Most radiative transfer models assume that dust in spiral galaxies is distributed exponentially. In this paper our goal is to verify this assumption by analysing the two-dimensional large-scale ...distribution of dust in galaxies from the DustPedia sample. For this purpose, we have made use of Herschel imaging in five bands, from 100 to 500 μm, in which the cold dust constituent is primarily traced and makes up the bulk of the dust mass in spiral galaxies. For a subsample of 320 disc galaxies, we successfully performed a simultaneous fitting with a single Sérsic model of the Herschel images in all five bands using the multi-band modelling code GALFITM. We report that the Sérsic index n, which characterises the shape of the Sérsic profile, lies systematically below 1 in all Herschel bands and is almost constant with wavelength. The average value at 250 μm is 0.67 ± 0.37 (187 galaxies are fitted with n250 ≤ 0.75, 87 galaxies have 0.75 < n250 ≤ 1.25, and 46 – with n250 > 1.25). Most observed profiles exhibit a depletion in the inner region (at r < 0.3−0.4 of the optical radius r25) and are more or less exponential in the outer part. We also find breaks in the dust emission profiles at longer distances (0.5−0.6) r25 which are associated with the breaks in the optical and near-infrared. We assumed that the observed deficit of dust emission in the inner galaxy region is related to the depression in the radial profile of the HI surface density in the same region because the atomic gas reaches high enough surface densities there to be transformed into molecular gas. If a galaxy has a triggered star formation in the inner region (for example, because of a strong bar instability, which transfers the gas inwards to the centre, or a pseudobulge formation), no depletion or even an excess of dust emission in the centre is observed.
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Scaling relations between supermassive black hole mass, M
BH, and host galaxy properties are a powerful instrument for studying their co-evolution. A complete picture involving all of the black hole ...scaling relations, in which each relation is consistent with the others, is necessary to fully understand the black hole-galaxy connection. The relation between M
BH and the central light concentration of the surrounding bulge, quantified by the Sérsic index n, may be one of the simplest and strongest such relations, requiring only uncalibrated galaxy images. We have conducted a census of literature Sérsic index measurements for a sample of 54 local galaxies with directly measured M
BH values. We find a clear M
BH-n relation, despite an appreciable level of scatter due to the heterogeneity of the data. Given the current M
BH-L
sph and the L
sph-n relations, we have additionally derived the expected
M
BH-n relations, which are marginally consistent at the 2σ level with the observed relations. Elliptical galaxies and the bulges of disc galaxies are each expected to follow two distinct bent
M
BH-n relations due to the Sérsic/core-Sérsic divide. For the same central light concentration, we predict that M
BH in the Sérsic bulges of disc galaxies are an order magnitude higher than in Sérsic elliptical galaxies if they follow the same M
BH-L
sph relation.
Purpose
The purpose of this study was to evaluate the effects of 16 weeks combined aerobic and resistance training, twice a week, on the physical performance in women treated for gynecological ...cancer.
Methods
Sixty women (56.9 ± 13.3 years) who had completed curative treatment for gynecological cancer were divided into two groups: a physical training group (PT) (
n
= 29) or a control group (C) (
n
= 31). The PT group performed two sessions of combined aerobic and resistance training weekly for 16 weeks. Peak oxygen consumption (V̇O
2peak
) and one repetition maximum (1RM) of leg press, leg extension, and chest press were measured before group assignment, after 16 weeks and at the 1-year follow-up.
Results
A significant increase in V̇O
2peak
(ml min
−1
kg
−1
) (29.7 ± 8.0 vs. 31.3 ± 8.3,
p
= .009), leg press (kg) (113.0 ± 27.3 vs. 116.7 ± 29.2,
p
= .047), leg extension (kg) (44.2 ± 10.1 vs. 48.0 ± 10.6,
p
< .001), and chest press (kg) (24.5 ± 7.5 vs. 26.9 ± 8.2,
p
= .001) was seen in the PT group from pre- to post-measurement. The PT group maintained the improved aerobic condition and muscle strength 1 year after the training intervention. In the C group, there were no significant differences between pre- and post-measurements, but a significant decrease (28.2 ± 7.5 vs. 27.0 ± 7.3,
p
= .040) in the V̇O
2peak
from post to 1-year follow-up measurements.
Conclusions
Combined aerobic and resistance training twice a week in 16 weeks improves V̇O
2peak
and maximal strength in women treated for gynecological cancer. The training effects were sustained after 1 year in the PT group.
The European Space Agency has invested heavily in two cornerstones missions: Herschel and Planck. The legacy data from these missions provides an unprecedented opportunity to study cosmic dust in ...galaxies so that we can, for example, answer fundamental questions about the origin of the chemical elements, physical processes in the interstellar medium (ISM), its effect on stellar radiation, its relation to star formation and how this relates to the cosmic far-infrared background. In this paper we describe the DustPedia project, which enables us to develop tools and computer models that will help us relate observed cosmic dust emission to its physical properties (chemical composition, size distribution, and temperature), its origins (evolved stars, supernovae, and growth in the ISM), and the processes that destroy it (high-energy collisions and shock heated gas). To carry out this research, we combine the Herschel/Planck data with that from other sources of data, and provide observations at numerous wavelengths ( ≤ 41 ) across the spectral energy distribution, thus creating the DustPedia database. To maximize our spatial resolution and sensitivity to cosmic dust, we limit our analysis to 4231 local galaxies ( v < 3000 km s−1) selected via their near-infrared luminosity (stellar mass). To help us interpret this data, we developed a new physical model for dust (THEMIS), a new Bayesian method of fitting and interpreting spectral energy distributions (HerBIE) and a state-of-the-art Monte Carlo photon-tracing radiative transfer model (SKIRT). In this, the first of the DustPedia papers, we describe the project objectives, data sets used, and provide an insight into the new scientific methods we plan to implement.
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We present a multi-wavelength analysis of the galaxies in nine clusters selected from the WINGS dataset, examining how galaxy structure varies as a function of wavelength and environment using the ...state of the art software
GALAPAGOS-2
. We simultaneously fit single-Sérsic functions on three optical (
u
,
B
and
V
) and two near-infrared (
J
and
K
) bands thus creating a wavelength-dependent model of each galaxy. We measure the magnitudes, effective radius (
R
e
), the Sérsic index (
n
), axis ratio, and position angle in each band. The sample contains 790 cluster members (located close to the cluster centre < 0.64 ×
R
200
) and 254 non-member galaxies that we further separate based on their morphology into ellipticals, lenticulars, and spirals. We find that the Sérsic index of all galaxies inside clusters remains nearly constant with wavelength while
R
e
decreases as wavelength increases for all morphological types. We do not observe a significant variation on
n
and
R
e
as a function of projected local density and distance from the clusters centre. Comparing the
n
and
R
e
of bright cluster galaxies with a subsample of non-member galaxies we find that bright cluster galaxies are more concentrated (display high
n
values) and are more compact (low
R
e
). Moreover, the light profile ( ) and size (ℛ) of bright cluster galaxies does not change as a function of wavelength in the same manner as non-member galaxies.
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We present a multi-wavelength analysis of the galaxies in nine clusters selected from the WINGS dataset, examining how galaxy structure varies as a function of wavelength and environment using the ...state of the art software GALAPAGOS-2. We simultaneously fit single-Sérsic functions on three optical (u, B and V) and two near-infrared (J and K) bands thus creating a wavelength-dependent model of each galaxy. We measure the magnitudes, effective radius (Re), the Sérsic index (n), axis ratio, and position angle in each band. The sample contains 790 cluster members (located close to the cluster centre < 0.64 × R200) and 254 non-member galaxies that we further separate based on their morphology into ellipticals, lenticulars, and spirals. We find that the Sérsic index of all galaxies inside clusters remains nearly constant with wavelength while Re decreases as wavelength increases for all morphological types. We do not observe a significant variation on n and Re as a function of projected local density and distance from the clusters centre. Comparing the n and Re of bright cluster galaxies with a subsample of non-member galaxies we find that bright cluster galaxies are more concentrated (display high n values) and are more compact (low Re). Moreover, the light profile (??) and size (ℛ) of bright cluster galaxies does not change as a function of wavelength in the same manner as non-member galaxies.
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We use a sub-set of the DustPedia galaxy sample (461 galaxies) to investigate the effect the environment has had on galaxies. We consider Virgo cluster and field samples and also assign a density ...contrast parameter to each galaxy, as defined by the local density of SDSS galaxies. We consider their chemical evolution (using MDust/MBaryon and MGas/MBaryon), their specific star formation rate (SFR/MStars), star formation efficiency (SFR/MGas), stars-to-dust mass ratio (MStars/MDust), gas-to-dust mass ratio (MGas/MDust) and the relationship between star formation rate per unit mass of dust and dust temperature (SFR/MDust and TDust). Late type galaxies (later than Sc) in all of the environments can be modelled using simple closed box chemical evolution and a simple star formation history (SFR(t) ∝ t exp−t/τ). For earlier type galaxies the physical mechanisms that give rise to their properties are clearly much more varied and require a more complicated model (mergers, gas in or outflow). However, we find little or no difference in the properties of galaxies of the same morphological type within the cluster, field or with different density contrasts. It appears that it is morphology, how and whenever this is laid down, and consistent internal physical processes that primarily determine the derived properties of galaxies in the DustPedia sample and not processes related to differences in the local environment.
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DustPedia Davies, J. I.; Baes, M.; Bianchi, S. ...
Publications of the Astronomical Society of the Pacific,
04/2017, Volume:
129, Issue:
974
Journal Article
Peer reviewed
The European Space Agency has invested heavily in two cornerstones missions: Herschel and Planck. The legacy data from these missions provides an unprecedented opportunity to study cosmic dust in ...galaxies so that we can, for example, answer fundamental questions about the origin of the chemical elements, physical processes in the interstellar medium (ISM), its effect on stellar radiation, its relation to star formation and how this relates to the cosmic far-infrared background. In this paper we describe the DustPedia project, which enables us to develop tools and computer models that will help us relate observed cosmic dust emission to its physical properties (chemical composition, size distribution, and temperature), its origins (evolved stars, supernovae, and growth in the ISM), and the processes that destroy it (high-energy collisions and shock heated gas). To carry out this research, we combine the Herschel/Planck data with that from other sources of data, and provide observations at numerous wavelengths (⩽41) across the spectral energy distribution, thus creating the DustPedia database. To maximize our spatial resolution and sensitivity to cosmic dust, we limit our analysis to 4231 local galaxies (ν < 3000 km s−1) selected via their near-infrared luminosity (stellar mass). To help us interpret this data, we developed a new physical model for dust (THEMIS), a new Bayesian method of fitting and interpreting spectral energy distributions (HerBIE) and a state-of-the-art Monte Carlo photon-tracing radiative transfer model (SKIRT). In this, the first of the DustPedia papers, we describe the project objectives, data sets used, and provide an insight into the new scientific methods we plan to implement.
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The aim of the present study was to evaluate the prevalence of self‐reported problems (fear, pain, unpleasantness, fainting) of dental and medical injections, and the extent to which such problems ...may lead to avoidance of necessary treatment. The study included a representative sample (n = 1385) of 18‐yr‐old students attending high schools in the county of Hordaland, Norway. Data were collected by use of questionnaires completed in the classrooms. More problems were reported during dental than medical injections. About 17% and 15% of participants reported high fear during their last dental and medical injection, respectively. Fainting had been experienced by 2% during a dental injection and by 7% during a medical injection. Avoidance of treatment when an injection is needed was 6.7% for dental treatment and 5.2% for medical treatment. In multiple regression analyses, fear was the only explanatory factor for the avoidance of dental treatment. It is concluded that self‐reported problems of injections are prevalent in this age group, particularly among girls, and that it may lead to the avoidance of necessary treatment in 5–7% of the adolescent population.
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