4,931 research outputs found
Discriminating active from latent tuberculosis in patients presenting to community clinics.
BACKGROUND: Because of the high global prevalence of latent TB infection (LTBI), a key challenge in endemic settings is distinguishing patients with active TB from patients with overlapping clinical symptoms without active TB but with co-existing LTBI. Current methods are insufficiently accurate. Plasma proteomic fingerprinting can resolve this difficulty by providing a molecular snapshot defining disease state that can be used to develop point-of-care diagnostics. METHODS: Plasma and clinical data were obtained prospectively from patients attending community TB clinics in Peru and from household contacts. Plasma was subjected to high-throughput proteomic profiling by mass spectrometry. Statistical pattern recognition methods were used to define mass spectral patterns that distinguished patients with active TB from symptomatic controls with or without LTBI. RESULTS: 156 patients with active TB and 110 symptomatic controls (patients with respiratory symptoms without active TB) were investigated. Active TB patients were distinguishable from undifferentiated symptomatic controls with accuracy of 87% (sensitivity 84%, specificity 90%), from symptomatic controls with LTBI (accuracy of 87%, sensitivity 89%, specificity 82%) and from symptomatic controls without LTBI (accuracy 90%, sensitivity 90%, specificity 92%). CONCLUSIONS: We show that active TB can be distinguished accurately from LTBI in symptomatic clinic attenders using a plasma proteomic fingerprint. Translation of biomarkers derived from this study into a robust and affordable point-of-care format will have significant implications for recognition and control of active TB in high prevalence settings
Gamma radiation survey of the LDEF spacecraft
The retrieval of the Long Duration Exposure Facility spacecraft in January 1990 after nearly six years in orbit offered a unique opportunity to study the long term buildup of induced radioactivity in the variety of materials on board. We conducted the first complete gamma-ray survey of a large spacecraft on LDEF shortly after its return to earth. A surprising observation was the Be-7 activity which was seen primarily on the leading edge of the satellite, implying that it was picked up by LDEF in orbit. This is the first known evidence for accretion of a radioactive isotope onto an orbiting spacecraft. Other isotopes observed during the survey, the strongest being Na-22, are all attributed to activation of spacecraft components. Be-7 is a spallation product of cosmic rays on nitrogen and oxygen in the upper atmosphere. However, the observed density is much greater than expected due to cosmic-ray production in situ. This implies transport of Be-7 from much lower altitudes up to the LDEF orbit
A Case Study of Health Risk Behaviors in a Sample of Residents in Rural Appalachia
The purpose of this paper was to examine health risk behaviors from a sample of adults living in one of the nationâs poorest counties in Central Appalachia. A descriptive secondary analysis of data collected for a public health surveillance project was conducted to determine the most pressing health problems and risk behaviors affecting this unique population. Residents reported high rates of hypertension, back pain, and sleep problems. They also reported very low levels of physical activity. A discussion of results is provided, including a comparison of the study population to information from national surveys. The limitations of the study and implications for social work practice, policy and research are also discussed
The puzzling case of the radio-loud QSO 3C 186: a gravitational wave recoiling black hole in a young radio source?
Context. Radio-loud AGNs with powerful relativistic jets are thought to be
associated with rapidly spinning black holes (BHs). BH spin-up may result from
a number of processes, including accretion of matter onto the BH itself, and
catastrophic events such as BH-BH mergers. Aims. We study the intriguing
properties of the powerful (L_bol ~ 10^47 erg s^-1) radio-loud quasar 3C 186.
This object shows peculiar features both in the images and in the spectra.
Methods. We utilize near-IR Hubble Space Telescope (HST) images to study the
properties of the host galaxy, and HST UV and Sloan Digital Sky Survey optical
spectra to study the kinematics of the source. Chandra X-ray data are also used
to better constrain the physical interpretation. Results. HST imaging shows
that the active nucleus is offset by 1.3 +- 0.1 arcsec (i.e. ~11 kpc) with
respect to the center of the host galaxy. Spectroscopic data show that the
broad emission lines are offset by -2140 +-390 km/s with respect to the narrow
lines. Velocity shifts are often seen in QSO spectra, in particular in
high-ionization broad emission lines. The host galaxy of the quasar displays a
distorted morphology with possible tidal features that are typical of the late
stages of a galaxy merger. Conclusions. A number of scenarios can be envisaged
to account for the observed features. While the presence of a peculiar outflow
cannot be completely ruled out, all of the observed features are consistent
with those expected if the QSO is associated with a gravitational wave (GW)
recoiling BH. Future detailed studies of this object will allow us to confirm
this type of scenario and will enable a better understanding of both the
physics of BH-BH mergers and the phenomena associated with the emission of GW
from astrophysical sources.Comment: 16 pages, 8 figures. Accepted for publication in Astronomy &
Astrophysics. New appendix adde
Transitioning to adulthood with a mild intellectual disability: Young people's experiences, expectations, and aspirations
Aim:
Very little attention has been paid to the views and experiences of young people with mild intellectual disabilities on the broad topics of adulthood and adult identity. The following study was undertaken to explore how young adults with mild intellectual disabilities conceptualize, relate to, and experience the process of transition.
Method:
Eight young adults with mild to borderline intellectual disabilities participated in semiâstructured interviews. Results were analysed using interpretive thematic analysis.
Results:
Two umbrella themes were identified: âOn a developmental pathwayâ and âNegotiations in the environmentâ.
Conclusions:
The participants concerns were surprisingly similar to those commonly expressed by young adults without disabilities. Selfâperceived adult identity appeared to be affected by the participants' personal definitions of adulthood, as well as by social comparisons with both peers and adults. Finally, while concerns were expressed about their capacity to cope with responsibility, most felt optimistic about adopting full adult status in the future
Isoflavones in Legumes as Functional Forages and Feeds in Ruminant Grazing Systems
Legumes are often utilized in livestock grazing systems to improve diet quality, diversity, and consequently animal performance. In addition to their nutritional utility, legumes contain phytoestrogenic isoflavones that have selective antimicrobial activity in the rumen and once absorbed can cause arterial vasodilation. These added bioactive functions of isoflavones suggest that legumes could be strategically utilized in grazing systems as functional forages to improve ruminant performance and health. The objective of this presentation will be to discuss past and current research on the application of isoflavones via legumes as an antimicrobial for growth promotion and as a mitigation strategy for fescue toxicosis in grazing ruminants
Variables associated with odds of finishing and finish time in a 161-km ultramarathon
We sought to determine the degree to which age, sex, calendar year, previous event experience and ambient race day temperature were associated with finishing a 100-mile (161-km) trail running race and with finish time in that race. We computed separate generalized linear mixed-effects regression models for (1) odds of finishing and (2) finish times of finishers. Every starter from 1986 to 2007 was used in computing the models for odds of finishing (8,282 starts by 3,956 individuals) and every finisher in the same period was included in the models for finish time (5,276 finishes). Factors associated with improved odds of finishing included being a first-time starter and advancing calendar year. Factors associated with reduced odds of finishing included advancing age above 38Â years and warmer weather. Beyond 38Â years of age, women had worse odds of finishing than men. Warmer weather had a similar effect on finish rates for men and women. Finish times were slower with advancing age, slower for women than men, and less affected by warm weather for women than for men. Calendar year was not associated with finish time after adjustment for other variables
When does the action start and finish? Making the case for an ethnographic action research in educational research
This paper explores how ethnographic and action research methodologies can be justifiably combined to create a new methodological approach in educational research. It draws on existing examples in both educational research and
development studies that have discussed the use of ethnography and action research in specific projects. Interpretations of ethnography and action research
are developed that aim to minimise the epistemological differences between them.
The paper also contextualises an âethnographic action researchâ approach with reference to an example of the authorâs research into participation in three âreceptionâ (first year of schooling) classes in the United Kingdom. It is argued that research into the theme of participation in early years education, using participative methods, was particularly suitable for this new methodological
approach
A fast and long-lived outflow from the supermassive black hole in NGC 5548
Supermassive black holes in the nuclei of active galaxies expel large amounts
of matter through powerful winds of ionized gas. The archetypal active galaxy
NGC 5548 has been studied for decades, and high-resolution X-ray and UV
observations have previously shown a persistent ionized outflow. An observing
campaign in 2013 with six space observatories shows the nucleus to be obscured
by a long-lasting, clumpy stream of ionized gas never seen before. It blocks
90% of the soft X-ray emission and causes simultaneous deep, broad UV
absorption troughs. The outflow velocities of this gas are up to five times
faster than those in the persistent outflow, and at a distance of only a few
light days from the nucleus, it may likely originate from the accretion disk.Comment: 25 pages, 8 figures. This is the author's version of the work. It is
posted here by permission of the AAAS for personal use, not for
redistribution. The definitive version was published in Science,
electronically available at Science Express (June 19, 2014). For a brief
video explaining the key results of this paper, please visit
http://www.issibern.ch/teams/ngc5548/?page_id=2
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