582 research outputs found
The Nature, Evolution, Clustering and X-ray Properties of Extremely Red Galaxies in the CDFS/GOODS field
We identify a deep sample of 198 extremely red objects (EROs) in (50.4 sq.
arcmin of) the Chandra Deep Field South, selected as I-K>3.92 galaxies to a
limit K=22. The ERO number counts remain well below the predictions for pure
luminosity evolution, and fall below even a non-evolving model, suggesting the
comoving number density of passive/very red galaxies decreases with redshift.
The angular correlation function of these EROs indicates stronger clustering
than that of other galaxies at the same magnitudes, and is best-fitted by
models in which the EROs have a comoving correlation radius 12.5/h Mpc, or
21.4/h Mpc in a stable clustering model. We find a 40-arcsec diameter grouping
of 10 EROs, centered on the Chandra source (and ERO) XID:58, with colours
suggesting a cluster of mostly passive EROs at approx. z=1.5. The 942 ksec
Chandra survey detected 73 X-ray sources in the area of our ERO sample, of
which 17 coincide with EROs. Of these sources, 13 have X-ray properties
indicative of obscured AGN, while the faintest 4 may be starburst galaxies. In
addition, we find evidence that Chandra sources and EROs are positively
cross-correlated at non-zero (2-20 arcsec) separations, implying that they tend
to trace the same large-scale structures.Comment: 17 pages, latex, 14 figures, accepted for publication in MNRAS. Major
revisions from original version, with a new, reselected sample of ERO
The Assembly of Diversity in the Morphologies and Stellar Populations of High-Redshift Galaxies
We have studied the evolution in the morphologies, sizes, stellar-masses,
colors, and internal color dispersion (ICD) of galaxies at z=1 and 2.3, using a
near-IR, flux-limited catalog for the HDF-N. At z=1 most luminous galaxies have
morphologies of early-to-mid Hubble-types, and many show transformations
between their rest-frame UV-optical morphologies. Galaxies at z=2.3 have
compact and irregular morphologies with no clearly evident Hubble-sequence
candidates. The mean galaxy size grows from z=2.3 to 1 by 40%, and the density
of galaxies larger than 3 kpc increases by 7 times. At z=1, the size-luminosity
distribution is broadly consistent with that of local galaxies, with passive
evolution. However, galaxies at z=2.3 are smaller than the large present-day
galaxies, and must continue to grow in size and stellar mass. We have measured
the galaxies' UV-optical ICD, which quantifies differences in morphology and
the relative amount of on-going star-formation. The mean and scatter in
galaxies' total colors and ICD increase from z=2.3 to 1. At z=1 many galaxies
with large ICD are spirals, with a few irregular systems. Few z=2.3 galaxies
have high ICD, and those that do are actively merging. We interpret this as
evidence for the presence of older and more diverse stellar populations at z=1
that are not generally present at z>2. We conclude that the star-formation
histories of galaxies at z>2 are dominated by discrete, recurrent bursts, which
quickly homogenize the galaxies' stellar content, and are possibly associated
with mergers. The increase in the stellar-population diversification by z<1.4
implies that merger-induced starbursts occur less frequently than at higher
redshifts, and more quiescent star-forming modes dominate. This transition
coincides with the emergence of Hubble-sequence galaxies. [Abridged]Comment: Accepted for publication in the Astrophysical Journal. 20 pages, in
emulateapj forma
Holding the Line And Then Crossing It
We presented a performance-paper in 5 voices that gently challenged how power is held in higher education arts institutions. Playfully exploring with the metaphor of the line, and using string telephones, we staged a 5-way conversation, made up of speculative questions and silences. We considered what a radically gentle learning environment might look like, all the time interrogating the real connotations of the word âgentleâ, and how it might sit alongside terms like discomfort, tradition, privilege and opacity. How can listening happen in a way that matters? Drawing on thinking about response-ability (Haraway 2008, 2016, Stengers 2014), care (Puig de la Bellacasa 2017, Baan Hofman 2023), complaints (Ahmed 2021), engaged pedagogy (hooks 2003), and the current social justice work of Tema Okun, as well as our own institutional experiences, we offered fabulations of alternative spaces for art-making, sharing and educating. We asked, how might a Higher Education Institution which prioritises listening, slow work and transparency fit within todayâs society? More importantly, how might educators and learners, communities and publics, who experience being listened to and who have been allowed to co-imagine their futures, then begin to shape and reconfigure society more broadly
Inhaler technique mastery and maintenance in healthcare professionals trained on different devices
Peer reviewedPostprin
Effectiveness of inhaler devices in adult asthma and COPD
Peer reviewedPublisher PD
Applying Spatial Analysis Tools in Public Health: An Example Using SaTScan to Detect Geographic Targets for Colorectal Cancer Screening Interventions
Epidemiologists are gradually incorporating spatial analysis into health-related research as geocoded cases of disease become widely available and health-focused geospatial computer applications are developed. One health-focused application of spatial analysis is cluster detection. Using cluster detection to identify geographic areas with high-risk populations and then screening those populations for disease can improve cancer control. SaTScan is a free cluster-detection software application used by epidemiologists around the world to describe spatial clusters of infectious and chronic disease, as well as disease vectors and risk factors. The objectives of this article are to describe how spatial analysis can be used in cancer control to detect geographic areas in need of colorectal cancer screening intervention, identify issues commonly encountered by SaTScan users, detail how to select the appropriate methods for using SaTScan, and explain how method selection can affect results. As an example, we used various methods to detect areas in Florida where the population is at high risk for late-stage diagnosis of colorectal cancer. We found that much of our analysis was underpowered and that no single method detected all clusters of statistical or public health significance. However, all methods detected 1 area as high risk; this area is potentially a priority area for a screening intervention. Cluster detection can be incorporated into routine public health operations, but the challenge is to identify areas in which the burden of disease can be alleviated through public health intervention. Reliance on SaTScanâs default settings does not always produce pertinent results
Characteristics of patients making serious inhaler errors with a dry powder inhaler and association with asthma-related events in a primary care setting
Acknowledgements The iHARP database was funded by unrestricted grants from Mundipharma International Ltd and Research in Real-Life Ltd; these analyses were funded by an unrestricted grant from Teva Pharmaceuticals. Mundipharma and Teva played no role in study conduct or analysis and did not modify or approve the manuscript. The authors wish to direct a special appreciation to all the participants of the iHARP group who contributed data to this study and to Mundipharma, sponsors of the iHARP group. In addition, we thank Julie von Ziegenweidt for assistance with data extraction and Anna Gilchrist and Valerie L. Ashton, PhD, for editorial assistance. Elizabeth V. Hillyer, DVM, provided editorial and writing support, funded by Research in Real-Life, Ltd.Peer reviewedPublisher PD
Thyroid Cancer Incidence in New Jersey: Time Trend, Birth Cohort and Socioeconomic Status Analysis (1979â2006)
The study's purpose was to investigate thyroid cancer incidence time trends, birth cohort effects, and association with socioeconomic status (SES) in New Jersey (NJ), a high incidence state, using NJ State Cancer Registry data. Thyroid cancer incidence rates in each sex, nearly all age groups, two major histologies and all stages significantly increased between 1979 and 2006. For each sex, age-specific incidence rates began greatly increasing in the 1924 birth cohort and, generally, the highest thyroid cancer incidence rate for each five-year age group occurred in the latest birth cohort and diagnosis period. Thyroid cancer incidence rates were significantly higher in NJ Census tracts with higher SES and in counties with a higher percentage of insured residents. These results support further investigation into the relationship between rising thyroid cancer incidence and increasing population exposure to medical (including diagnostic) radiation, as well as widespread use of more sensitive diagnostic techniques
The soft X-ray Cluster-AGN spatial cross-correlation function in the ROSAT-NEP survey
X-ray surveys facilitate investigations of the environment of AGNs. Deep
Chandra observations revealed that the AGNs source surface density rises near
clusters of galaxies. The natural extension of these works is the measurement
of spatial clustering of AGNs around clusters and the investigation of relative
biasing between active galactic nuclei and galaxies near clusters. The major
aims of this work are to obtain a measurement of the correlation length of AGNs
around clusters and a measure of the averaged clustering properties of a
complete sample of AGNs in dense environments. We present the first measurement
of the soft X-ray cluster-AGN cross-correlation function in redshift space
using the data of the ROSAT-NEP survey. The survey covers 9x9 deg^2 around the
North Ecliptic Pole where 442 X-ray sources were detected and almost completely
spectroscopically identified. We detected a > 3 sigma significant clustering
signal on scales s<50 h_70^-1 Mpc. We performed a classical maximum-likelihood
power-law fit to the data and obtained a correlation length s_0=8.7^+1.2_-0.3
h70^-1 Mpc and a slope gamma=1.7^+0.2_-0.7 (1 sigma errors). This is a strong
evidence that AGNs are good tracers of the large scale structure of the
Universe. Our data were compared to the results obtained by cross-correlating
X-ray clusters and galaxies. We observe, with a large uncertainty, a similar
behaviour of the AGNs clustering around clusters similar to the clustering of
galaxies around clusters.Comment: 7 pages, 6 figures, Accepted by A&
The Iron abundance in Galactic Planetary Nebulae
We constrain the iron abundance in a sample of 33 low-ionization Galactic
planetary nebulae (PNe) using [Fe III] lines and correcting for the
contribution of higher ionization states with ionization correction factors
(ICFs) that take into account uncertainties in the atomic data. We find very
low iron abundances in all the objects, suggesting that more than 90% of their
iron atoms are condensed onto dust grains. This number is based on the solar
iron abundance and implies a lower limit on the dust-to-gas mass ratio, due
solely to iron, of M_dust/M_gas>1.3x10^{-3} for our sample. The depletion
factors of different PNe cover about two orders of magnitude, probably
reflecting differences in the formation, growth, or destruction of their dust
grains. However, we do not find any systematic difference between the gaseous
iron abundances calculated for C-rich and O-rich PNe, suggesting similar iron
depletion efficiencies in both environments. The iron abundances of our sample
PNe are similar to those derived following the same procedure for a group of 10
Galactic H II regions. These high depletion factors argue for high depletion
efficiencies of refractory elements onto dust grains both in molecular clouds
and AGB stars, and low dust destruction efficiencies both in interstellar and
circumstellar ionized gas.Comment: Accepted for publication in ApJ. 15 pages, 4 Postscript figures,
corrected typos, Tables 2 and 3 correcte
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