201 research outputs found
Desde adentro: una mirada del Art Brut en Uruguay
No full textNo disponible.Sonido: Victoria Cánepa; postproducción: Daniela Castillo; dirección, producción, postproducción: Ana Laura Durante; producción, fotografía, postproducción: Daniela Luongo Akiki; fotografía, Iluminación, postproducción: Sebastián Moroni; elenco: Isabel Cavadini, Pablo Thiago Rocca, Oscar Caballero, Jesús, Daniel, Cristina Ottem, Eduardo Cervieri, Luis Fonseca, Alberto Méndez
The returns to tertiary education in Italy and Europe
No full textIn this paper we use the EU-SILC data 2005 to estimate the private rates of return to higher education in 22 European countries. By implementing a Heckman selection model and an instrumental variables estimator we study the effects of schooling on employment and wages and compare them across European countries. Our results show a great deal of heterogeneity in the rate-of-return estimates across countries. Although a clear grouping of countries does not emerges, we observe that the returns to tertiary education appear generally high for Eastern countries and low for Nordic countries whereas the Mediterranean and Continental European countries mostly exhibit an intermediate position
Global well-posedness and interior regularity of 2D Navier–Stokes equations with stochastic boundary conditions
No full textThe paper is devoted to the analysis of the global well-posedness and the interior regularity of the 2D Navier–Stokes equations with inhomogeneous stochastic boundary conditions. The noise, white in time and coloured in space, can be interpreted as the physical law describing the driving mechanism on the atmosphere–ocean interface, i.e. as a balance of the shear stress of the ocean and the horizontal wind force.Analysi
The role of the substrate in Graphene/Silicon photodiodes
No full textThe Graphene/Silicon (Gr/Si) junction can function as a Schottky diode with performances strictly related to the quality of the interface. Here, we focus on the substrate geometry and on its effects on Gr/Si junction physics. We fabricate and study the electrical and optical behaviour of two types of devices: one made of a Gr/Si planar junction, the second realized with graphene on an array of Si nanotips. We show that the Gr/Si flat device exhibits a reverse photocurrent higher than the forward current and achieves a photoresponsivity of 2.5 A/W. The high photoresponse is due to the charges photogenerated in Si below a parasitic graphene/SiO2/Si structure, which are injected into the Gr/Si junction region. The other device with graphene on Si-tips displays a reverse current that grows exponentially with the bias. We explain this behaviour by taking into account the tip geometry of the substrate, which magnifies the electric field and shifts the Fermi level of graphene, thus enabling fine-tuning of the Schottky barrier height. The Gr/Si-tip device achieves a higher photoresponsivity, up to 3 A/W, likely due to photocharge internal multiplication
Model-independent cosmographic constraints from DESI 2024
No full textContext. We explore model-independent constraints on the Universe kinematics up to the snap and jerk hierarchical terms, considering the latest baryon acoustic oscillation (BAO) release provided by the DESI collaboration.Aims. We intend to place novel and more stringent constraints on the cosmographic series, incorporating three combinations of data catalogs: the first made by BAO and observational cosmic chronometers, the second made by BAO and type Ia supernovae, and the last including all the cited data sets.Methods. Considering the latest BAO data provided by the DESI collaboration and tackling the rd parameter to span within the range [144,152] Mpc, with a fixed step of δrd = 2 Mpc, we employed Monte Carlo Markov chain analyses based on the Metropolis algorithm to fix novel bounds on the cosmographic series, fixing the deceleration, q0 , the jerk, j0 , and the snap, s0, parameters, up to the 2σ level. A comparison between the results of the Planck satellite with those obtained by the DESI collaboration is also reported.Results. Our findings showcase a significant departure in terms of j0 even at the 1σ confidence level, albeit compatible with the ACDM paradigm in regard to q0 and s0 at the 2σ level. Analogously, the h0 tension appears alleviated in the second hierarchy when including snap.Conclusions. Our method excludes models that significantly depart from the standard cosmological model. Particularly, direct comparisons with the ACDM and wCDM models and the Chevallier-Polarski-Linder parameterisation are explored, which definitively favour the wCDM scenario over other approaches, contradicting the findings of the original DESI collaboration.Key words: cosmological parameters / cosmology: theory / dark energy / distance scale / large-scale structure of Universe★ Corresponding author; [email protected]
(Ri-)Scrivere di santi: sulle tracce di Agnese
No full textL’articolo, seguendo una sollecitazione di Gennaro Luongo, recentemente scomparso, si interessa al dossier agiografico di Agnese. L’autrice lo ripercorre fra storia e leggenda, documenti letterari e testimonianze monumentali, iconografia e pratiche devozionali. Ciò le consente di mettere in evidenza le trasformazioni e continue ri-funzionalizzazioni del personaggio, nonché di avanzare alcune ipotesi sulle ragioni che presiedettero a questi continui processi di rilettura.The article following a solicitation by Gennaro Luongo, recently deceased, deals with the hagiographic dossier of Agnese. The author traces it between history and legend, literary documents and monumental evidences, iconography and devotional practices. This allows her to highlight the transformations (modifications) and continuous re-functionalizations of the character, as well as to advance some hypotheses on/regarding the reasons that presided over these continuous re-reading processes
I-V and C-V Characterization of a High-Responsivity Graphene/Silicon Photodiode with Embedded MOS Capacitor
No full textWe study the effect of temperature and light on the I-V and C-V characteristics of a graphene/silicon Schottky diode. The device exhibits a reverse-bias photocurrent exceeding the forward current and achieves a photoresponsivity as high as 2.5 A/W. We show that the enhanced photocurrent is due to photo-generated carriers injected in the graphene/Si junction from the parasitic graphene/SiO2/Si capacitor connected in parallel to the diode. The same mechanism can occur with thermally generated carriers, which contribute to the high leakage current often observed in graphene/Si junctions
Field Emission from Carbon Nanostructures
No full textField emission electron sources in vacuum electronics are largely considered to achieve faster response, higher efficiency and lower energy consumption in comparison with conventional thermionic emitters. Carbon nanotubes had a leading role in renewing attention to field emission technologies in the early 1990s, due to their exceptional electron emitting properties enabled by their large aspect ratio, high electrical conductivity, and thermal and chemical stability. In the last decade, the search for improved emitters has been extended to several carbon nanostructures, comprising carbon nanotubes, either individual or films, diamond structures, graphitic materials, graphene, etc. Here, we review the main results in the development of carbon-based field emitters
Fusarium oxysporum f. Sp. melonis-melon interaction: Effect of grafting combination on pathogen gene expression
No full textVery early onset of autoimmune thyroiditis in a toddler with severe hypothyroidism presentation: a case report
No full textBackground: In infants under 3 years of age acquired primary hypothyroidism caused by autoimmune thyroiditis is very rare. Hypothyroidism can manifest with different signs and symptoms and has a wide range of presentations from subclinical hypothyroidism to overt form. We describe a child with acquired autoimmune thyroiditis during a very early period of life and with a severe hypothyroidism presentation. Case presentation: A 22-month-old white male patient with normal neonatal screening presented with a six-month history of asthenia and cutaneous pallor. At general clinical and biochemical exams he showed weight gain, statural growth deceleration, poor movements, sleepy expression, instability while walking, myxoedema, bradycardia, open anterior fontanelle, changes in the face habitus, macrocytic anaemia, ascites, and high CPK, creatinine and cholesterol levels. Acquired autoimmune thyroiditis was the final diagnosis. The thyroxine replacement therapy normalized all the clinical and biochemical abnormalities but at the age of 30 months his mental age showed a delay of 6 months. Conclusions: Our case could give useful learning points: i) although the screening for congenital hypothyroidism is routinely performed, a severe hypothyroidism (for example due to autoimmune thyroiditis) can anyway occur early in life and the clinicians should consider this possibility; ii) hypothyroidism can have a misleading and multi-face clinical presentation; iii) anemia, rhabdomyolysis and high creatinine levels should always include the hypothyroidism in the differential diagnosis; iv) thyroxine replacement therapy is able to revert all the clinical manifestations related to the hypothyroidism; v) evaluating the patient's previous pictures could play an important role in resolving a diagnostic conundrum
- …
