667 research outputs found
Evidence for tidal interaction and merger as the origin of galaxy morphology evolution in compact groups
We present the results of a morphological study based on NIR images of 25
galaxies, with different levels of nuclear activity, in 8 Compact Groups of
Galaxies (CGs). We perform independently two different analysis: a isophotal
study and a study of morphological asymmetries. The results yielded by the two
analysis are highly consistent. For the first time, it is possible to show that
deviations from pure ellipses are produced by inhomogeneous stellar mass
distributions related to galaxy interactions and mergers. We find evidence of
mass asymmetries in 74% of the galaxies in our sample. In 59% of these cases,
the asymmetries come in pairs, and are consistent with tidal effects produced
by the proximity of companion galaxies. The symmetric galaxies are generally
small in size or mass, inactive, and have an early-type morphology. In 20% of
the galaxies we find evidence for cannibalism. In 36% of the early-type
galaxies the color gradient is positive (blue nucleus) or flat. Summing up
these results, as much as 52% of the galaxies in our sample could show evidence
of an on going or past mergers. Our observations suggest that galaxies in CGs
merge more frequently under ``dry'' conditions. The high frequency of
interacting and merging galaxies observed in our study is consistent with the
bias of our sample towards CGs of type B, which represents the most active
phase in the evolution of the groups. In these groups we also find a strong
correlation between asymmetries and nuclear activity in early-type galaxies.
This correlation allows us to identify tidal interactions and mergers as the
cause of galaxy morphology transformation in CGs.[abridge]Comment: 64 pages, 35 figures. Accepted for publication in Ap
Rates of glucose utilization and glucogenesis in rats in the basal state induced by halothane anaesthesia
Dwarf spheroidals in the M81 Group - Metallicity distribution functions and population gradients
We study the dwarf spheroidal galaxies in the nearby M81 group in order to
construct their photometric metallicity distributions and to investigate the
potential presence of population gradients. We select all the dwarf spheroidals
with available Hubble Space Telescope / Advanced Camera for Surveys archival
observations, nine in total. We interpolate isochrones so as to assign a
photometric metallicity to each star within a selection box in the
color-magnitude diagram of each dwarf galaxy. We assume that the dwarf
spheroidals contain mainly an old stellar population. In order to search for
metallicity gradients, we examine the spatial distribution of two stellar
populations that we separate according to their metallicities. As a result, we
present the photometric metallicity distribution functions, the cumulative
histograms and smoothed density maps of the metal-poor and metal-rich stars as
well as of the intermediate-age stars. From our photometric data we find that
all the dwarf spheroidals show a wide range in metallicities, with mean values
that are typical for old and metal-poor systems, with the exception of one
dwarf spheroidal, namely IKN. Some of our dwarf spheroidals exhibit
characteristics of transition-type dwarfs. Compared to the Local Group
transition type dwarfs, the M81 group ones appear to have mean metallicity
values slightly more metal-rich at a given luminosity. All the dwarf
spheroidals considered here appear to exhibit either population gradients or
spatial variations in the centroids of their metal-poor and metal-rich
population. In addition, there are luminous AGB stars detected in all of them
with spatial distributions suggesting that they are well mixed with the old
stars.Comment: 15 pages, 11 figures; A&A accepte
Elevated Expression of Osteopontin May Be Related to Adipose Tissue Macrophage Accumulation and Liver Steatosis in Morbid Obesity
OBJECTIVE—Osteopontin (OPN) plays an important role in the development of insulin resistance and liver complications in dietary murine models. We aimed to determine the expression pattern of OPN and its receptor CD44 in obese patients and mice according to insulin resistance and liver steatosis
Effect of beta-adrenergic stimulation on whole-body and abdominal subcutaneous adipose tissue lipolysis in lean and obese men
AIMS/HYPOTHESIS: Obesity is characterised by increased triacylglycerol storage in adipose tissue. There is in vitro evidence for a blunted beta-adrenergically mediated lipolytic response in abdominal subcutaneous adipose tissue (SAT) of obese individuals and evidence for this at the whole-body level in vivo. We hypothesised that the beta-adrenergically mediated effect on lipolysis in abdominal SAT is also impaired in vivo in obese humans. METHODS: We investigated whole-body and abdominal SAT glycerol metabolism in vivo during 3 h and 6 h [2H5]glycerol infusions. Arterio-venous concentration differences were measured in 13 lean and ten obese men after an overnight fast and during intravenous infusion of the non-selective beta-adrenergic agonist isoprenaline [20 ng (kg fat free mass)(-1) min(-1)]. RESULTS: Lean and obese participants showed comparable fasting glycerol uptake by SAT (9.7+/-3.4 vs 9.3+/-2.5% of total release, p=0.92). Furthermore, obese participants showed an increased whole-body beta-adrenergically mediated lipolytic response versus lean participants. However, their fasting lipolysis was blunted [glycerol rate of appearance: 7.3+/-0.6 vs 13.1+/-0.9 micromol (kg fat mass)(-1) min(-1), p<0.01], as was the beta-adrenergically mediated lipolytic response per unit SAT [Delta total glycerol release: 140+/-71 vs 394+/-112 nmol (100 g tissue)(-1) min(-1), p<0.05] compared with lean participants. Net triacylglycerol flux tended to increase in obese compared with lean participants during beta-adrenergic stimulation [Delta net triacylglycerol flux: 75+/-32 vs 16+/-11 nmol (100 g tissue)(-1) min(-1), p=0.06]. CONCLUSIONS/INTERPRETATION: We demonstrated in vivo that beta-adrenergically mediated lipolytic response is impaired systematically and in abdominal SAT of obese versus lean men. This may be important in the development or maintenance of increased triacylglycerol stores and obesity
Pampering, Well-Being And Women’s Bodies In The Therapeutic Spaces Of The Spa
This is an Author's Accepted Manuscript of an article published in Social and Cultural Geography, 2013, Vol. 14 Issue 1 pp. 41-58 © 2012 copyright Taylor & Francis, available online at: http://www.tandfonline.com/ DOI: 10.1080/14649365.2012.734846This paper develops and extends recent work in geography on therapeutic landscapes and
the body in an examination of pampering practices in the contemporary spa. Drawing on
feminist research on health, gender identity and the body, the paper explores the
importance of escape, relaxation and other strategies to combat stress on the well-being
practices and routines of women. Using original data collected from interviews in two
spas in the South West of England, the paper argues that a visit to the spa is increasingly
being seen as an important part of women’s wider health and bodily maintenance
providing a space for relaxation and withdrawal from responsibilities of the home and
workplace. The pampering treatments reinforce the therapeutic benefits of the spa
creating a sense of luxury and a focus on the self. The paper locates these arguments
within the twin theoretical concerns of the ‘care of the self’ and disciplining the body,
suggesting that any attempts to understand the practices and therapies for maintaining
bodily well-being must incorporate a recognition of their simultaneous role in regulating
the size and shape of women’s bodies
WASP-86b and WASP-102b: super-dense versus bloated planets
We report the discovery of two transiting planetary systems: a super dense, sub-Jupiter mass planet WASP-86b (Mpl = 0.82 ± 0.06 MJ; Rpl = 0.63 ± 0.01 RJ), and a bloated, Saturn-like planet WASP-102b (Mpl = 0.62 ± 0.04 MJ; Rpl = 1.27 ± 0.03 RJ). They orbit their
host star every ∼5.03, and ∼2.71 days, respectively. The planet hosting WASP-86 is a F7 star (Teff = 6330±110 K, [Fe/H] = +0.23 ± 0.14 dex, and age ∼0.8–1 Gyr); WASP-102 is a G0 star (Teff = 5940±140 K, [Fe/H] = −0.09± 0.19 dex, and age ∼1 Gyr). These two systems highlight the diversity of planetary radii over similar masses for giant planets with masses between Saturn and Jupiter. WASP-102b shows a larger than model-predicted radius, indicating that the planet is receiving a strong incident flux which contributes to the inflation of its radius. On the other hand, with a density of ρpl = 3.24± 0.3 ρJ, WASP-86b is the densest gas giant planet among
planets with masses in the range 0.05 Mpl J. With a stellar mass of 1.34 M⊙ and [Fe/H]= +0.23 dex, WASP-86 could host additional massive and dense planets given that its protoplanetary disc is expected to also have been enriched with heavy elements. In order to match WASP-86b’s density, an extrapolation of theoretical models predicts a planet composition of more than 80% in heavy elements (whether confined in a core or mixed in the envelope). This fraction corresponds to a core mass of approximately 210M⊕ for WASP-86b’s mass of Mpl∼260 M⊕. Only planets with masses larger than about 2 MJ have larger densities than that of WASP-86b, making it exceptional in its mass range
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