338 research outputs found

    Sculture di Ravenna fra V e VI secolo

    Get PDF
    La scultura a Ravenna nei secoli V e VI testimonia il legame con l’Oriente. Ravenna fu prima capitale dell’impero romano d’Occidente. Successivamente fu conquistata da Teodorico e a seguito della guerra greco-gotica tornò sotto il controllo dell’impero romano con capitale Costantinopoli. La scultura riflette questo legame grazie all’importazione di manufatti. Ravenna nell’altomedioevo accolse le tendenze artistiche costantinopolitane rielaborandole verso indirizzi inediti che permettono di attribuire alle officine della città una volontaria e personale svolta verso la rappresentazione simbolica. La tendenza al simbolismo si rafforza fino al raggiungimento della pari dignità espressiva tra figura e simbolo.The sculpture in Ravenna in the fifth and sixth centuries testifies the link with the East. At first Ravenna was the capital of the Western Roman Empire, afterwards was conquered by Theodoric and than returned under the rule of the Roman Empire, whose capital was Constantinople, owing to the Gothic War. The sculpture reflects this relationship thanks to the import of works of art. In the high Middle Ages Ravenna received the growths of the byzantine art but elaborated them to new tendencies, which allow to ascribe to Ravenna a voluntary and peculiar turning-point to a symbolical representation. The tendency to symbolism becomes stronger up to achieve the equal expressive dignity between figure and symbol.

    Dual returns to experience

    Get PDF
    Summary of Banco de España Working Paper no. 221

    Dual returns to experience

    Get PDF
    En este documento estudiamos cómo la dualidad del mercado laboral afecta a la acumulación de capital humano y a las trayectorias salariales de los trabajadores jóvenes en España. Utilizando datos administrativos, seguimos a los trabajadores desde su entrada en el mercado laboral para medir la experiencia acumulada bajo diferentes tipos de contrato y estimamos sus rendimientos salariales. Documentamos rendimientos más bajos de la experiencia acumulada en contratos temporales en comparación con los contratos indefinidos, y mostramos que esta diferencia no se debe a la heterogeneidad inobservada de las empresas en las que trabajan ni a la calidad del emparejamiento. Por el contario, proporcionamos evidencia de que la brecha en los rendimientos se debe a una menor acumulación de capital humano cuando se trabaja con contratos temporales. Esta diferencia se amplía con la habilidad del trabajador, lo que indica una complementariedad entre experiencia y capacidad de aprendizaje. Nuestros resultados sugieren que el uso generalizado de contratos temporales reduce la adquisición de habilidades de los trabajadores altamente cualificados, lo que frena el crecimiento salarial a lo largo de su carrera profesional hasta en 16 puntos porcentuales 15 años después de su entrada al mercado laboral.This paper studies how labor market duality affects human capital accumulation and the wage trajectories of young workers in Spain. Using rich administrative data, we follow workers from their entry into the labor market to measure the experience accumulated under different contractual arrangements and we estimate their wage returns. We document lower returns on experience accumulated under fixed-term contracts compared with permanent contracts and show that this difference is not due to unobserved firm heterogeneity or the quality of the matching. Instead, we provide evidence that the gap in returns is due to lower human capital accumulation while working under fixed-term contracts. This difference widens with worker skill, suggesting that experience and skill-learning are complementary. Our results suggest that the widespread use of fixed-term work arrangements reduces the skill acquisition of highly-skilled workers, holding back life-cycle wage growth by up to 16 percentage points 15 years after their entry into the labor market

    Medium-Long-Term Clinical and Radiographic Outcomes of Minimally Invasive Distal Metatarsal Metaphyseal Osteotomy (DMMO) for Central Primary Metatarsalgia: Do Maestro Criteria Have a Predictive Value in the Preoperative Planning for This Percutaneous Technique?

    Get PDF
    The purpose of this prospective study was first to evaluate the safety and effectiveness of Minimally Invasive Distal Metatarsal Metaphyseal Osteotomy (DMMO) in treating central metatarsalgia, identifying possible contraindications. The second objective was to verify the potential of DMMO to restore a harmonious forefoot morphotype according to Maestro criteria. Methods. A consecutive series of patients with metatarsalgia was consecutively enrolled and treated by DMMO. According to Maestro criteria, preoperative planning was carried out by both clinical and radiological assessment. Patient demographic data, AOFAS scores, 17-FFI, MOXFQ, SF-36, VAS, and complications were recorded. Maestro parameters, relative morphotypes, and bone callus formation were assessed. Statistical analysis was carried out (p<0.05). Results. Ninety-three patients (93 feet) with a mean age of 62.4 (31-87) years were evaluated. At mean follow-up of 58.7 (36-96) months, all of the clinical scores improved significantly (p<0.0001). Most of the osteotomies (76.3%) had healed by 3-month follow-up, while ideal harmonious morphotype was restored only in a few feet (3.2%). Clinical and radiological outcomes were not different based on principal demographic parameters. Long-term complications were recorded in 12 cases (12.9%). Conclusion. DMMO is a safe and effective method for the treatment of metatarsalgia. Although Maestro criteria were useful to calculate the metatarsal bones to be shortened and a significant clinical improvement of all scores was achieved, the ideal harmonious morphotype was restored only in a few feet. Hence, our data show that Maestro criteria did not have a predictive value in clinical outcomes of DMM

    Enabling the Circular Economy transition: a sustainable lean manufacturing recipe for Industry 4.0

    Get PDF
    AbstractOver the past 10 years, the concepts and objectives of circular economy have been increasingly detailed and become strategic issues of international, European, and national policies. However, the transition towards circular production models continues to be affected by several barriers and critical factors that make the transition difficult to achieve. The paper tries to design a relationship between sustainable production and lean production, highlighting the opportunity to invest in reverse‐logistics and how Industry 4.0 system represents a breeding ground for circular economy targets application. The aim of the current study is to examine the relationships among sustainable production, lean production, and Industry 4.0 in order to evidence the need to adopt a lean methodology and Industry 4.0 technologies in a sustainable development perspective for companies. Following a holistic vision, the authors summarize the production principles and formulas, which, although in parallel, lead to similar results and therefore represent the pillars of a competitive and sustainable business. In conclusion, exploring the circular economy principles and production chain model, challenges, opportunities, and future outlooks are formulated

    Transfemoral versus transcarotid access for transcatheter aortic valve

    Get PDF
    Objectives: To compare the outcomes after transcatheter aortic valve replacement (TAVR) through a transfemoral (TF) and transcarotid (TC) access at our institution.Methods: From January 2014 to January 2020, 62 TC-TAVR and 449 TF-TAVR were performed using 2 prosthesis devices (Edwards SAPIEN 3, n = 369; Medtronic Evo-lut R, n = 142). Propensity score matching was used to adjust for imbalance in the baseline characteristics of the study groups.Results: Propensity score matching provided 62 matched pairs with comparable operative risk (mean European System for Cardiac Operative Risk Evaluation II, TC-TAVR 7.6% vs TF-TAVR 6.6%, P = .17). Thirty-day mortality (4.8% vs 3.2%, P = 1.00) and 2-year mortality (11.3% vs 12.9%, P = .64) after TC-TAVR were com-parable with TF-TAVR. Strokes were numerically more frequent after TC-TAVR compared with TF-TAVR (3.2% vs 0%, P = .23), but the difference did not reach statistical significance. TF-TAVR was associated with a significantly greater risk of permanent pacemaker implantation (29.0% vs 12.9%, P = .04) compared with TC-TAVR. Other complications were not frequent and were similarly distributed be-tween the matched groups.Conclusions: TC access for TAVR was associated with satisfactory results compared to the femoral access. TC-TAVR could be considered a valid and safe alternative to TF-TAVR when femoral access is contraindicated. (JTCVS Techniques 2022;15:46-53)Peer reviewe

    Geomaterials and decay forms of the coastal towers of Piscinni and Foghe, Weastern Sardinia

    Get PDF
    [EN] The distribution of Coastal Towers in Sardinia testify that foreign invasions, which occurred several times over the centuries, were particularly frequent and dangerous. The beginning of the eighth century signed an increase of the attacks from the sea. The most of Coastal Towers were built in the period of Spanish rule, from 1583 to 1720. Despite numerous restorations over the years, many of these defensive structures are in critical conditions, some also affected by structural collapse. The building materials are closely related to local geological outcrops, and consist of sedimentary, magmatic and metamorphic rocks. Study of different lithotypes allowed assessing the vulnerability of different materials in different environmental conditions. Salts, transported by aerosols and deposited inside the porous structures, are the principal cause of decay of the building materials. Chemical-physical and mineralogical-petrographic analyses, performed on some Towers allowed making some general assessments on their conservation status and restoration projects.Carcangiu, G.; Meloni, P.; Palomba, M.; Cocco, O.; Sitzia, F.; Murru, A.; Carboni, M.... (2015). Geomaterials and decay forms of the coastal towers of Piscinni and Foghe, Weastern Sardinia. En Defensive architecture of the mediterranean: XV to XVIII centuries. Vol. I. Editorial Universitat Politècnica de València. 345-352. https://doi.org/10.4995/FORTMED2015.2015.1753OCS34535

    Ln(III) Complexes Embedded in Biocompatible PLGA Nanoparticles as Potential Vis-to-NIR Optical Probes

    Get PDF
    In this contribution, we present the spectroscopic study of two NIR emitting hydrophobic heteroleptic (R,R)-YbL1(tta) and (R,R)-NdL1(tta) complexes (with tta = 2-thenoyltrifluoroacetonate and L1 = N,N0 -bis(2-(8-hydroxyquinolinate)methylidene)-1,2-(R,R or S,S)-cyclohexanediamine), both in methanol solution and embedded in water dispersible and biocompatible poly lactic-co-glycolic acid (PLGA) nanoparticles. Thanks to their absorption properties in a wide range of wavelengths extending from the UV up to the blue and green visible regions, the emission of these complexes can be effectively sensitized using visible radiation, which is much less harmful to tissues and skin than the UV one. The encapsulation of the two Ln(III)-based complexes in PLGA allows us to preserve their nature, making them stable in water and to test their cytotoxicity on two different cell lines, with the aim of using them in the future as potential bioimaging optical probes

    Durability of repair mortars used in restoration of a Sardinian coastal tower: assessment after ten years

    Full text link
    [EN] This study reports the results of investigations on conservation conditions of an ancient tower, called Torre del Pozzo, located in the S-W coast of Sardinia, restored about ten years ago. The tower suffers from serious problems related to vulnerability of building materials, particularly limestone and sandstones and aerial lime mortar with poor physical-mechanical properties. Over the centuries the materials were subjected to aggressive actions (wind corrasion and salt crystallization) causing an intense erosion of the walls with consequent partial collapse of the structure. About ten years ago a restoration involved the mortars and only the replacement and integration of ashlars deteriorated. After about 10 years from this intervention, some inspections have been carried out in order to assess the effectiveness of the intervention and the state of preservation of the tower. This paper focuses on analyses and tests carried out to assess condition and durability of the repair mortars.Meloni, P.; Carcangiu, G.; Palomba, M.; Enzo, S.; Carboni, M.; Cocco, O.; Casti, M.... (2015). Durability of repair mortars used in restoration of a Sardinian coastal tower: assessment after ten years. En Defensive architecture of the mediterranean: XV to XVIII centuries. Vol. II. Editorial Universitat Politècnica de València. 397-44. https://doi.org/10.4995/FORTMED2015.2015.1761OCS3974
    corecore