the first layers of the wall painting were affected by the critical environmental conditions of the second hypogeous level of St. Clement Basilica, Rome, and by the presence of salts efflorescence and encrustations on the surface of the wall painting. The morphology and the elemental composition of salts investigated by SEM-EDS indicated that efflorescences and encrustations were mostly constituted of gypsum and calcite. The presence of these salts is explained with the presence of high concentration of carbon dioxide and sulphur-rich particles due to pollution which, along with the high-moisture level and the extremely feeble air circulation, cause recarbonation and sulphation processes on the plaster surface

    Moisture Damage in Ancient Masonry: A Multidisciplinary Approach for In Situ Diagnostics

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    San Nicola in Carcere, one of the minor basilicas in the historical center of Rome, was the location of a wide investigation campaign of the water-related deterioration causes, present in the lower sector of the apse and adjacent pillars, affected by water infiltrations, mould and salt efflorescence. The results obtained identify the presence of water content and related effects mainly on the sides of the apsidal wall. This work focuses on the use of five Non-Destructive Techniques (NDT) and intends to show the gains obtained by integrating widely interdisciplinary methods, namely the Infrared Thermography (IRT), the Unilateral Nuclear Magnetic Resonance (Unilateral NMR), the Acoustic Tomography (AT), the Acoustic Imaging (AI) and the Laser-Induced Fluorescence (LIF). All the techniques contribute to the rapid, non-invasive and early identification of the moisture distribution, while some of them (LIF and AI) also address the determination of some moisture effects. The integrated use of different techniques helps to take the multidisciplinary point of view necessary to formulate an effective restoration intervention based on a sound scientific rationale; nonetheless, it allows to experiment a holistic approach, verifying the potential of a wide range of NDTs available within the context of a restoration yard

    Low cancer yield in pi-rads 3 upgraded to 4 by dynamic contrast-enhanced mri. is it time to reconsider scoring categorization

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    Objectives: To evaluate MRI diagnostic performance in detecting clinically significant prostate cancer (csPCa) in peripheral-zone PI-RADS 4 lesions, comparing those with clearly restricted diffusion (DWI-score 4), and those with equivocal diffusion pattern (DWI-score 3) and positive dynamic contrast-enhanced (DCE) MRI. Methods: This observational prospective study enrolled 389 men referred to MRI and, if positive (PI-RADS 3 with PSA-density [PSAD] ≥ 0.15 ng/mL/mL, 4 and 5), to MRI-directed biopsy. Lesions with DWI-score 3 and positive DCE were classified as "PI-RADS 3up," instead of PI-RADS 4. Univariable and multivariable analyses were implemented to determine features correlated to csPCa detection. Results: Prevalence of csPCa was 14.5% and 53.3% in PI-RADS categories 3up and 4, respectively (p < 0.001). MRI showed a sensitivity of 100.0%, specificity 40.9%, PPV 46.5%, NPV 100.0%, and accuracy 60.9% for csPCa detection. Modifying the threshold to consider MRI positive and to indicate biopsy (same as previously described, but PI-RADS 3up only when associated with elevated PSAD), the sensitivity changed to 93.9%, specificity 57.2%, PPV 53.0%, NPV 94.8%, and accuracy 69.7%. Age (p < 0.001), PSAD (p < 0.001), positive DWI (p < 0.001), and PI-RADS score (p = 0.04) resulted in independent predictors of csPCa. Conclusions: Most cases of PI-RADS 3up were false-positives, suggesting that upgrading peripheral lesions with DWI-score 3 to PI-RADS 4 because of positive DCE has a detrimental effect on MRI accuracy, decreasing the true prevalence of csPCa in the PI-RADS 4 category. PI-RADS 3up should not be upgraded and directed to biopsy only if associated with increased PSAD. Key points: • As per PI-RADS v2.1 recommendations, in case of a peripheral zone lesion with equivocal diffusion-weighted imaging (DWI score 3), but positive dynamic contrast-enhanced (DCE) MRI, the overall PI-RADS score should be upgraded to 4. • The current PI-RADS recommendation of upgrading PI-RADS 3 lesions of the peripheral zone to PI-RADS 4 because of positive DCE decreased clinically significant prostate cancer detection rate in our series. • According to our results, the most accurate threshold for setting indication to prostate biopsy is PI-RADS 3 or PI-RADS 3 with positive DCE both associated with increased PSA density

    Spatially, Temporally, and Quantitatively Controlled Delivery of Broad Range of Molecules into Selected Cells through Plasmonic Nanotubes

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    A Universal plasmonic/microfluidic platform for spatial and temporal controlled intracellular delivery is described. The system can inject/transfect the desired amount of molecules with an efficacy close to 100%. Moreover, it is highly scalable from single cells to large ensembles without administering the molecules to an extracellular bath. The latter enables quantitative control over the amount of injected molecules

    Adherence to antithrombotic therapy guidelines improves mortality among elderly patients with atrial fibrillation: insights from the REPOSI study

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    Atrial fibrillation (AF) is associated with a substantial risk of thromboembolism and mortality, significantly reduced by oral anticoagulation. Adherence to guidelines may lower the risks for both all cause and cardiovascular (CV) deaths. Methods: Our objective was to evaluate if antithrombotic prophylaxis according to the 2012 European Society of Cardiology (ESC) guidelines is associated to a lower rate of adverse outcomes. Data were obtained from REPOSI; a prospective observational study enrolling inpatients aged ≥65 years. Patients enrolled in 2012 and 2014 discharged with an AF diagnosis were analysed. Results: Among 2535 patients, 558 (22.0 %) were discharged with a diagnosis of AF. Based on ESC guidelines, 40.9 % of patients were on guideline-adherent thromboprophylaxis, 6.8 % were overtreated, and 52.3 % were undertreated. Logistic analysis showed that increasing age (p = 0.01), heart failure (p = 0.04), coronary artery disease (p = 0.013), peripheral arterial disease (p = 0.03) and concomitant cancer (p = 0.003) were associated with non-adherence to guidelines. Specifically, undertreatment was significantly associated with increasing age (p = 0.001) and cancer (p < 0.001), and inversely associated with HF (p = 0.023). AF patients who were guideline adherent had a lower rate of both all-cause death (p = 0.007) and CV death (p = 0.024) compared to those non-adherent. Kaplan–Meier analysis showed that guideline-adherent patients had a lower cumulative risk for both all-cause (p = 0.002) and CV deaths (p = 0.011). On Cox regression analysis, guideline adherence was independently associated with a lower risk of all-cause and CV deaths (p = 0.019 and p = 0.006). Conclusions: Non-adherence to guidelines is highly prevalent among elderly AF patients, despite guideline-adherent treatment being independently associated with lower risk of all-cause and CV deaths. Efforts to improve guideline adherence would lead to better outcomes for elderly AF patient

    Low elasticity of thyroid nodules at ultrasound elastography is correlated with malignancy, degree of fibrosis and high expression of galectin-3 and fibronectin-1

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    ackground: Thyroid ultrasound (US) elastography provides an estimation of tissue stiffness and is helpful to differentiate malignant from benign lesions. Tissue proprieties and molecules causing stiffness are not established. The aim of the study was to correlate US elastography findings with tissue properties in thyroid nodules. Methods: A total of 115 thyroid nodules from 112 patients who underwent surgery for the presence of Thy 3 (indeterminate) cytology (n = 67), Thy 4-5 (suspicious - indicative of carcinoma) cytology (n = 47), or large goiter in the presence of Thy 2 cytology (n = 1) and suspicious US features were examined by US elastography. Tissues obtained after surgery were characterized for cell number, microvessel density, fibrosis, and expression of galectin-3 (Gal-3) and fibronectin-1 (FN-1). Results: Low elasticity on qualitative US elastography (LoEl) was found in 66 nodules (one benign and 65 carcinomas); high elasticity (HiEl) was found in 49 nodules (46 benign and three carcinomas; p &lt; 0.0001). Quantitative analysis, performed in 24 nodules and expressed as elastic ratio between the strain of the nodule and that of the surrounding thyroid parenchyma, showed a mean of 1.90 (interquartile range [IQR] 1.18-2.77) in 14 nodules with LoEl, and a mean of 1.01 (IQR 0.91-1.10) in 10 nodules with HiEl (p = 0.002). Stiffness did not correlate with cell number and was inversely correlated with microvessel density. Fibrosis was higher in nodules with LoEl than in those with HiEl (p = 0.009) and in carcinomas than in benign nodules (p = 0.02). Fibrosis was higher in nodules with high expression of Gal-3 (p &lt; 0.001) and FN-1 (p = 0.004). Fibrosis and expression of Gal-3 and FN-1 were higher in the classic compared with the follicular variant of papillary thyroid carcinoma and lower in follicular adenomas. Conclusions: Low elasticity at US elastography is highly correlated with malignancy. Nodule stiffness is correlated with fibrosis and expression of Gal-3 and FN-1. These features are more evident in the classic than in the follicular variant of papillary thyroid carcinoma

    L’ecografia polmonare per il pediatra

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    L’ecografia polmonare si sta dimostrando una metodica di grande interesse e negli ultimi anni si è assistito ad un fiorire di pubblicazioni sull’argomento. In particolar modo, la sua semplicità d’uso e d’apprendimento ne stanno garantendo una forte diffusione. Se paragonata poi alla radiografia del torace, la più diffusa indagine di imaging in pneumologia pediatrica, l’ecografia polmonare appare molto promettente. In questo articolo ci prefiggiamo di fornire alcune informazioni basilari sull’ecografia polmonare che possono però diventare un importante spunto per la comprensione di questa innovativa metodica.The lung ultrasound is object of a strong interest and in the lasts years there has been a huge increase in the number of publications on the topic. Its simplicity of use and learning are ensuring it an increasingly widespread use. If compared to the chest radiograph, the most used imaging technique in pediatric pulmonology, lung ultrasound appears very promising. In this article we aim to provide some basic information on lung ultrasound that can become an important start point for understanding this innovative technique
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