217 research outputs found

    Evidence of radius inflation in stars approaching the slow-rotator sequence

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    Average stellar radii in open clusters can be estimated from rotation periods and projected rotational velocities under the assumption of random orientation of the spin axis. Such estimates are independent of distance, interstellar absorption, and models, but their validity can be limited by missing data (truncation) or data that only represent upper/lower limits (censoring). We present a new statistical analysis method to estimate average stellar radii in the presence of censoring and truncation. We use theoretical distribution functions of the projected stellar radius Rsin⁑iR \sin i to define a likelihood function in the presence of censoring and truncation. Average stellar radii in magnitude bins are then obtained by a maximum likelihood parametric estimation procedure. This method is capable of recovering the average stellar radius within a few percent with as few as β‰ˆ\approx 10 measurements. Here it is applied for the first time to the dataset available for the Pleiades. We find an agreement better than β‰ˆ\approx 10 percent between the observed RR vs MKM_K relationship and current standard stellar models for 1.2 β‰₯M/MβŠ™β‰₯\ge M/M_{\odot} \ge 0.85 with no evident bias. Evidence of a systematic deviation at 2Οƒ2\sigma level are found for stars with 0.8 β‰₯M/MβŠ™β‰₯\ge M/M_{\odot} \ge 0.6 approaching the slow-rotator sequence. Fast-rotators (PP < 2 d) agree with standard models within 15 percent with no systematic deviations in the whole 1.2 β‰₯M/MβŠ™β‰₯\ge M/M_{\odot} \ge 0.5 range. The evidence found of a possible radius inflation just below the lower mass limit of the slow-rotator sequence indicates a possible connection with the transition from the fast to the slow-rotator sequence.Comment: Accepted by Astronomy and Astrophysics, 11 pages, 6 figure

    Evidence of New Magnetic Transitions in Late-Type Dwarfs from Gaia DR2

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    The second Gaia data release contains the identification of 147 535 low-mass (≀1.4MβŠ™\le 1.4 M_{\odot}) rotational modulation variable candidates on (or close to) the main sequence, together with their rotation period and modulation amplitude. The richness, the period and amplitude range, and the photometric precision of this sample make it possible to unveil, for the first time, signatures of different surface inhomogeneity regimes in the amplitude-period density diagram. The modulation amplitude distribution shows a clear bimodality, with an evident gap at periods P≀2P \le 2 d. The low amplitude branch, in turn, shows a period bimodality with a main clustering at periods Pβ‰ˆP \approx 5 - 10 d and a secondary clustering of ultra-fast rotators at P≀0.5P \le 0.5 d. The amplitude-period multimodality is correlated with the position in the period-absolute magnitude (or period-color) diagram, with the low- and high-amplitude stars occupying different preferential locations. Here we argue that such a multimodality represents a further evidence of the existence of different regimes of surface inhomogeneities in young and middle-age low-mass stars and we lay out possible scenarios for their evolution, which manifestly include rapid transitions from one regime to another. In particular, the data indicate that stars spinning up close to break-up velocity undergo a very rapid change in their surface inhomogeneities configuration, which is revealed here for the first time. The multimodality can be exploited to identify field stars of age ∼\sim 100 -- 600 Myr belonging to the slow-rotator low-amplitude sequence, for which age can be estimated from the rotation period via gyrochronology relationships.Comment: 15 pages, 6 figures, Accepted by Ap

    Clinical, epidemiological and virological features of acute hepatitis B in Italy

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    Purpose To evaluate the association of hepatitis B virus (HBV) genotypes, basal core promoter (BCP)/precore (PC) and S gene mutations with the clinical-epidemiological characteristics of acute hepatitis B (AHB) in Italy. Methods During July 2005–January 2007, 103 symptomatic AHB patients were enrolled and prospectively followed up at 15 national hospitals. HBV genotypes, BCP/ PC and S gene variants were determined by nested-PCR and direct sequence analysis. Results Genotype D, A and F were detected in 49, 45 and 6 % of patients, respectively. BCP, PC, and BCP plus PC variants were found in 3.1, 11.3 and 7.2 % of patients, respectively. At enrollment, 68.3 % of patients were hepatitis B e antigen (HBeAg)-positive and 31.7 % HBeAg-negative. BCP/PC mutations were more common in HBeAg-negative than in HBeAg-positive patients (p < 0.0001). Compared to genotype D patients, those harboring non-D genotypes were more frequently males (p = 0.023), HBeAg-positive (p < 0.001), had higher bilirubin (p = 0.014) and viremia (p = 0.034) levels and less frequently carried BCP/PC mutations (p < 0.001). Non-D genotype patients more often were from Central Italy (p = 0.001) and reported risky sexual exposure (p = 0.021). Two patients had received vaccination before AHB: one harbored genotype F; the other showed a S gene mutation. Four patients developed fulminant AHB; mutations were found in 2 of 3 patients who underwent BCP/ PC sequencing. After a 6-month follow-up, only 2 (2.8 %) patients developed persistent infection. Conclusion AHB by non-D genotypes is increasing in Italy and is associated with risky sexual exposure. The ability of some genotypes to cause persistent and/or severe infection in Italy warrants larger studies for clarificatio

    Gender influence on professional satisfaction and gender issue perception among young oncologists. A survey of the Young Oncologists Working Group of the Italian Association of Medical Oncology (AIOM)

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    Background: The professional gender gap is increasingly recognised in oncology. We explored gender issues perception and gender influence on professional satisfaction/gratification among young Italian oncologists. Methods: Italian oncologists aged 6440 years and members of the Italian Association of Medical Oncology were invited to participate in an online survey addressing workload/burnout, satisfaction in professional abilities and relations, relevant factors for professional gratification, and gender barriers. \u3c72 test for general association or \u3c72 test for trend was used to analyse the data. Results: 201 young oncologists participated in the survey: 67% female, 71% aged 30-40 years, 41% still in training and 82% without children. Women and men were equally poorly satisfied by the relations with people occupying superior hierarchical positions. There was heterogeneity between women and men in current (p=0.011) and expected future (p=0.007) satisfaction in professional abilities: women were more satisfied by current empathy and relations with colleagues and were more confident in their future managerial and team leader skills. The most important elements for professional gratification indicated by all participants were, in general, work-life balance (36%) and intellectual stimulation/research (32%); specifically for women, work-life balance (48%) and intellectual stimulation/research (20%); and specifically for men, career (29%) and social prestige/recognition (26%). Heterogeneity within the same gender emerged. For example, the elements indicated by men as the most important were intellectual stimulation/research (39%) and work-life balance (21%) in general, versus social prestige/recognition (24%) and career (24%), respectively, specifically for men (p<0.0001). More women versus men perceived gender issue as an actual problem (60% vs 38%, p=0.03); men underestimated gender barriers to women's career (p=0.011). Conclusions: Satisfaction in professional abilities varied by gender. Work-life balance is important for both women and men. Stereotypes about gender issues may be present. Gender issue is an actual problem for young oncologists, mostly perceived by women

    An expert consensus on the recommendations for the use of biomarkers in Fabry disease

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    Fabry disease is an X-linked lysosomal storage disorder caused by the accumulation of glycosphingolipids in various tissues and body fluids, leading to progressive organ damage and life-threatening complications. Phenotypic classification is based on disease progression and severity and can be used to predict outcomes. Patients with a classic Fabry phenotype have little to no residual Ξ±-Gal A activity and have widespread organ involvement, whereas patients with a later-onset phenotype have residual Ξ±-Gal A activity and disease progression can be limited to a single organ, often the heart. Diagnosis and monitoring of patients with Fabry disease should therefore be individualized, and biomarkers are available to support with this. Disease-specific biomarkers are useful in the diagnosis of Fabry disease; non-disease-specific biomarkers may be useful to assess organ damage. For most biomarkers it can be challenging to prove they translate to differences in the risk of clinical events associated with Fabry disease. Therefore, careful monitoring of treatment outcomes and collection of prospective data in patients are needed. As we deepen our understanding of Fabry disease, it is important to regularly re-evaluate and appraise published evidence relating to biomarkers. In this article, we present the results of a literature review of evidence published between February 2017 and July 2020 on the impact of disease-specific treatment on biomarkers and provide an expert consensus on clinical recommendations for the use of those biomarkers

    ИндСкс стабилизации Π€Π°Π±Ρ€ΠΈ (FASTEX): ΠΈΠ½Π½ΠΎΠ²Π°Ρ†ΠΈΠΎΠ½Π½Ρ‹ΠΉ инструмСнт для ΠΎΡ†Π΅Π½ΠΊΠΈ клиничСской стабилизации ΠΏΡ€ΠΈ Π±ΠΎΠ»Π΅Π·Π½ΠΈ Π€Π°Π±Ρ€ΠΈ

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    На сСгодняшний дСнь ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Ρ‹ 2 систСмы количСствСнной ΠΎΡ†Π΅Π½ΠΊΠΈ Π±Ρ€Π΅ΠΌΠ΅Π½ΠΈ Π³Π»ΠΈΠΊΠΎΠ³Π΅Π½ΠΎΠ·Π° с Π΄Π΅Ρ„ΠΈΡ†ΠΈΡ‚ΠΎΠΌ Ξ±-Π³Π°Π»Π°ΠΊΡ‚ΠΎΠ·ΠΈΠ΄Π°Π·Ρ‹: индСкс ΠΎΡ†Π΅Π½ΠΊΠΈ стСпСни тяТСсти ΠœΠ°ΠΉΠ½Ρ†Π° (MSSI) ΠΈ систСма балльной ΠΎΡ†Π΅Π½ΠΊΠΈ тяТСсти Π±ΠΎΠ»Π΅Π·Π½ΠΈ Π€Π°Π±Ρ€ΠΈ (DS3). Π‘Π΄Π΅Π»Π°Π½Π° ΠΏΠΎΠΏΡ‹Ρ‚ΠΊΠ° Ρ€Π°Π·Ρ€Π°Π±ΠΎΡ‚Π°Ρ‚ΡŒ Π΄ΠΈΠ½Π°ΠΌΠΈΡ‡Π΅ΡΠΊΡƒΡŽ ΠΌΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΡ‡Π΅ΡΠΊΡƒΡŽ модСль FASTEX (ΠΎΡ‚ Π°Π½Π³Π». FAbry STabilization indEX, индСкс стабилизации Π€Π°Π±Ρ€ΠΈ) для ΠΎΡ†Π΅Π½ΠΊΠΈ клиничСской ΡΡ‚Π°Π±ΠΈΠ»ΡŒΠ½ΠΎΡΡ‚ΠΈ состояния. ΠœΡƒΠ»ΡŒΡ‚ΠΈΠ΄ΠΈΡΡ†ΠΈΠΏΠ»ΠΈΠ½Π°Ρ€Π½Π°Ρ Π³Ρ€ΡƒΠΏΠΏΠ° экспСртов ΠΏΠΎ Π±ΠΎΠ»Π΅Π·Π½ΠΈ Π€Π°Π±Ρ€ΠΈ Π²ΠΏΠ΅Ρ€Π²Ρ‹Π΅ ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠΈΠ»Π° Π½ΠΎΠ²ΡƒΡŽ ΡˆΠΊΠ°Π»Ρƒ ΠΎΡ†Π΅Π½ΠΊΠΈ тяТСсти заболСвания ΠΏΠΎ ΠΏΡ€Π΅Π΄Π²Π°Ρ€ΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠΉ ΠΎΡ†Π΅Π½ΠΊΠ΅ (ΠΎΡ‚ Π°Π½Π³Π». raw score, RS), ΠΎΡΠ½ΠΎΠ²Π°Π½Π½ΡƒΡŽ Π½Π° 3 Π΄ΠΎΠΌΠ΅Π½Π°Ρ… (Π΄ΠΎΠΌΠ΅Π½ Π½Π΅Ρ€Π²Π½ΠΎΠΉ систСмы (боль, цСрСброваскулярныС события), ΠΏΠΎΡ‡Π΅Ρ‡Π½Ρ‹ΠΉ Π΄ΠΎΠΌΠ΅Π½ (протСинурия, ΡΠΊΠΎΡ€ΠΎΡΡ‚ΡŒ ΠΊΠ»ΡƒΠ±ΠΎΡ‡ΠΊΠΎΠ²ΠΎΠΉ Ρ„ΠΈΠ»ΡŒΡ‚Ρ€Π°Ρ†ΠΈΠΈ), сСрдСчный Π΄ΠΎΠΌΠ΅Π½ (ΠΏΠ°Ρ€Π°ΠΌΠ΅Ρ‚Ρ€Ρ‹ эхокардиографии, элСктрокардиографии ΠΈ ΡΡ‚Π΅ΠΏΠ΅Π½ΡŒ сСрдСчной нСдостаточности ΠΏΠΎ классификации Нью-Йоркской кардиологичСской ассоциации)) с нСбольшим числом ΠΏΡƒΠ½ΠΊΡ‚ΠΎΠ² Π² ΠΊΠ°ΠΆΠ΄ΠΎΠΌ ΠΈΠ· Π½ΠΈΡ… ΠΈ ΠΎΡ†Π΅Π½ΠΊΠΎΠΉ клиничСской ΡΡ‚Π°Π±ΠΈΠ»ΡŒΠ½ΠΎΡΡ‚ΠΈ Π²ΠΎ Π²Ρ€Π΅ΠΌΠ΅Π½ΠΈ. RS протСстирована Π½Π° 28 ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚Π°Ρ… (15 ΠΌΡƒΠΆΡ‡ΠΈΠ½ ΠΈ 13 ΠΆΠ΅Π½Ρ‰ΠΈΠ½) с классичСской Ρ„ΠΎΡ€ΠΌΠΎΠΉ Π±ΠΎΠ»Π΅Π·Π½ΠΈ Π€Π°Π±Ρ€ΠΈ. ΠŸΠΎΠ»ΡƒΡ‡Π΅Π½Π° сильная коррСляционная связь ΠΏΡ€Π΅Π΄Π»ΠΎΠΆΠ΅Π½Π½ΠΎΠΉ ΠΎΡ†Π΅Π½ΠΊΠΈ RS ΠΈ взвСшСнной ΠΎΡ†Π΅Π½ΠΊΠΈ (ΠΎΡ‚ Π°Π½Π³Π». weighted score, WS) с DS3 ΠΈ MSSI (r2 = 0,914; 0,949; 0,910 ΠΈ 0,938 соотвСтствСнно). Для уточнСния RS Π±Ρ‹Π»Π° рассчитана WS, выраТаСмая Π² ΠΏΡ€ΠΎΡ†Π΅Π½Ρ‚Π°Ρ…. WS Π±Ρ‹Π»Π° основана Π½Π° ΠΎΡ‚Π½ΠΎΡΠΈΡ‚Π΅Π»ΡŒΠ½ΠΎΠΉ клиничСской значимости ΠΊΠ°ΠΆΠ΄ΠΎΠ³ΠΎ ΠΏΡƒΠ½ΠΊΡ‚Π° Π² ΠΏΡ€Π΅Π΄Π΅Π»Π°Ρ… Π΄ΠΎΠΌΠ΅Π½Π°, ΠΏΡ€ΠΈ этом Π³Ρ€ΡƒΠΏΠΏΠ° экспСртов согласовывала присвоСниС Ρ€Π°Π·Π½ΠΎΠ³ΠΎ вСса клиничСского Π²Ρ€Π΅Π΄Π° ΠΊΠΎΠ½ΠΊΡ€Π΅Ρ‚Π½ΠΎΠΉ систСмС ΠΎΡ€Π³Π°Π½ΠΎΠ². Для опрСдСлСния Π΄ΠΈΠ½Π°ΠΌΠΈΠΊΠΈ тяТСсти заболСвания RS Π±Ρ‹Π»Π° ΠΏΠΎΠ²Ρ‚ΠΎΡ€Π½ΠΎ ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½Π° Ρ‡Π΅Ρ€Π΅Π· 1 Π³ΠΎΠ΄. Π“Ρ€ΡƒΠΏΠΏΠ° экспСртов согласилась с ΠΏΠΎΡ€ΠΎΠ³ΠΎΠ²Ρ‹ΠΌ ΠΎΠ³Ρ€Π°Π½ΠΈΡ‡Π΅Π½ΠΈΠ΅ΠΌ Π² 20 % ΠΎΡ‚ исходного уровня Π² качСствС клиничСской WS для опрСдСлСния клиничСской ΡΡ‚Π°Π±ΠΈΠ»ΡŒΠ½ΠΎΡΡ‚ΠΈ. МодСль FASTEX ΠΏΠΎΠΊΠ°Π·Π°Π»Π° Ρ…ΠΎΡ€ΠΎΡˆΡƒΡŽ ΠΊΠΎΡ€Ρ€Π΅Π»ΡΡ†ΠΈΡŽ с клиничСской ΠΎΡ†Π΅Π½ΠΊΠΎΠΉ ΠΈ клиничСским ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ΠΌ Π½Π° протяТСнии Π²Ρ€Π΅ΠΌΠ΅Π½ΠΈ Ρƒ всСх ΠΏΠ°Ρ†ΠΈΠ΅Π½Ρ‚ΠΎΠ².Β 

    EPURAEA DEUBELI REITTER, 1898, A CONFIRMED SAPROXYLIC SAP BEETLE FOR THE ITALIAN FAUNA (Coleoptera, Nitidulidae)

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    During ecological investigations on saproxylic beetle communities at Monte Baldo (Veneto, Verona province), two specimens of Epuraea deubeli Reitter, 1898 (Coleoptera, Nitidulidae) were recently collected. It is the first known sure record of this species in Italy (previously known from Northern, Eastern, and Central Europe, southwards to Austria, and from Western Siberia)

    VizieR Online Data Catalog: Differential rotation in solar-like stars (Distefano+, 2016)

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    The average rotation period, the parameters Ο‰min Ο‰max, βˆ†Ξ©phot and alphaphot are reported for 111 late-type stars belonging to loose young stellar associations. For each target, the main physical parameters are also reported. The Spectral types, the photometric data and the distances are taken by previous works. The masses, the effective temperatures and the convective turn-over time-scales have been inferred by comparing absolute magnitudes with different sets of theoretical isochrones

    Donation after Circulatory Death in Paediatric Liver Transplantation: Current Status and Future Perspectives in the Machine Perfusion Era

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    Efforts have been made by the transplant community to expand the deceased donor pool in paediatric liver transplantation (LT). The growing experience on donation after circulatory death (DCD) for adult LT has encouraged its use also in children, albeit in selective cases, opening new perspectives for paediatric patients. Even though there has recently been a slight increase in the number of DCD livers transplanted in children, with satisfactory graft and patient outcomes, the use of DCD grafts in paediatric recipients is still controversial due to morbid outcomes associated with DCD grafts. In this context, recent advances in the optimization of donor support by extracorporeal membrane oxygenation and in the graft preservation by liver machine perfusion could find application in order to expand the donor pool in paediatric LT. In the present study we review the current literature on DCD liver grafts transplanted in children and on the use of extracorporeal donor support and liver perfusion machines in paediatrics, with the aim of defining the current status and future perspectives of paediatric LT

    A new bioavailable fenretinide formulation with antiproliferative, antimetabolic, and cytotoxic effects on solid tumors.

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    Fenretinide is a synthetic retinoid characterized by anticancer activity in preclinical models and favorable toxicological profile, but also by a low bioavailability that hindered its clinical efficacy in former clinical trials. We developed a new formulation of fenretinide complexed with 2-hydroxypropyl-beta-cyclodextrin (nanofenretinide) characterized by an increased bioavailability and therapeutic efficacy. Nanofenretinide was active in cell lines derived from multiple solid tumors, in primary spheroid cultures and in xenografts of lung and colorectal cancer, where it inhibited tumor growth independently from the mutational status of tumor cells. A global profiling of pathways activated by nanofenretinide was performed by reverse-phase proteomic arrays and lipid analysis, revealing widespread repression of the mTOR pathway, activation of apoptotic, autophagic and DNA damage signals and massive production of dihydroceramide, a bioactive lipid with pleiotropic effects on several biological processes. In cells that survived nanofenretinide treatment there was a decrease of factors involved in cell cycle progression and an increase in the levels of p16 and phosphorylated p38 MAPK with consequent block in G0 and early G1. The capacity of nanofenretinide to induce cancer cell death and quiescence, together with its elevated bioavailability and broad antitumor activity indicate its potential use in cancer treatment and chemoprevention
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