11 research outputs found
Using radio galaxies to find super-structures
Radio galaxies are excellent at tracing large-scale structure due to their
high bias. We present new results from the TONS08 radio galaxy redshift survey.
We find unequivocal evidence for a huge (at least 80 x 80 x 100 Mpc^3)
super-structure at redshift z=0.27, confirming tentative evidence for such a
structure from the 7C redshift survey (7CRS). A second, newly discovered
super-structure is also tentatively found at redshift 0.35 (of dimensions at
least 100 x 100 x 100 Mpc^3). Out of the total sample size of 84 radio
galaxies, at least 25 are associated with the two super-structures. We use
quasi-linear structure formation theory to estimate the number of such
structures expected in the TONS08 volume if the canonical value for radio
galaxy bias is assumed. Under this assumption, the structures represent ~ 4-5
sigma peaks in the primordial density field and their expected number is low
(10^{-2}-10^{-4}). Fortunately, there are several plausible explanations (many
of which are testable) for these low probabilities in the form of potential
mechanisms for boosting the bias on large scales. These include: the
association of radio galaxies with highly biased rich clusters in
super-structures, enhanced triggering by group/group mergers, and enhanced
triggering and/or redshift space distortion in collapsing systems as the growth
of super-structures moves into the non-linear regime. Similar structures could
have been missed in previous surveys because of the effects of Poisson-sampling
fluctuations.Comment: 6 pages, 3 figures. To appear in "Radio galaxies: past, present and
future", eds M. Jarvis et al., Leiden, Nov 200
Applications of Wearable Technology in a Real-Life Setting in People with Knee Osteoarthritis: A Systematic Scoping Review
With the growing number of people affected by osteoarthritis, wearable technology may enable the provision of care outside a traditional clinical setting and thus transform how healthcare is delivered for this patient group. Here, we mapped the available empirical evidence on the utilization of wearable technology in a real-world setting in people with knee osteoarthritis. From an analysis of 68 studies, we found that the use of accelerometers for physical activity assessment is the most prevalent mode of use of wearable technology in this population. We identify low technical complexity and cost, ability to connect with a healthcare professional, and consistency in the analysis of the data as the most critical facilitators for the feasibility of using wearable technology in a real-world setting. To fully realize the clinical potential of wearable technology for people with knee osteoarthritis, this review highlights the need for more research employing wearables for information sharing and treatment, increased inter-study consistency through standardization and improved reporting, and increased representation of vulnerable populations
Two 100 Mpc-scale structures in the 3-D distribution of radio galaxies and their implications
We present unequivocal evidence for a huge (~80 x 100 x 100 Mpc^3)
super-structure at redshift z=0.27 in the 3-D distribution of radio galaxies
from the TONS08 sample, confirming tentative evidence for such a structure from
the 7C redshift survey (7CRS). A second, newly discovered super-structure is
also less securely found at redshift 0.35 (of dimensions ~100 x 100 x 100
Mpc^3). We present full observational details on the TONS08 sample which was
constructed to probe structures in the redshift range 0 < z < 0.5 by matching
NVSS sources with objects in APM catalogues to obtain a sample of optically
bright (E ~ R 3 mJy) radio
galaxies in the same 25 deg^2 area as part-II of the 7CRS. Out of the total
sample size of 84 radio galaxies, at least 25 are associated with the two ~100
Mpc-scale super-structures. We use quasi-linear structure formation theory to
estimate the number of such structures expected in the TONS08 volume if the
canonical value for radio galaxy bias is assumed. Under this assumption, the
structures represent ~ 4-5 sigma peaks in the primordial density field and
their expected number is low (~10^-2 - 10^-4). Fortunately, there are several
plausible explanations (many of which are testable) for these low probabilities
in the form of potential mechanisms for boosting the bias on large scales.
These include: the association of radio galaxies with highly biased rich
clusters in super-structures, enhanced triggering by group/group mergers, and
enhanced triggering and/or redshift space distortion in collapsing systems as
the growth of super-structures moves into the non-linear regime (abridged).Comment: Accepted for publication in MNRAS. 26 pages,16 figures. spectra can
be found in: http://www-astro.physics.ox.ac.uk/~brand/08_paper.ps.g
The Sparkler: Evolved High-Redshift Globular Clusters Captured by JWST
Using data from JWST, we analyze the compact sources ("sparkles") located
around a remarkable galaxy (the "Sparkler") that is
strongly gravitationally lensed by the galaxy cluster SMACS
J0723.3-7327. Several of these compact sources can be cross-identified in
multiple images, making it clear that they are associated with the host galaxy.
Combining data from JWST's {\em Near-Infrared Camera} (NIRCam) with archival
data from the {\em Hubble Space Telescope} (HST), we perform 0.4-4.4m
photometry on these objects, finding several of them to be very red and
consistent with the colors of quenched, old stellar systems. Morphological fits
confirm that these red sources are spatially unresolved even in strongly
magnified JWST/NIRCam images, while JWST/NIRISS spectra show [OIII]5007
emission in the body of the Sparkler but no indication of star formation in the
red compact sparkles. The most natural interpretation of these compact red
companions to the Sparkler is that they are evolved globular clusters seen at
. Applying \textsc{Dense Basis} SED-fitting to the sample, we infer
formation redshifts of for these globular cluster
candidates, corresponding to ages of Gyr at the epoch of
observation and a formation time just 0.5~Gyr after the Big Bang. If
confirmed with additional spectroscopy, these red, compact "sparkles" represent
the first evolved globular clusters found at high redshift, could be amongst
the earliest observed objects to have quenched their star formation in the
Universe, and may open a new window into understanding globular cluster
formation. Data and code to reproduce our results will be made available at
\faGithub\href{https://niriss.github.io/sparkler.html}{http://canucs-jwst.com/sparkler.html}.Comment: Submitted to ApJL. Comments are welcome. Data and code to reproduce
our results will be made available at niriss.github.io/sparkler.htm
Recommended from our members
A solution scan of societal options to reduce transmission and spread of respiratory viruses: SARS-CoV-2 as a case study.
Societal biosecurity - measures built into everyday society to minimize risks from pests and diseases - is an important aspect of managing epidemics and pandemics. We aimed to identify societal options for reducing the transmission and spread of respiratory viruses. We used SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) as a case study to meet the immediate need to manage the COVID-19 pandemic and eventually transition to more normal societal conditions, and to catalog options for managing similar pandemics in the future. We used a 'solution scanning' approach. We read the literature; consulted psychology, public health, medical, and solution scanning experts; crowd-sourced options using social media; and collated comments on a preprint. Here, we present a list of 519 possible measures to reduce SARS-CoV-2 transmission and spread. We provide a long list of options for policymakers and businesses to consider when designing biosecurity plans to combat SARS-CoV-2 and similar pathogens in the future. We also developed an online application to help with this process. We encourage testing of actions, documentation of outcomes, revisions to the current list, and the addition of further options
Tapping into non-English-language science for the conservation of global biodiversity.
The widely held assumption that any important scientific information would be available in English underlies the underuse of non-English-language science across disciplines. However, non-English-language science is expected to bring unique and valuable scientific information, especially in disciplines where the evidence is patchy, and for emergent issues where synthesising available evidence is an urgent challenge. Yet such contribution of non-English-language science to scientific communities and the application of science is rarely quantified. Here, we show that non-English-language studies provide crucial evidence for informing global biodiversity conservation. By screening 419,679 peer-reviewed papers in 16 languages, we identified 1,234 non-English-language studies providing evidence on the effectiveness of biodiversity conservation interventions, compared to 4,412 English-language studies identified with the same criteria. Relevant non-English-language studies are being published at an increasing rate in 6 out of the 12 languages where there were a sufficient number of relevant studies. Incorporating non-English-language studies can expand the geographical coverage (i.e., the number of 2° × 2° grid cells with relevant studies) of English-language evidence by 12% to 25%, especially in biodiverse regions, and taxonomic coverage (i.e., the number of species covered by the relevant studies) by 5% to 32%, although they do tend to be based on less robust study designs. Our results show that synthesising non-English-language studies is key to overcoming the widespread lack of local, context-dependent evidence and facilitating evidence-based conservation globally. We urge wider disciplines to rigorously reassess the untapped potential of non-English-language science in informing decisions to address other global challenges. Please see the Supporting information files for Alternative Language Abstracts
Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study
Purpose:
Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom.
Methods:
Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded.
Results:
The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia.
Conclusion:
We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes
Guidance for the prevention, testing, treatment and management of hepatitis C in primary care.
1. Hepatitis C infection is an under-diagnosed (five out of every six people infected are undiagnosed) and under-treated important cause of morbidity and mortality.
2. Hepatitis C is a common and potentially curable disease, but only 1 to 2% of infected people are currently receiving National Institute of Clinical Excellence (NICE) recommended therapy.
3. Every general practitioner is likely to have between 8 to 18 infected individuals per GP, based on an average list size of 1,800 and, partly depending upon local population demographics. Many of these patients may not be diagnosed and knowledge about HCV in population and primary care remains low but improving.
4. Prevalence of the hepatitis C virus (HCV) is estimated to be between 0.4 to 1% of the United Kingdom (UK) population, equating to be between 250,000 to 600,000 sufferers. Worldwide there are an estimated 170 million people, about 3% of the world’s population, who are chronically infected with HCV.
5. HCV is a blood-borne ribonucleic acid (RNA) virus that exists as a number of different strains (genotypes) and an important cause of liver disease. The effects of the infection vary from one individual to the next. Some people will remain symptom free, some will develop cirrhosis and others will develop liver failure or hepatocellular (primary liver) cancer