Calamità naturali e assicurazione: elementi di analisi per una riforma

Private insurance markets provide insufficient coverage for risks coming from natural disasters. We argue that in such markets the typical market failure is mainly due to reasons other than asymmetric information. More specifically, the low probability of a disaster, together with the height of the economic damage normally involved and the strong correlation among individual risks raise the insurers’ and lower the potential clients’ reservation price. The solution recently provided within the market (the CAT bonds) is interesting but unsatisfactory. Therefore the intervention of the public sector is needed. After analyzing the experience of some countries (USA, France, Spain, Switzerland), we propose a reform plan for Italy that avoids the discretionary ex post public intervention, allows an inter-temporal risk diversification, and avoids the waste of resources in risk selection (a typical feature of the private provision of insurance).Insurance, Natural disasters, Public provision of services

Interplay of Quantum Confinement and Strain Effects in Type I to Type II Transition in GeSi Core-Shell Nanocrystals

The electronic properties of hydrogenated, spherical SiGe and GeSi core-shell nanocrystals, with a diameter ranging from 1.8 to 4.0 nm, are studied within density functional theory. Effects induced by quantum confinement and strain on the near band-edge state localization, as well as the band-offset properties between Si and Ge regions, are investigated in detail. On the one hand, we prove that SiGe core-shell nanocrystals always show a type II band-offset alignment, with the HOMO mainly localized on the Ge shell region and the LUMO mainly localized on the Si core region. On the other hand, our results point out that a type II offset cannot be observed in small (diameter less than 3 nm) GeSi core- shell nanocrystals. In these systems, quantum confinement and strain drive the near-band-edge states to be mainly localized on Ge atoms, i.e., in the core region. In larger GeSi core-shell nanocrystals, instead, the formation of a type II offset can be engineered by playing with both core and shell thickness. The factors which determine the band-offset character at the Ge/Si interface are discussed in detail

Probing coherence in metal absorption towards multiple images of strong gravitationally lensed quasars

We present a tomographic analysis of metal absorption lines arising from the circumgalactic medium (CGM) of galaxies at z~0.5-2, using Multi Unit Spectroscopic Explorer (MUSE) observations of two background quasars at z~2.2 and 2.8, which are two of the few currently known quasars with multiple images due to strong gravitational lensing by galaxy clusters at z~0.6 and 0.5, respectively. The angular separations between different pairs of quasar multiple images enable us to probe the absorption over transverse physical separations of ~0.4-150 kpc, which are based on strong lensing models exploiting MUSE observations. The fractional difference in rest-frame equivalent width (Delta Wr) of MgII, FeII, CIV absorption increases on average with physical separation, indicating that the metal-enriched gaseous structures become less coherent with distance, with a likely coherence length scale of ~10 kpc. However, Delta Wr for all the ions vary considerably over ~0.08-0.9, indicating a clumpy CGM over the full range of length scales probed. At the same time, paired MgII absorption is detected across ~100-150 kpc at similar line-of-sight velocities, which could be probing cool gas clouds within the same halo. No significant dependence of Delta Wr is found on the equivalent width and redshift of the absorbing gas and on the galaxy environment associated with the absorption. The high-ionization gas phase traced by CIV shows a higher degree of coherence than the low-ionization gas phase traced by MgII, with ~90 percent of CIV systems exhibiting Delta Wr <=0.5 at separations <=10 kpc compared to ~50 percent of MgII systems.Comment: 9 pages + appendix, 8 figures, accepted in MNRA

Altered Expression of the CB1 Cannabinoid Receptor in the Triple Transgenic Mouse Model of Alzheimer's Disease

The endocannabinoid system has gained much attention as a new potential pharmacotherapeutic target in various neurodegenerative diseases, including Alzheimer's disease (AD). However, the association between CB1 alterations and the development of AD neuropathology is unclear and often contradictory. In this study, brain CB1 mRNA and CB1 protein levels were analyzed in 3 × Tg-AD mice and compared to wild-type littermates at 2, 6 and 12 months of age, using in-situ hybridization and immunohistochemistry, respectively. Semiquantitative analysis of CB1 expression focused on the prefrontal cortex (PFC), prelimbic cortex, dorsal hippocampus (DH), basolateral amygdala complex (BLA), and ventral hippocampus (VH), all areas with high CB1 densities that are strongly affected by neuropathology in 3 × Tg-AD mice. At 2 months of age, there was no change in CB1 mRNA and protein levels in 3 × Tg-AD mice compared to Non-Tg mice in all brain areas analyzed. However, at 6 and 12 months of age, CB1 mRNA levels were significantly higher in PFC, DH, and BLA, and lower in VH in 3 × Tg-AD mice compared to wild-type littermates. CB1 immunohistochemistry revealed that CB1 protein expression was unchanged in 3 × Tg-AD at 2 and 6 months of age, while a significant decrease in CB1 receptor immunoreactivity was detected in the BLA and DH of 12-month-old 3 × Tg-AD mice, with no sign of alteration in other brain areas. The altered CB1 levels appear, rather, to be age-and/or pathology-dependent, indicating an involvement of the endocannabinoid system in AD pathology and supporting the ECS as a potential novel therapeutic target for treatment of AD

Safety and Efficacy of Surgery for Metastatic Tumor to the Pancreas: A Single-Center Experience

Pancreatic metastases from other neoplasms are rare. The role of surgery for this clinical entity is unclear. The aim of this study was to investigate the role of resection in patients with pancreatic secondary lesions. We observed 44 patients with pancreatic metastases from other tumors. Renal cell carcinoma was the most common primary tumor (n = 19, 43.2%). Thirty-seven patients underwent surgery, and pancreatic resection with curative intent was feasible in 35 cases. Fifteen patients (43.2%) experienced major postoperative complications (Clavien-Dindo > 2), and postoperative mortality rate was 5.4%. The median overall survival and disease-free survival were 38 (range 0–186) and 11 (range 0–186) months, respectively. Overall survival and disease-free survival were significantly longer for pancreatic metastases from renal cell carcinoma when compared to other primary tumors. Multivariate analysis confirmed a pathological diagnosis of metastasis from RCC as an independent prognostic factor for overall survival (OR 2.48; 95% CI, 1.00–6.14; p = 0.05). In conclusion, radical resection of metastases to the pancreas is feasible and safe, and may confer a survival benefit for selected patients. There is a clear benefit of metastasectomy in terms of patient survival for metastases from renal cell carcinoma, while for those with other primary tumors, surgery seems to be mainly palliative

The puzzling properties of the MACS1149-JD1 galaxy at z=9.11

We analyze new JWST NIRCam and NIRSpec data on the redshift 9.11 galaxy MACS1149-JD1. Our NIRCam imaging data reveal that JD1 comprises three spatially distinct components. Our spectroscopic data indicate that JD1 appears dust-free but is already enriched, $12 + \log {\rm (O/H) } = 7.90^{+0.04}_{-0.05}$. We also find that the Carbon and Neon abundances in JD1 are below the solar abundance ratio. Particularly the Carbon under-abundance is suggestive of recent star formation where Type~II supernovae have already enriched the ISM in Oxygen but intermediate mass stars have not yet enriched the ISM in Carbon. A recent burst of star formation is also revealed by the star formation history derived from NIRCam photometry. Our data do not reveal the presence of a significant amount of old populations, resulting in a factor of $\sim7\times$ smaller stellar mass than previous estimates. Thus, our data support the view that JD1 is a young galaxy.Comment: Accepted for publicatio