Stellar footprints of a variable G

Theories with varying gravitational constant $G$ have been studied since long time ago. Among them, the most promising candidates as alternatives of the standard General Relativity are known as scalar-tensor theories. They provide consistent descriptions of the observed universe and arise as the low energy limit of several pictures of unified interactions. Therefore, an increasing interest on the astrophysical consequences of such theories has been sparked over the last few years. In this essay we comment on two methodological approaches to study evolution of astrophysical objects within a varying-$G$ theory, and the particular results we have obtained for boson and white dwarf stars.Comment: This essay received Honorable Mention in the 1999 Essay Competition of the Gravity Research Foundatio

Tecnologie per la didattica musicale: un'esperienza con la realtà virtuale

La mobile virtual reality (VR) sta diventando sempre pi\uf9 popolare e accessibile a tutti coloro che possiedono un nuovo smartphone. In particolare, la didattica digitale pu\uf2 trarre vantaggio dall'interazione naturale e dall'immersione in ambienti virtuali, a partire dalla scuola primaria. Questo articolo presenta un quadro tecnico e metodologico a supporto dell'uso della mobile virtual reality nell'istruzione primaria, volto a migliorare l'apprendimento musicale in termini di ascolto attivo, attenzione e tempo. Viene innanzitutto presentata un'applicazione multipiattaforma chiamata VR4EDU, di cui si descrivono le scelte di progetto e lo sviluppo delle applicazioni di virtual reality, con particolare attenzione a una innovativa soluzione di "locomozione virtuale" che risulta essere intuitiva e usabile. Le applicazioni di VR4EDU possono funzionare su hardware a basso costo, diventando quindi appetibili per un uso didattico. L'approccio proposto \ue8 stato validato tramite uno studio con due classi dell'ultimo anno di scuola primaria, incentrato sull'identificazione e l'apprendimento dei generi musicali. Una valutazione preliminare dei risultati mostra un miglioramento nell'apprendimento della caratterizzazione del genere rispetto alle lezioni tradizionali basate su materiale stampato e ascolto passivo

The white collar complex is essential for sexual reproduction but dispensable for conidiation and invasive growth in Fusarium verticillioides

Fvwc1 and Fvwc2, orthologues of the wc-1 and wc-2 genes encoding for proteins of the white collar complex (WCC) in Neurospora crassa were cloned from Fusarium verticillioides and lack-of-function wc mutants were obtained by targeted gene disruption. Photo-conidiation was found to be absent in F. verticillioides, on the contrary, the wild type strain produced less conidia under continuous illumination than in the dark. Inactivation of any of the wc genes led to total female sterility, without affecting male fertility or asexual conidiation. No loss in colonization capability/invasive growth of the wc mutants was observed, when assessed on tomato fruits. Both Fvwc1 and Fvwc2 showed constitutive expression in the wild type cultures incubated in the dark and exposure to light caused only negligible increases in their transcription. Both Fvwc1 and Fvwc2 were down-regulated in a ΔFvmat1-2-1 gene disruption mutant, lacking a functional mating type (mat1-2-1) gene, suggesting that the MAT1-2-1 product has a positive regulatory effect on the white collar genes

Association of kidney disease measures with risk of renal function worsening in patients with type 1 diabetes

Background: Albuminuria has been classically considered a marker of kidney damage progression in diabetic patients and it is routinely assessed to monitor kidney function. However, the role of a mild GFR reduction on the development of stage 653 CKD has been less explored in type 1 diabetes mellitus (T1DM) patients. Aim of the present study was to evaluate the prognostic role of kidney disease measures, namely albuminuria and reduced GFR, on the development of stage 653 CKD in a large cohort of patients affected by T1DM. Methods: A total of 4284 patients affected by T1DM followed-up at 76 diabetes centers participating to the Italian Association of Clinical Diabetologists (Associazione Medici Diabetologi, AMD) initiative constitutes the study population. Urinary albumin excretion (ACR) and estimated GFR (eGFR) were retrieved and analyzed. The incidence of stage 653 CKD (eGFR < 60 mL/min/1.73 m2) or eGFR reduction > 30% from baseline was evaluated. Results: The mean estimated GFR was 98 \ub1 17 mL/min/1.73m2 and the proportion of patients with albuminuria was 15.3% (n = 654) at baseline. About 8% (n = 337) of patients developed one of the two renal endpoints during the 4-year follow-up period. Age, albuminuria (micro or macro) and baseline eGFR < 90 ml/min/m2 were independent risk factors for stage 653 CKD and renal function worsening. When compared to patients with eGFR > 90 ml/min/1.73m2 and normoalbuminuria, those with albuminuria at baseline had a 1.69 greater risk of reaching stage 3 CKD, while patients with mild eGFR reduction (i.e. eGFR between 90 and 60 mL/min/1.73 m2) show a 3.81 greater risk that rose to 8.24 for those patients with albuminuria and mild eGFR reduction at baseline. Conclusions: Albuminuria and eGFR reduction represent independent risk factors for incident stage 653 CKD in T1DM patients. The simultaneous occurrence of reduced eGFR and albuminuria have a synergistic effect on renal function worsening

One billion Euro program for early childcare services in Italy

In 2007 the Italian central government started a program by transferring funds to regional governments to develop both private and public early childcare services. Exploiting the different timing of program implementation across regions, we evaluate its effectiveness in boosting the public supply of early childhood educational services. We find that the ratio between the available slots in public early childhood education and the population of those aged 0-2 increased by 18.1% three years after the start of the program, with respect to the pre-program level. The program impact was however nil in the South and totally driven by the Center-North