5,200 research outputs found
Chronic kidney disease in Nigeria: an evaluation of the spatial accessibility to healthcare for diagnosed cases in Edo State
Chronic kidney disease (CKD) is a growing problem in Nigeria, presenting challenges to the nation’s health and economy. This study evaluates the accessibility to healthcare in Edo State of CKD patients diagnosed between 2006 and 2009. Using cost analysis techniques within a geographical information system, an estimated travel time to the hospital was used to examine the spatial accessibility of diagnosed patients to available CKD healthcare in the state. The results from the study indicated that although there was an annual rise in the number of diagnosed cases, there were no significant changes in the proportion of patients that were diagnosed at the last stage of CKD. However, there were indications that the travel time to the hospital for CKD treatment might be a contributing factor to the number of diagnosed CKD cases. This implies that the current structure for CKD management within the state might not be adequate
The cosmic evolution of radio-AGN feedback to z=1
This paper presents the first measurement of the radio luminosity function of
'jet-mode' (radiatively-inefficient) radio-AGN out to z=1, in order to
investigate the cosmic evolution of radio-AGN feedback. Eight radio source
samples are combined to produce a catalogue of 211 radio-loud AGN with
0.5<z<1.0, which are spectroscopically classified into jet-mode and
radiative-mode (radiatively-efficient) AGN classes. Comparing with large
samples of local radio-AGN from the Sloan Digital Sky Survey, the cosmic
evolution of the radio luminosity function of each radio-AGN class is
independently derived. Radiative-mode radio-AGN show an order of magnitude
increase in space density out to z~1 at all luminosities, consistent with these
AGN being fuelled by cold gas. In contrast, the space density of jet-mode
radio-AGN decreases with increasing redshift at low radio luminosities (L_1.4 <
1e24 W/Hz) but increases at higher radio luminosities. Simple models are
developed to explain the observed evolution. In the best-fitting models, the
characteristic space density of jet-mode AGN declines with redshift in
accordance with the declining space density of massive quiescent galaxies,
which fuel them via cooling of gas in their hot haloes. A time delay of 1.5-2
Gyr may be present between the quenching of star formation and the onset of
jet-mode radio-AGN activity. The behaviour at higher radio luminosities can be
explained either by an increasing characteristic luminosity of jet-mode
radio-AGN activity with redshift (roughly as (1+z) cubed) or if the jet-mode
radio-AGN population also includes some contribution of cold-gas-fuelled
sources seen at a time when their accretion rate was low. Higher redshifts
measurements would distinguish between these possibilities.Comment: Accepted for publication in MNRA
Cosmic downsizing of powerful radio galaxies to low radio luminosities
At bright radio powers ( W/Hz) the space density
of the most powerful sources peaks at higher redshift than that of their weaker
counterparts. This paper establishes whether this luminosity-dependent
evolution persists for sources an order of magnitude fainter than those
previously studied, by measuring the steep--spectrum radio luminosity function
(RLF) across the range W/Hz, out to high
redshift. A grid-based modelling method is used, in which no assumptions are
made about the RLF shape and high-redshift behaviour. The inputs to the model
are the same as in Rigby et al. (2011): redshift distributions from radio
source samples, together with source counts and determinations of the local
luminosity function. However, to improve coverage of the radio power vs.
redshift plane at the lowest radio powers, a new faint radio sample is
introduced. This covers 0.8 sq. deg., in the Subaru/XMM-Newton Deep Field, to a
1.4 GHz flux density limit of Jy, with 99%
redshift completeness. The modelling results show that the previously seen
high-redshift declines in space density persist to
W/Hz. At W/Hz the redshift of the peak space
density increases with luminosity, whilst at lower radio luminosities the
position of the peak remains constant within the uncertainties. This `cosmic
downsizing' behaviour is found to be similar to that seen at optical
wavelengths for quasars, and is interpreted as representing the transition from
radiatively efficient to inefficient accretion modes in the steep-spectrum
population. This conclusion is supported by constructing simple models for the
space density evolution of these two different radio galaxy classes; these are
able to successfully reproduce the observed variation in peak redshift.Comment: 7 pages, 6 figures; accepted for publication in Astronomy &
Astrophysic
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Differences in the Experience of Caregiving Between Spouse and Adult Child Caregivers in Dementia With Lewy Bodies.
Background and objectivesDementia caregiving has been associated with increased burden, depression, grief, a decreased sense of well-being and quality of life, and a weakening of social support. Little is known about the experience of caregiving in Dementia with Lewy Bodies (DLB). The present study examines differences in the caregiving experience of spouse versus adult child caregivers of individuals with DLB.Research design and methodsIn this cross-sectional analytic study of spouses (n = 255) and adult children (n = 160) caregivers of individuals with DLB, participants completed an online survey of burden, grief, depression, well-being, quality of life, and social support.ResultsAdult child caregivers were more likely to care for women (p < .001) and see the care recipient less often (p < .001) than spouses. Adult child caregivers reported lower quality of life (p < .001) and more caregiver burden (p < .009), but also greater social support (p < .001) than spouses. Between group analyses of caregiver type by disease severity demonstrated that spousal caregivers experience greater grief with advancing disease (p = .005), while adult child caregivers increase social support with advancing disease (p < .001).Discussion and implicationsSpouses and adult children experience DLB caregiving differently. This was explained by the younger age of the adult child caregiver, frequency of contact with the care recipient, and differences in the care recipient's characteristics, frequency of neuropsychiatric symptoms, and disease severity. DLB caregiver support for this population should target psychoeducation for complicated neuropsychiatric symptoms in the care recipient. Screening all DLB caregivers for burden, grief, and depression is suggested to identify those that may benefit most from intervention. Spouses specifically may benefit from interventions that target increasing social support, while adult child caregivers may benefit from interventions aimed at mitigating burden and improving quality of life
Effect of plyometric training on swimming block start performance in adolescents
This study aimed to identify the effect of plyometric training (PT), when added to habitual training (HT) regimes, on swim start performance. After the completion of a baseline competitive swim start, 22 adolescent swimmers were randomly assigned to either a PT (n = 11, age: 13.1 ± 1.4 yr, mass: 50.6 ± 12.3 kg, stature: 162.9 ± 11.9 cm) or an HT group (n = 11, age: 12.6 ± 1.9 yr, mass: 43.3 ± 11.6 kg, stature: 157.6 ± 11.9 cm). Over an 8-week preseason period, the HT group continued with their normal training program, whereas the PT group added 2 additional 1-hour plyometric-specific sessions, incorporating prescribed exercises relating to the swimming block start (SBS). After completion of the training intervention, post-training swim start performance was reassessed. For both baseline and post-trials, swim performance was recorded using videography (50Hz Canon MVX460) in the sagital plane of motion. Through the use of Silicon Coach Pro analysis package, data revealed significantly greater change between baseline and post-trials for PT when compared with the HT group for swim performance time to 5.5 m (−0.59 s vs. −0.21 s; p < 0.01) and velocity of take-off to contact (0.19 ms−1 vs. −0.07 ms−1; p < 0.01). Considering the practical importance of a successful swim start to overall performance outcome, the current study has found that inclusion of suitable and safely implemented PT to adolescent performers, in addition to HT routines, can have a positive impact on swim start performance
Cattle breeding in Northern Australia: Revealing how consumers react to new technologies
In Australia, Bos taurus cattle breeds produce high quality meat, superior in taste and tenderness characteristics. Nevertheless, these breeds do not thrive in the Northern Australian environment. Stem cell transplant techniques could improve northern beef cattle breeding programs by facilitating crossbreeding via natural service. Focus groups were used in this study to explore consumer reaction to reproduction technologies and the implications for buying intentions. Findings suggested that consumers may react negatively to unconventional breeding technologies but the degree of this aversion is contingent upon how the technology is described. These findings are relevant for preparation of choice modeling surveys.Non-market valuation, consumers, focus groups, new technologies, beef,
SINFONI Observations of Starclusters in Starburst Galaxies
We have used ESO's new NIR IFS SINFONI during its Science Verification period
to observe the central regions of local starburst galaxies. Being Science
Verification observations, the aim was two-fold: to demonstrate SINFONI's
capabilities while obtaining information on the nature of starclusters in
starburst galaxies. The targets chosen include a number of the brighter
clusters in NGC1808 and NGC253. Here we present first results.Comment: Submitted to "Adaptive Optics-Assisted Integral-Field Spectroscopy",
Rutten R.G.M., Benn C.R., Mendez J., eds., May 2005, La Palma (Spain), New
Astr. Re
Lifting the Veil on Obscured Accretion: Active Galactic Nuclei Number Counts and Survey Strategies for Imaging Hard X-Ray Missions
Finding and characterizing the population of active galactic nuclei (AGNs) that produces the X-ray background (XRB) is necessary to connect the history of accretion to observations of galaxy evolution at longer wavelengths. The year 2012 will see the deployment of the first hard X-ray imaging telescope which, through deep extragalactic surveys, will be able to measure the AGN population at the energies where the XRB peaks (~20-30 keV). Here, we present predictions of AGN number counts in three hard X-ray bandpasses: 6-10 keV, 10-30 keV, and 30-60 keV. Separate predictions are presented for the number counts of Compton thick AGNs, the most heavily obscured active galaxies. The number counts are calculated for five different models of the XRB that differ in the assumed hard X-ray luminosity function, the evolution of the Compton thick AGNs, and the underlying AGN spectral model. The majority of the hard X-ray number counts will be Compton thin AGNs, but there is a greater than tenfold increase in the Compton thick number counts from the 6-10 keV to the 10-30 keV band. The Compton thick population shows enough variation that a hard X-ray number counts measurement will constrain the models. The computed number counts are used to consider various survey strategies for the NuSTAR mission, assuming a total exposure time of 6.2 Ms. We find that multiple surveys will allow a measurement of Compton thick evolution. The predictions presented here should be useful for all future imaging hard X-ray missions
On the lack of correlation between Mg II 2796, 2803 Angstrom and Lyman alpha emission in lensed star-forming galaxies
We examine the Mg II 2796, 2803 Angstrom, Lyman alpha, and nebular line
emission in five bright star-forming galaxies at 1.66<z<1.91 that have been
gravitationally lensed by foreground galaxy clusters. All five galaxies show
prominent Mg II emission and absorption in a P Cygni profile. We find no
correlation between the equivalent widths of Mg II and Lyman alpha emission.
The Mg II emission has a broader range of velocities than do the nebular
emission line profiles; the Mg II emission is redshifted with respect to
systemic by 100 to 200 km/s. When present, Lyman alpha is even more redshifted.
The reddest components of Mg II and Lyman alpha emission have tails to 500-600
km/s, implying a strong outflow. The lack of correlation in the Mg II and Lyman
alpha equivalent widths, the differing velocity profiles, and the high ratios
of Mg II to nebular line fluxes together suggest that the bulk of Mg II
emission does not ultimately arise as nebular line emission, but may instead be
reprocessed stellar continuum emission.Comment: The Astrophysical Journal, in press. 6 pages, 2 figure
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