2,514 research outputs found

    Crowdsourcing the Disaster Management Cycle

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    Crowdsourcing is a communication platform that can be used during and after a disastrous event. Previous research in crisis crowdsourcing demonstrates its wide adoption for aiding response efforts by non-government organizations and public citizens. There is a gap in understanding the government use of crowdsourcing for emergency management, and in the use of crowdsourcing for mitigation and preparedness. This research aims to characterize crowdsourcing in all phases of the disaster management cycle by government agencies in Canada and the USA. Semi-structured interviews conducted with 22 government officials from both countries reveal that crisis crowdsourced information is used in all phases of the disaster management cycle, though direct crowdsourcing is yet to be applied in the pre-disaster phases. Emergency management officials and scholars have an opportunity to discover new ways to directly use crowdsourcing for mitigation and preparedness

    Mid-infrared Selection of Active Galactic Nuclei with the Wide-Field Infrared Survey Explorer. I. Characterizing WISE-selected Active Galactic Nuclei in COSMOS

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    The Wide-field Infrared Survey Explorer (WISE) is an extremely capable and efficient black hole finder. We present a simple mid-infrared color criterion, W1 ā€“ W2 ā‰„ 0.8 (i.e., [3.4]ā€“[4.6] ā‰„0.8, Vega), which identifies 61.9 Ā± 5.4 active galactic nucleus (AGN) candidates per deg^2 to a depth of W2 ~ 15.0. This implies a much larger census of luminous AGNs than found by typical wide-area surveys, attributable to the fact that mid-infrared selection identifies both unobscured (type 1) and obscured (type 2) AGNs. Optical and soft X-ray surveys alone are highly biased toward only unobscured AGNs, while this simple WISE selection likely identifies even heavily obscured, Compton-thick AGNs. Using deep, public data in the COSMOS field, we explore the properties of WISE-selected AGN candidates. At the mid-infrared depth considered, 160 Ī¼Jy at 4.6 Ī¼m, this simple criterion identifies 78% of Spitzer mid-infrared AGN candidates according to the criteria of Stern et al. and the reliability is 95%. We explore the demographics, multiwavelength properties and redshift distribution of WISE-selected AGN candidates in the COSMOS field

    Mineral magnetism of dusty olivine:A credible recorder of pre-accretionary remanence

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    The magnetic properties of olivine-hosted Fe-Ni particles have been studied to assess the potential of ā€œdusty olivineā€ to retain a pre-accretionary remanence in chondritic meteorites. Both body-centered (bcc) and face-centered cubic (fcc) Fe-Ni phases were formed by reduction of a terrestrial olivine precursor. The presence of Ni complicates the magnetic properties during heating and cooling due to the fcc-bcc martensitic transition. First-order reversal curve (FORC) diagrams contain a central ridge with a broad coercivity distribution extending to 600 mT, attributed to non-interacting single-domain (SD) particles, and a ā€œbutterflyā€ structure extending to 250 mT, attributed to single-vortex (SV) states. SD and SV states were imaged directly using electron holography. The location of the SD/SV boundary is broadly consistent with theoretical predictions. A method to measure the volume of individual SD particles using electron holography is presented. Combining the volume information with constraints on coercivity, we calculate the thermal relaxation characteristics of the particles and demonstrate that the high-coercivity component of remanance would remain stable for 4.6 Ga, even at temperatures approaching the Curie temperature of pure Fe. The high coercivity of the particles, together with the chemical protection offered by the surrounding olivine, is likely to make them resistant to shock remagnetization, isothermal remagnetization and terrestrial weathering, making dusty olivine a credible recorder of pre-accretionary magnetic fields

    A database of microRNA expression patterns in Xenopus laevis

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    MicroRNAs (miRNAs) are short, non-coding RNAs around 22 nucleotides long. They inhibit gene expression either by translational repression or by causing the degradation of the mRNAs they bind to. Many are highly conserved amongst diverse organisms and have restricted spatio-temporal expression patterns during embryonic development where they are thought to be involved in generating accuracy of developmental timing and in supporting cell fate decisions and tissue identity. We determined the expression patterns of 180 miRNAs in Xenopus laevis embryos using LNA oligonucleotides. In addition we carried out small RNA-seq on different stages of early Xenopus development, identified 44 miRNAs belonging to 29 new families and characterized the expression of 5 of these. Our analyses identified miRNA expression in many organs of the developing embryo. In particular a large number were expressed in neural tissue and in the somites. Surprisingly none of the miRNAs we have looked at show expression in the heart. Our results have been made freely available as a resource in both XenMARK and Xenbase

    The effect of d-cycloserine on brain processing of breathlessness over pulmonary rehabilitation: an experimental medicine study

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    Research questionPulmonary rehabilitation is the best treatment for chronic breathlessness in COPD but there remains an unmet need to improve efficacy. Pulmonary rehabilitation has strong parallels with exposure-based cognitive behavioural therapies (CBT), both clinically and in terms of brain activity patterns. The partial N-methyl-d-aspartate (NMDA)-receptor agonistd-cycloserine has shown promising results in enhancing efficacy of CBT, thus we hypothesised that it would similarly augment the effects of pulmonary rehabilitation in the brain. Positive findings would support further development in phase 3 clinical trials.Methods72 participants with mild-to-moderate COPD were recruited to a double-blind pre-registered (ClinicalTrials.govidentifier:NCT01985750) experimental medicine study running parallel to a pulmonary rehabilitation course. Participants were randomised to 250ā€…mgd-cycloserine or placebo, administered immediately prior to the first four sessions of pulmonary rehabilitation. Primary outcome measures were differences betweend-cycloserine and placebo in brain activity in the anterior insula, posterior insula, anterior cingulate cortices, amygdala and hippocampus following completion of pulmonary rehabilitation. Secondary outcomes included the same measures at an intermediate time point and voxel-wise difference across wider brain regions. An exploratory analysis determined the interaction with breathlessness anxiety.ResultsNo difference betweend-cycloserine and placebo groups was observed across the primary or secondary outcome measures.d-cycloserine was shown instead to interact with changes in breathlessness anxiety to dampen reactivity to breathlessness cues. Questionnaire and measures of respiratory function showed no group difference. This is the first study testing brain-active drugs in pulmonary rehabilitation. Rigorous trial methodology and validated surrogate end-points maximised statistical power.ConclusionAlthough increasing evidence supports therapeutic modulation of NMDA pathways to treat symptoms, we conclude that a phase 3 clinical trial ofd-cycloserine would not be worthwhile

    Endotracheal intubation skill acquisition by medical students

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    During the course of their training, medical students may receive introductory experience with advanced resuscitation skills. Endotracheal intubation (ETI ā€“ the insertion of a breathing tube into the trachea) is an example of an important advanced resuscitation intervention. Only limited data characterize clinical ETI skill acquisition by medical students. We sought to characterize medical student acquisition of ETI procedural skill.11Presented as a poster discussion on 17 October 2007 at the annual meeting of the American Society of Anesthesiologists in San Francisco, CA.The study included third-year medical students participating in a required anesthesiology clerkship. Students performed ETI on operating room patients under the supervision of attending anesthesiologists. Students reported clinical details of each ETI effort, including patient age, sex, Mallampati score, number of direct laryngoscopies and ETI success. Using mixed-effects regression, we characterized the adjusted association between ETI success and cumulative ETI experience.ETI was attempted by 178 students on 1,646 patients (range 1ā€“23 patients per student; median 9 patients per student, IQR 6ā€“12). Overall ETI success was 75.0% (95% CI 72.9ā€“77.1%). Adjusted for patient age, sex, Mallampati score and number of laryngoscopies, the odds of ETI success improved with cumulative ETI encounters (odds ratio 1.09 per additional ETI encounter; 95% CI 1.04ā€“1.14). Students required at least 17 ETI encounters to achieve 90% predicted ETI success.In this series medical student ETI proficiency was associated with cumulative clinical procedural experience. Clinical experience may provide a viable strategy for fostering medical student procedural skills
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