18 research outputs found

    Gaia Focused Product Release: Radial velocity time series of long-period variables

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    Context. The third Gaia Data Release (DR3) provided photometric time series of more than 2 million long-period variable (LPV) candidates. Anticipating the publication of full radial-velocity data planned with Data Release 4, this Focused Product Release (FPR) provides radial-velocity time series for a selection of LPV candidates with high-quality observations. Aims. We describe the production and content of the Gaia catalog of LPV radial-velocity time series, and the methods used to compute the variability parameters published as part of the Gaia FPR. Methods. Starting from the DR3 catalog of LPV candidates, we applied several filters to construct a sample of sources with high-quality radial-velocity measurements. We modeled their radial-velocity and photometric time series to derive their periods and amplitudes, and further refined the sample by requiring compatibility between the radial-velocity period and at least one of the G, GBP, or GRP photometric periods. Results. The catalog includes radial-velocity time series and variability parameters for 9614 sources in the magnitude range 6 ≲ G/mag ≲ 14, including a flagged top-quality subsample of 6093 stars whose radial-velocity periods are fully compatible with the values derived from the G, GBP, and GRP photometric time series. The radial-velocity time series contain a mean of 24 measurements per source taken unevenly over a duration of about three years. We identify the great majority of the sources (88%) as genuine LPV candidates, with about half of them showing a pulsation period and the other half displaying a long secondary period. The remaining 12% of the catalog consists of candidate ellipsoidal binaries. Quality checks against radial velocities available in the literature show excellent agreement. We provide some illustrative examples and cautionary remarks. Conclusions. The publication of radial-velocity time series for almost ten thousand LPV candidates constitutes, by far, the largest such database available to date in the literature. The availability of simultaneous photometric measurements gives a unique added value to the Gaia catalog

    Primary progressive versus relapsing-onset multiple sclerosis: presence and prognostic value of /cerebrospinal fluid oligoclonal IgM

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    Abstract BACKGROUND: There is increasing evidence on cerebrospinal fluid (CSF) oligoclonal IgM (OCIgM) predicting a more aggressive disease course in relapsing-remitting Multiple Sclerosis (MS), while there is a scarcity of data for primary progressive MS (PPMS). OBJECTIVE: Our aim was to investigate the presence and possible prognostic value of CSF OCIgM in a group of PPMS and in a group of relapsing-onset MS patients. The possible prognostic role of other clinical and biological factors was also evaluated. METHODS: We calculated the impact of single clinical and biological factors, including CSF OCIgM at onset, on the probability of reaching an Expanded Disability Status Scale of 3 and 4 in 45 PPMS and 104 relapsing-onset MS patients. RESULTS: CSF OCIgM were found in only 13% of PPMS patients and did not influence the time taken to reach an Expanded Disability Status Scale of 3 and 4. Conversely, they were present in 46% of relapsing-onset MS patients and increased the risk of reaching an Expanded Disability Status Scale of 4. Clinical factors with a negative prognostic value in PPMS were age at onset <30 years and onset with pyramidal symptoms, while onset with sensory symptoms in relapsing-onset MS predicted a more favourable course. CONCLUSION: This study confirms that, in relapsing-onset MS patients, the presence of CSF OCIgM at onset predicts a worse disease course. In the cohort of PPMS patients, however, CSF OCIgM were rare, suggesting that heterogeneous pathogenetic mechanisms may be involved in the different MS forms

    Age-related hearing loss in four Italian genetic isolates: an epidemiological study.

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    The objective of this study was to estimate the prevalence of hearing impairment in four genetically isolated Italian villages (Carlantino, Campora, Gioi-Cardile, and Stoccareddo), 1682 subjects were recruited from all the individuals participating in a multidisciplinary study. They underwent otoscopy and pure-tone audiometry and completed a questionnaire. The audiological data show that the percentage of impaired people increases with age and in particular becomes relevant aged over 40. For this reason we decided to compare the PTA values of individuals aged 40 or older. The PTA values of Stoccareddo and Carlantino are statistically different from PTAs of the other villages. Campora and Gioi-Cardile, both located within the Cilento National Park, have similar middle-low frequency PTA values while some differences are present at high frequencies. Using pedigrees it was possible to calculate the heritability of the trait. For Carlantino and Gioi-Cardile the percentage of the phenotype variation attributable to genetic variation is not significant, while for Campora the heritability value is 0.49 (p = 0.01) suggesting that genetic factors may have an important role
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