2,220 research outputs found
Medication adherence in adolescents and young children with chronic liver disease
Section A is a review of existing empirical research that has investigated variables associated with medication adherence in adolescents and young adults (9-25 years) with a chronic liver disease. Section B describes an empirical project using cross-sectional and longitudinal archival data from a young adult liver service (16-25 years), which investigated whether demographic and clinical variables, mood and illness perceptions were associated with and/or predictive of medication adherence in adolescents and young adults with a range of chronic liver disease diagnoses
WFPC2 Observations of Star Clusters in the Magellanic Clouds: I. The LMC Globular Cluster Hodge 11
We present our analysis of Hubble Space Telescope Wide Field Planetary Camera
2 observations in F555W (broadband V) and F450W (broadband B) of the globular
cluster Hodge 11 in the Large Magellanic Cloud galaxy. The resulting V vs.
(B-V) color-magnitude diagram reaches 2.4 mag below the main-sequence turnoff
(which is at V_TO = 22.65 +- 0.10 mag or M_V^TO = 4.00 +- 0.16 mag). Comparing
the fiducial sequence of Hodge 11 with that of the Galactic globular cluster
M92, we conclude that, within the accuracy of our photometry, the age of Hodge
11 is identical to that of M92 with a relative age-difference uncertainty
ranging from 10% to 21%. Provided that Hodge 11 has always been a part of the
Large Magellanic Cloud and was not stripped from the halo of the Milky Way or
absorbed from a cannibalized dwarf spheroidal galaxy, then the oldest stars in
the Large Magellanic Clouds and the Milky Way appear to have the same age.Comment: 14 pages (LaTeX+aaspp4.sty), 3 tables and 4 figures (Postscript,
gzipped tar file). Postscript version of paper, tables, and full-resolution
figures available at http://www.astro.columbia.edu/~mighell/hodge11.html To
appear in the Astronomical Journa
Photometric evolution of dusty starburst mergers:On the nature of ultra-luminous infrared galaxies
By performing N-body simulations of chemodynamical evolution of galaxies with
dusty starbursts, we investigate photometric evolution of gas-rich major
mergers in order to explore the nature of ultraluminous infrared galaxies
(ULIRGs) with the total infrared luminosity ( for
m) of . Main results are the following three.
(1) Global colors and absolute magnitudes the during dusty starburst of a major
merger do not change with time significantly, because interstellar dust heavily
obscures young starburst populations that could cause rapid evolution of
photometric properties of the merger. (2) Dust extinction of stellar
populations in a galaxy merger with large infrared luminosity (
) is selective in the sense that younger stellar
populations are preferentially obscured by dust than old ones. This is because
younger populations are located in the central region where a larger amount of
dusty interstellar gas can be transferred from the outer gas-rich regions of
the merger. (3) Both and the ratio of to band
luminosity ) increases as the star formation rate increase during
the starburst of the present merger model, resulting in the positive
correlation between and .Comment: 32 pages 25 figures,2001,ApJ,in press. For all 25 PS figures
(including fig25.ps), see
http://newt.phys.unsw.edu.au/~bekki/res.dir/paper.dir/apj06.dir/fig.tar.g
Potential formation sites of super star clusters in ultra-luminous infrared galaxies
Recent observational results on high spatial resolution images of
ultra-luminous infrared galaxies (ULIGs) have revealed very luminous, young,
compact, and heavily obscured super star clusters in their central regions,
suggested to be formed by gas-rich major mergers. By using stellar and gaseous
numerical simulations of galaxy mergers, we firstly demonstrate that the
central regions of ULIGs are the most promising formation sites of super star
clusters owing to the rather high gaseous pressure of the interstellar medium.
Based on simple analytical arguments, we secondly discuss the possibility that
super star clusters in an ULIG can be efficiently transferred into the nuclear
region owing to dynamical friction and consequently merge with one another to
form a single compact stellar nucleus with a seed massive black hole. We thus
suggest that multiple merging between super star clusters formed by nuclear
starbursts in the central regions of ULIGs can result in the formation of
massive black holes.Comment: 12 pages 4 figures, 2001, accepted by ApJ
A principal components approach to parent-to-newborn body composition associations in South India
Background: size at birth is influenced by environmental factors, like maternal nutrition and parity, and by genes. Birth weight is a composite measure, encompassing bone, fat and lean mass. These may have different determinants. The main purpose of this paper was to use anthropometry and principal components analysis (PCA) to describe maternal and newborn body composition, and associations between them, in an Indian population. We also compared maternal and paternal measurements (body mass index (BMI) and height) as predictors of newborn body composition.Methods: weight, height, head and mid-arm circumferences, skinfold thicknesses and external pelvic diameters were measured at 30 ± 2 weeks gestation in 571 pregnant women attending the antenatal clinic of the Holdsworth Memorial Hospital, Mysore, India. Paternal height and weight were also measured. At birth, detailed neonatal anthropometry was performed. Unrotated and varimax rotated PCA was applied to the maternal and neonatal measurements.Results: rotated PCA reduced maternal measurements to 4 independent components (fat, pelvis, height and muscle) and neonatal measurements to 3 components (trunk+head, fat, and leg length). An SD increase in maternal fat was associated with a 0.16 SD increase (?) in neonatal fat (p < 0.001, adjusted for gestation, maternal parity, newborn sex and socio-economic status). Maternal pelvis, height and (for male babies) muscle predicted neonatal trunk+head (? = 0. 09 SD; p = 0.017, ? = 0.12 SD; p = 0.006 and ? = 0.27 SD; p < 0.001). In the mother-baby and father-baby comparison, maternal BMI predicted neonatal fat (? = 0.20 SD; p < 0.001) and neonatal trunk+head (? = 0.15 SD; p = 0.001). Both maternal (? = 0.12 SD; p = 0.002) and paternal height (? = 0.09 SD; p = 0.030) predicted neonatal trunk+head but the associations became weak and statistically non-significant in multivariate analysis. Only paternal height predicted neonatal leg length (? = 0.15 SD; p = 0.003).Conclusion: principal components analysis is a useful method to describe neonatal body composition and its determinants. Newborn adiposity is related to maternal nutritional status and parity, while newborn length is genetically determined. Further research is needed to understand mechanisms linking maternal pelvic size to fetal growth and the determinants and implications of the components (trunk v leg length) of fetal skeletal growt
IREEL: remote experimentation with real protocols and applications over emulated network
This paper presents a novel e-learning platform called IREEL. IREEL is a virtual laboratory allowing students to drive experiments with real Internet applications and end-to-end protocols in the context of networking courses. This platform consists in a remote network emulator offering a set of predefined applications and protocol mechanisms. Experimenters configure and control the emulation and the end-systems behavior in order to perform tests, measurements and observations on protocols or applications operating under controlled specific networking conditions. A set of end-to-end mechanisms, mainly focusing on transport and application level protocols, are currently available. IREEL is scalable and easy to use thanks to an ergonomic web interface
Mortality following a brain tumour diagnosis in patients with multiple sclerosis
Objectives: As brain tumours and their treatment may theoretically have a poorer prognosis in inflammatory central nervous system diseases such as multiple sclerosis (MS), all-cause mortality following a brain tumour diagnosis was compared between patients with and without MS. The potential role of age at tumour diagnosis was also examined. Setting: Hospital inpatients in Sweden with assessment of mortality in hospital or following discharge. Participants: Swedish national registers identified 20 543 patients with an MS diagnosis (1969-2005) and they were matched individually to produce a comparison cohort of 204 163 members of the general population without MS. Everyone with a primary brain tumour diagnosis was selected for this study: 111 with MS and 907 without MS. Primary and secondary outcome measures: 5-year mortality risk following brain tumour diagnosis and age at brain tumour diagnosis. Results: A non-statistically significant lower mortality risk among patients with MS (lower for those with tumours of high-grade and uncertain-grade malignancy and no notable difference for low-grade tumours) produced an unadjusted HR (and 95% CI) of 0.75 (0.56 to 1.02). After adjustment for age at diagnosis, grade of malignancy, sex, region of residence and socioeconomic index, the HR is 0.91 (0.67-1.24). The change in estimate was largely due to adjustment for age at brain tumour diagnosis, as patients with MS were on average 4.7 years younger at brain tumour diagnosis than those in the comparison cohort (p<0.001). Conclusions: Younger age at tumour diagnosis may contribute to mortality reduction in those with highgrade and uncertain-grade brain tumours. Survival following a brain tumour is not worse in patients with MS; even after age at brain tumour diagnosis and grade of malignancy are taken into account
Early exposure to dogs and farm animals and the risk of childhood asthma
IMPORTANCE: The association between early exposure to animals and childhood
asthma is not clear, and previous studies have yielded contradictory results.
OBJECTIVE: To determine whether exposure to dogs and farm animals confers a risk
of asthma.
DESIGN, SETTING AND PARTICIPANTS: In a nationwide cohort study, the
association between early exposure to dogs and farm animals and the risk of
asthma was evaluated and included all children born in Sweden from January 1,
2001, to December 31, 2010 (N = 1,011,051), using registry data on dog and farm
registration, asthma medication, diagnosis, and confounders for parents and their
children. The association was assessed as the odds ratio (OR) for a current
diagnosis of asthma at age 6 years for school-aged children and as the hazard
ratio (HR) for incident asthma at ages 1 to 5 years for preschool-aged children.
Data were analyzed from January 1, 2007, to September 30, 2012.
EXPOSURES: Living
with a dog or farm animal.
MAIN OUTCOMES AND MEASURES: Childhood asthma diagnosis
and medication used.
RESULTS: Of the 1,011,051 children born during the study
period, 376,638 preschool-aged (53,460 [14.2%] exposed to dogs and 1729 [0.5%]
exposed to farm animals) and 276,298 school-aged children (22,629 [8.2%] exposed
to dogs and 958 [0.3%] exposed to farm animals) were included in the analyses. Of
these, 18,799 children (5.0%) in the preschool-aged children's cohort experienced
an asthmatic event before baseline, and 28,511 cases of asthma and 906,071 years
at risk were recorded during follow-up (incidence rate, 3.1 cases per 1000 years
at risk). In the school-aged children's cohort, 11,585 children (4.2%)
experienced an asthmatic event during the seventh year of life. Dog exposure
during the first year of life was associated with a decreased risk of asthma in
school-aged children (OR, 0.87; 95% CI, 0.81-0.93) and in preschool-aged children
3 years or older (HR, 0.90; 95% CI, 0.83-0.99) but not in children younger than 3
years (HR, 1.03; 95% CI, 1.00-1.07). Results were comparable when analyzing only
first-born children. Farm animal exposure was associated with a reduced risk of
asthma in both school-aged children and preschool-aged children (OR, 0.48; 95%
CI, 0.31-0.76, and HR, 0.69; 95% CI, 0.56-0.84), respectively.
CONCLUSIONS AND RELEVANCE: In this study, the data support the hypothesis that exposure to dogs
and farm animals during the first year of life reduces the risk of asthma in
children at age 6 years. This information might be helpful in decision making for
families and physicians on the appropriateness and timing of early animal
exposure.NonePublishe
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