Optical observations of GRB 060218/SN 2006aj and its host galaxy

The supernova SN 2006aj associated with GRB 060218 is the second-closest GRB-SN observed to date ($z$=0.033) and is the clearest example of a SN associated with a Swift GRB with the earliest optical spectroscopy. Its optical data showed that this is the fastest evolving and among the least luminous GRB-SNe (70% as luminous as SN1998bw). However, its expansion velocity and a comparison with other stripped-envelope SNe suggest that SN2006aj is an intermediate object between Type Ic GRB-SNe and those not accompained by a GRB. High-resolution optical spectroscopy together with SDSS pre-burst observations revealed that the host galaxy of SN2006aj is a low-luminosity, metal-poor star-forming dwarf galaxy.Comment: To appear in conf. proc. of "The Multicoloured Landscape of Compact Objects and their Explosive Progenitors: Theory vs Observations", a conference held in Cefalu, Sicily, June 11-24, 200

The variety of progenitors and afterglows: analysis of three Swift Gamma-Ray Bursts

Gamma-Ray Bursts (GRBs) are brief events in the gamma-ray sky occurring at an average rate of a few per day. While they are on, they outshine every source of gamma-rays in the sky. In fact, they are the brightest electromagnetic explosions in the Universe. Until 11 years ago, they were undetected at any wavelengths other than gamma-rays, which provided poor directional information and hence no direct clues about their site of origin. The current interpretation of how this energy release is produced is that a large amount of energy is released in a short time (seconds or less) by the collapse of the core of a massive star or the merger of two compact stellar objects. This sudden energy liberation results in a fireball expanding at highly relativistic speed, which undergoes internal dissipation leading to gamma-rays, and later develops into a blast wave as it decelerates in the external medium, producing an afterglow which gets progressively weaker. The afterglows provide information about the nature of the GRB progenitor and the physical processes involved in these explosions. In this Thesis three GRBs are discussed where extensive follow-up observations could be performed. Thereby, this Thesis concentrates on the nature of the GRB progenitors, the phenomenology of the afterglows and the host galaxies. In Chapter 1 a brief introduction is given about this research field, followed by an overview of the Thesis. In Chapter 2 a broader summary is presented about the observational status of the field, including the most popular theoretical models. Chapter 3 contains information about the data gathering at various telescopes worldwide. Chapters 4 to 6 are devoted to certain aspects of GRB follow-up observations, namely the search for signatures of the nature of the GRB progenitors, the phenomenology and physical interpretation of the observed afterglow light as well as the nature of the GRB host galaxies. Chapter 7 finally summarizes the main work and results of the Thesis

Interest in hearing loss in geriatric medicine: a survey of members of the <em>Societa' Italiana Geriatria Ospedale e Territorio</em> (SIGOT)

Hearing loss is a common condition in older people. Increasing research has shown that this condition is associated with a higher risk of several health problems. The aim of this survey made among the members of the Societa' Italiana Geriatria Ospedale e Territorio (SIGOT) is to explore how far hearing loss is known in the Italian geriatric community and how to develop a collaboration with other services. A short survey (taking approximately 5 min to complete) was freely available on the SIGOT website and disseminated using social channels. The questionnaire was available during the whole year of 2021. The questionnaire specifically addressed general characteristics/ demographics, general attention to hearing loss problem in older people and relationships with the National Health System, and personal opinions regarding hearing loss. A total of 122 participants (mainly females and aging between 61-70 years) from all Italian Regions were included. The SIGOT members answered that they consider hearing loss as clinically relevant is always important (55.7%). Unfortunately, many members had not audiological centers or specialists available. Moreover, 38.5% of SIGOT members reported that the possibility of correction of hearing loss with prostheses or cochlear implants in older people is very good for older patients and that in 87.7% a significant improvement in quality of life was observed. The interest in hearing loss problems in older people perceived by the SIGOT members is elevated, but some barriers, particularly in the availability of other specialists and in the services given by National Health System are still very limited

Array-Comparative Genomic Hybridization Analysis in Fetuses with Major Congenital Malformations Reveals that 24% of Cases Have Pathogenic Deletions/Duplications

Karyotyping and aCGH are routinely used to identify genetic determinants of major congenital malformations (MCMs) in fetal deaths or terminations of pregnancy after prenatal diagnosis. Pathogenic rearrangements are found with a variable rate of 9-39% for aCGH. We collected 33 fetuses, 9 with a single MCM and 24 with MCMs involving 2-4 organ systems. aCGH revealed copy number variants in 14 out of 33 cases (42%). Eight were classified as pathogenic which account for a detection rate of 24% (8/33) considering fetuses with 1 or more MCMs and 33% (8/24) taking into account fetuses with multiple malformations only. Three of the pathogenic variants were known microdeletion syndromes (22q11.21 deletion, central chromosome 22q11.21 deletion, and TAR syndrome) and 5 were large rearrangements, adding up to >11 Mb per subject and comprising strong phenotype-related genes. One of those was a de novo complex rearrangement, and the remaining 4 duplications and 2 deletions were 130-900 kb in size, containing 1-7 genes, and were classified as variants of unknown clinical significance. Our study confirms aCGH as a powerful technique to ascertain the genetic etiology of fetal major congenital malformations

The Highly Energetic Expansion of SN2010bh Associated with GRB 100316D

We present the spectroscopic and photometric evolution of the nearby (z = 0.059) spectroscopically confirmed type Ic supernova, SN 2010bh, associated with the soft, long-duration gamma-ray burst (X-ray flash) GRB 100316D. Intensive follow-up observations of SN 2010bh were performed at the ESO Very Large Telescope (VLT) using the X-shooter and FORS2 instruments. Owing to the detailed temporal coverage and the extended wavelength range (3000--24800 A), we obtained an unprecedentedly rich spectral sequence among the hypernovae, making SN 2010bh one of the best studied representatives of this SN class. We find that SN 2010bh has a more rapid rise to maximum brightness (8.0 +/- 1.0 rest-frame days) and a fainter absolute peak luminosity (L_bol~3e42 erg/s) than previously observed SN events associated with GRBs. Our estimate of the ejected (56)Ni mass is 0.12 +/- 0.02 Msun. From the broad spectral features we measure expansion velocities up to 47,000 km/s, higher than those of SNe 1998bw (GRB 980425) and 2006aj (GRB 060218). Helium absorption lines He I lambda5876 and He I 1.083 microm, blueshifted by ~20,000--30,000 km/s and ~28,000--38,000 km/s, respectively, may be present in the optical spectra. However, the lack of coverage of the He I 2.058 microm line prevents us from confirming such identifications. The nebular spectrum, taken at ~186 days after the explosion, shows a broad but faint [O I] emission at 6340 A. The light-curve shape and photospheric expansion velocities of SN 2010bh suggest that we witnessed a highly energetic explosion with a small ejected mass (E_k ~ 1e52 erg and M_ej ~ 3 Msun). The observed properties of SN 2010bh further extend the heterogeneity of the class of GRB supernovae.Comment: 37 pages and 12 figures (one-column pre-print format), accepted for publication in Ap

Large cryptic genomic rearrangements with apparently normal karyotypes detected by array-CGH.

Background: Conventional karyotyping (550 bands resolution) is able to identify chromosomal aberrations >5-10 Mb, which represent a known cause of intellectual disability/developmental delay (ID/DD) and/or multiple congenital anomalies (MCA). Array-Comparative Genomic Hybridization (array-CGH) has increased the diagnostic yield of 15-20%. Results: In a cohort of 700 ID/DD cases with or without MCA, including 15 prenatal diagnoses, we identified a subgroup of seven patients with a normal karyotype and a large complex rearrangement detected by array-CGH (at least 6, and up to 18 Mb). FISH analysis could be performed on six cases and showed that rearrangements were translocation derivatives, indistinguishable from a normal karyotype as they involved a similar band pattern and size. Five were inherited from a parent with a balanced translocation, whereas two were apparently de novo. Genes spanning the rearrangements could be associated with some phenotypic features in three cases (case 3: DOCK8; case 4: GATA3, AKR1C4; case 6: AS/PWS deletion, CHRNA7), and in two, likely disease genes were present (case 5: NR2F2, TP63, IGF1R; case 7: CDON). Three of our cases were prenatal diagnoses with an apparently normal karyotype. Conclusions: Large complex rearrangements of up to 18 Mb, involving chromosomal regions with similar size and band appearance may be overlooked by conventional karyotyping. Array-CGH allows a precise chromosomal diagnosis and recurrence risk definition, further confirming this analysis as a first tier approach to clarify molecular bases of ID/DD and/or MCA. In prenatal tests, array-CGH is confirmed as an important tool to avoid false negative results due to karyotype intrinsic limit of detection