15,229 research outputs found
Self-reported “communication technology” usage in patients attending a cardiology outpatient clinic in a remote regional hospital
Peer reviewedPublisher PD
Genome editing in non-model organisms opens new horizons for comparative physiology
For almost 100 years, biologists have made fundamental discoveries using a handful of model organisms that are not representative of the rich diversity found in nature. The advent of CRISPR genome editing now opens up a wide range of new organisms to mechanistic investigation. This increases not only the taxonomic breadth of current research but also the scope of biological problems that are now amenable to study, such as population control of invasive species, management of disease vectors such as mosquitoes, the creation of chimeric animal hosts to grow human organs and even the possibility of resurrecting extinct species such as passenger pigeons and mammoths. Beyond these practical applications, work on non-model organisms enriches our basic understanding of the natural world. This special issue addresses a broad spectrum of biological problems in non-model organisms and highlights the utility of genome editing across levels of complexity from development and physiology to behaviour and evolution
Infrared Spectral Energy Distribution Model for Extremely Young Galaxies
The small grain sizes produced by Type II supernova (SN II) models in young,
metal-poor galaxies make the appearance of their infrared (IR) spectral energy
distribution (SED) quite different from that of nearby, older galaxies. To
study this effect, we have developed a model for the evolution of dust content
and the IR SED of low-metallicity, extremely young galaxies based on Hirashita
et al. (2002). We find that, even in the intense ultraviolet (UV) radiation
field of very young galaxies, small silicate grains are subject to stochastic
heating resulting in a broad temperature distribution and substantial MIR
continuum emission. Larger carbonaceous grains are in thermal equilibrium at T
\simeq 50 - 100K, and they also contribute to the MIR. We present the evolution
of SEDs and IR extinction of very young, low-metallicity galaxies. The IR
extinction curve is also shown. In the first few Myrs, the emission peaks at
\lambda \sim 30-50um at later times dust self-absorption decreases the apparent
grain temperatures, shifting the bulk of the emission into the submillimetre
band. We successfully apply the model to the IR SED of a low metallicity (1/41
Z_\odot) dwarf galaxy SBS0335-052. We find the SED, optical properties and
extinction of the star forming region to be consistent with a very young and
compact starburst. We also predict the SED of another extremely low-metallicity
galaxy, I Zw 18, for future observational tests. Some prospects for future
observations are discussed.Comment: MNRAS in press, pages, 6 figures, using mn2e.cls. Abstract abridge
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Evaluating duration of response to treatment in systemic lupus erythematosus clinical trials.
ObjectiveTo evaluate response duration and identify predictors of transitioning into and out of the response state in patients with SLE receiving standard of care (SoC) in 52-week clinical trials.MethodsA multistate model (MSM) allowing for bidirectional transitions between response and non-response states was fit to data on 759 patients with SLE with active disease randomised to SoC. The probability of being in response at 52 weeks, average duration of response (sojourn time) and mean total time in response for SLE Responder Index (SRI-4, SRI-5, SRI-6) and BILAG-based Composite Lupus Assessment (BICLA) were estimated. Predictors of attainment and loss of SRI-5 response were also assessed.ResultsThe MSM estimated probability of being in response at 52 weeks ranged from 42% (SRI-6) to 61% (SRI-4). Mean duration of response ranged from 20.4 weeks (BICLA) to 31.5 weeks (SRI-4). Mean total time in response was 16.4-24.8 weeks. Baseline characteristics predictive of shorter SRI-5 response duration were African descent (p=0.005), longer history of disease (p=0.03), higher anti-dsDNA antibody titres (p=0.039), lower lymphocyte count (p=0.008) and lower haemoglobin (p=0.006). Younger age (p<0.001) and higher protein/creatinine ratio (p<0.001) were associated with higher likelihood of achieving SRI-5 but also shorter response duration.ConclusionFactors associated with disease severity were more predictive of shorter response duration than of 52-week response status. Analysing landmark response rates and response duration using MSM may be a more powerful way to distinguish effective investigational treatments from background SoC, although this remains to be evaluated in future trials
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