1,298 research outputs found
The supernova impostor PSN J09132750+7627410 and its progenitor
We report the results of our follow-up campaign of the supernova impostor PSN
J09132750+7627410, based on optical data covering . From the
beginning, the transient shows prominent narrow Balmer lines with P-Cygni
profiles, with a blue-shifted absorption component becoming more prominent with
time. Along the of the spectroscopic monitoring, broad
components are never detected in the hydrogen lines, suggesting that these
features are produced in slowly expanding material. The transient reaches an
absolute magnitude at maximum, a typical
luminosity for supernova impostors. Amateur astronomers provided
of archival observations of the host galaxy, NGC 2748. The
detection of the quiescent progenitor star in archival images obtained with the
Hubble Space Telescope suggests it to be an \msun white-yellow
supergiant.Comment: 7 pages, 4 figures, supplemental material available in the source
file. Accepted for publication on Astrophysical Journal Letter
Neonatal screening for congenital hypothyroidism in an Italian Centre: a 5-years real-life retrospective study
Introduction: Congenital hypothyroidism is an endocrine disease with a significant incidence in the general population (1:2000–1:3000 newborns in Italy) and a different geographical distribution, partially explained by endemic iodine deficiency, genetic traits and autoimmune thyroid diseases. Objectives: Aims of this study are: to evaluate the incidence of positive neonatal blood spot screening for CH in western Sicily, identified by the screening centre of the Children Hospital “G. Di Cristina”, ARNAS, Palermo; to evaluate the impact of a lower TSH cutoff in the neonatal blood spot screening for CH. Materials and methods: The TSH threshold of the neonatal screening was established as ≥6 mU/L of whole blood. We analysed the screening centre data in the period January 2013–April 2018, for a total number of 85.373 babies (45.7% males; 54.3% females). Results: 4.082 Babies (4.8%) required a second screening. Among these, 372 (0.44%) were out of range. The diagnosis of congenital hypothyroidism (CH) was confirmed in 182 babies (0.21%). 77/372 newborns (20.7%) with confirmed high TSH levels showed whole blood TSH levels ≥6 - < 7 mU/L. In synthesis, 48.9% of the out of range re-testing had a confirmed diagnosis of CH. Conclusion: The reduction of TSH cutoff to 6 mU/L allowed to identify 77/372 neonates (20.7%) with confirmed out of range TSH, otherwise not recruited by the previously employed TSH cutoff
Sex steroids, carcinogenesis, and cancer progression
The relationship between sex steroids and cancer has been studied for more than a century. Using an original intact cell analysis, we investigated sex steroid metabolism in a panel of human cancer cell lines, either hormone responsive or unresponsive, originating from human breast, endometrium, and prostate. We found that highly divergent patterns of steroid metabolism exist and that the catalytic preference (predominantly reductive or oxidative) is strictly associated with the steroid receptor status of cells. We explored intra-tissue concentrations and profiles of estrogens in a set of human breast tumors as compared to normal mammary tissues, also in relation to their estrogen receptor status. In particular, we showed that, with hydroxyestrogens representing the majority of all tissue estrogens, concentrations of individual metabolites, as well as their ratios, significantly differ when comparing normal tissue with cancer tissues or when they are related to the overall survival of cancer patients. © 2004 New York Academy of Sciences
Sigurðar saga fóts (The Saga of Sigurðr Foot): A Translation
This is the first English translation of the short Icelandic romance Sigurðar saga fóts, with an introduction presenting the evidence for its dating and immediate literary context. Like most Icelandic romances, Sigurðar saga is a bridal-quest story; the support of a foster-brother is key to the hero winning the bride; and the foster-brothers start out as opponents before recognising their mutual excellence and swearing foster-brotherhood. Uniquely, however, the men who become foster-brothers begin by competing for the same bride (Signý): the eponymous Sigurðr fótr wins Signý only because Ásmundr gives her to him in exchange for foster-brotherhood. Ásmundr’s decision can be read as demonstrating with unusual starkness the superior importance in much Icelandic romance of homosocial relationships over heterosexual ones, giving the saga a certain paradigmatic status. Translating the saga in an open-access forum and reconstructing its literary context will, we hope, encourage further analyses
Sigurðar saga fóts (The Saga of Sigurðr Foot): A Translation
This is the first English translation of the short Icelandic romance Sigurðar saga fóts, with an introduction presenting the evidence for its dating and immediate literary context. Like most Icelandic romances, Sigurðar saga is a bridal-quest story; the support of a foster-brother is key to the hero winning the bride; and the foster-brothers start out as opponents before recognising their mutual excellence and swearing foster-brotherhood. Uniquely, however, the men who become foster-brothers begin by competing for the same bride (Signý): the eponymous Sigurðr fótr wins Signý only because Ásmundr gives her to him in exchange for foster-brotherhood. Ásmundr’s decision can be read as demonstrating with unusual starkness the superior importance in much Icelandic romance of homosocial relationships over heterosexual ones, giving the saga a certain paradigmatic status. Translating the saga in an open-access forum and reconstructing its literary context will, we hope, encourage further analyses
Androgen metabolism and inhibition of interleukin-1 synthesis in primary cultured human synovial macrophages
The presence of androgen receptors on synovial macrophages in human normal and rheumatoid synovial tissues has been described previously. It is now reported that primary cultured human macrophages obtained from normal and rheumatoid synovia express functional androgen receptors. We have investigated the capacity of cultured macrophages to metabolize androgens and have found that these cells were capable of metabolizing testosterone to the bioactive metabolite dihydrotestosterone. Therefore, macrophages contain the key enzymes of steroidogenesis, in particular the 5α-treductase. Furthermore, interleukin-1β production by primary cultured rheumatoid macrophages was analysed, following exposure to physiological concentrations of testosterone (10−8 M). A significant decrease of IL-1β levels in conditioned media after 24 h (p < 0.05) was observed. It is concluded that androgens may act directly on human macrophages and may interfere with some of their functions via receptor-dependent mechanisms
Pathogenesis, diagnosis and treatment of Rasmussen encephalitis: A European consensus statement
Rasmussen encephalitis (RE) is a rare but severe immune-mediated brain disorder leading to unilateral hemispheric atrophy, associated progressive neurological dysfunction and intractable seizures. Recent data on the pathogenesis of the disease, its clinical and paraclinical presentation, and therapeutic approaches are summarized. Based on these data, we propose formal diagnostic criteria and a therapeutic pathway for the management of RE patient
Ternary Quarter Wavelength Coatings for Gravitational Wave Detector Mirrors: Design Optimization via Exhaustive Search
Multimaterial optical coatings are a promising viable option to meet the
challenging requirements (in terms of transmittance, absorbance and thermal
noise) of next generation gravitational wave detector mirrors. In this paper we
focus on ternary coatings consisting of quarter-wavelength thick layers, where
a third material (H') is added to the two presently in use, namely Silica (L)
and Titania-doped Tantala (H), featuring higher dielectric contrast (against
Silica), and lower thermal noise (compared to Titania-doped Tantala), but
higher optical losses. We seek the optimal material sequences, featuring
minimal thermal (Brownian) noise under prescribed transmittance and absorbance
constraints, by exhaustive simulation over all possible configurations, for
different values (in a meaningful range) of the optical density and extinction
coefficient of the third material. In all cases studied, the optimal designs
consist of a stack of (H'|L) doublets topped by a stack of (H|L) doublets,
confirming previous heuristic assumptions, and the achievable coating noise
power spectral density reduction factor is \sim 0.5. The robustness of the
found optimal designs against layer thickness deposition errors and
uncertainties and/or fluctuations in the optical losses of the third material
is also investigated. Possible margins for further thermal noise reduction by
layer thickness optimization, and strategies to implement it, are discussed.Comment: (twocolum style) 13 pages, 8 figures, 4 table (updated version 5)
Appearing on Physical Review Researc
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