Distribution and motions of atomic hydrogen in lenticular galaxies. X. The blue SO galaxy NGC 5102

We have mapped the blue gas-rich S0 galaxy NGC 5102 in the 21-cm HI line with a spatial resolution of 34'' x 37'' (DELTAalpha x DELTAdelta) and a velocity resolution of 12 km s-1. Optically NGC 5102 is a peculiar S0 galaxy, in the sense that it has unusually blue colours, and shows evidence for a burst of star formation a few times 10(8) years ago in its nucleus. Also the inner bulge and parts of its disk show signs of low-level star formation activity. It further has a 'supershell' of 1.7 kpc diameter seen in Halpha around its central regions, a unique feature for a lenticular galaxy.The HI distribution has a pronounced central depression of 1.9 kpc radius, and most of the HI is concentrated in a 3.6 kpc wide ring with an average radius of 3.7 kpc (= 0.7 R25), assuming a distance of 4 Mpc for NGC 5102. The maximum azimuthally averaged HI surface density in the ring is 1.4 M. pc-2, comparable to that found in other SO galaxies. The extent of the HI gas is not much larger than the optical de Vaucouleurs' radius (R25) of die galaxy, contrary to what is found in other gas-rich S0's, which often have large outer HI rings at R approximately 2 R25. The HI velocity field is quite regular, showing no evidence for large-scale deviations from circular rotation, and the HI is found to rotate in the plane of the stellar disk. The rotation curve is essentially flat at V(rot) approximately 95 km s-1 out to R = 6 kpc (1.1 R25). Assuming a simple spherical mass model, we find a total mass-to-light ratio M(T)/L(B)0 = 4.3 M./L. within R = 6 kpc.In contrast to other SO galaxies studied in this series of papers, both the HI mass/blue luminosity ratio and the radial HI distribution are similar to those in early-type spirals. The HI may be an old, ''smouldering'', disk or it may have been acquired through capture of a gas-rich smaller galaxy. The recent starburst in the nuclear region, which gave the galaxy its blue colour, may have been caused by partial radial collapse of the gas disk, or by infall of a gas-rich dwarf galaxy.</p

The effect of universal maternal antenatal iron supplementation on neurodevelopment in offspring : a systematic review and meta-analysis

Funding One author (CJ) was funded by the Ministry of Health, Government of Sri Lanka. Availability of data and materials Supporting data can be obtained from the corresponding author.Peer reviewedPublisher PD

Gender difference and effect of pharmacotherapy: findings from a smoking cessation service

Background: Smoking cessation services are available in England to provide assistance to those wishing to quit smoking. Data from one such service were analysed in order to investigate differences in quit rate between males and females prescribed with different treatments. Methods: A logistic regression model was fitted to the data using the binary response of self-reported quit (failed attempt = 0, successful attempt = 1), validated by Carbon Monoxide (CO) monitoring, 4 weeks after commencing programme. Main effects fitted were: client gender; age; region; the type of advisory sessions; and pharmacotherapy, Nicotine Replacement Therapy (NRT) or Varenicline. A second model was fitted including all main effects plus two-way interactions except region. These models were repeated using 12-week self-reported quit as the outcome. Results: At 4 weeks, all main effects were statistically significant, with males more likely (odds ratio and 95 % CI, females v males = 0.88 [0.79–0.97]), older smokers more likely (adjusted odds ratios [OR] and 95 % confidence interval [CI] respectively for groups 20–29, 30–49, 50–69 and 70+ vs 12–19 age group: 1.79 [1.39–2.31], 2.12 [1.68–2.68], 2.30 [1.80–2. 92] and 2.47 [1.81–3.37] and for overall difference between groups, χ 2 (4) = 53.5, p < 0.001) and clients being treated with Varenicline more likely to have successfully quit than those on NRT (adjusted OR and 95 % CI for Varenicline vs NRT = 1.41 [1.21–1.64]). Statistically significant interactions were observed between (i) gender and type of counselling, and (ii) age and type of counselling. Similar results were seen in relation to main effects at 12 weeks except that type of counselling was non-significant. The only significant interaction at this stage was between gender and pharmacotherapy (adjusted OR and 95 % CI for females using Varenicline versus all other groups = 1.43 [1.06–1.94]). Conclusion: Gender and treatment options were identified as predictors of abstinence at both 4 and 12 weeks after quitting smoking. Furthermore, interactions were observed between gender and (i) type of counselling received (ii) pharmacotherapy. In particular, the quit rate in women at 12 weeks was significantly improved in conjunction with Varenicline use. These findings have implications for service delivery

A Chandra Observation of the Nearby Lenticular Galaxy NGC 5102: Where are the X-ray Binaries?

We present results from a 34 ks Chandra/ACIS-S observation of the nearby (d=3.1 Mpc) lenticular galaxy NGC 5102, previously shown to have an unusually low X-ray luminosity. We detect eleven X-ray point sources within the the $D_{25}$ optical boundary of the galaxy (93% of the light), one third to one half of which are likely to be background AGN. One source is coincident with the optical nucleus and may be a low-luminosity AGN. Only two sources with an X-ray luminosity greater than 10$^{37}$ ergs s$^{-1}$ in the 0.5-5.0 keV band were detected, one of which is statistically likely to be a background AGN. We expected to detect 6 such luminous sources if the XRB population scales linearly with optical magnitude of the host galaxy. NGC 5102 has an unusually low number of XRBs. NGC 5102 is unusually blue for its morphological type, and has undergone at least two recent bursts of star formation. We present the results of optical/UV spectral synthesis analysis and demonstrate that a significant fraction ($>$50%) of the stars in this galaxy are comparatively young ($<3\times10^9$ years old). If the lack of X-ray binaries is related to the relative youth of most of the stars, this would support models of LMXB formation and evolution that require wide binaries to shed angular momentum on a timescale of Gyrs. We find that NGC 5102 has an unusually low specific frequency of globular clusters ($S_N\sim$0.4), which could also explain the lack of LMXBs. We also detect diffuse X-ray emission in the central $\sim$1 kpc of the galaxy. This hot gas is most likely a superbubble created by multiple supernovae of massive stars born during the most recent star burst, and is driving the shock into the ISM which was inferred from optical observations.Comment: 33 pages, 7 figures, 6 tables - Accepted for publication in the Astrophysical Journa