706 research outputs found
Selected online learning experiences in the Caribbean during COVID-19
This study examines how ICTs have supported equitable development of online distance learning for students in primary, secondary, and tertiary education systems across the Caribbean. By presenting data obtained through interviews with government officials and other key stakeholders in five countries and territories - Barbados, the British Virgin Islands, Guyana, Jamaica, and Trinidad and Tobago â the study highlights learning continuity challenges and successful adaptations specific to the subregion during the COVID-19 pandemic. The study identifies best practices and recommendations to integrate ICTs in education systems during the pandemic and to âbuild back betterâ national education systems towards greater efficacy and inclusivity across student populations
Using Digital Tools to Train Health Emergencies Personnel in Fragile Contexts
The Leadership in Emergencies learning programme, launched in 2019, was designed to strengthen the competencies of World Health Organization (WHO) and Member State staff in teamwork, decision-making and communication, key skills required to lead effectively in emergencies. While the programme was initially used to train 43 staff in a workshop setting, the COVID-19 pandemic required a new remote approach. An online learning environment was developed using a variety of digital tools including WHO's open learning platform, OpenWHO.org. The strategic use of these technologies enabled WHO to dramatically expand access to the programme for personnel responding to health emergencies in fragile contexts and increase participation among key groups that were previously underserved.publishedVersionPeer reviewe
Digitalizing WHOâs Health Emergency Leadership Training During the Pandemic
publishedVersionPeer reviewe
Symbolic Formulae for Linear Mixed Models
A statistical model is a mathematical representation of an often simplified
or idealised data-generating process. In this paper, we focus on a particular
type of statistical model, called linear mixed models (LMMs), that is widely
used in many disciplines e.g.~agriculture, ecology, econometrics, psychology.
Mixed models, also commonly known as multi-level, nested, hierarchical or panel
data models, incorporate a combination of fixed and random effects, with LMMs
being a special case. The inclusion of random effects in particular gives LMMs
considerable flexibility in accounting for many types of complex correlated
structures often found in data. This flexibility, however, has given rise to a
number of ways by which an end-user can specify the precise form of the LMM
that they wish to fit in statistical software. In this paper, we review the
software design for specification of the LMM (and its special case, the linear
model), focusing in particular on the use of high-level symbolic model formulae
and two popular but contrasting R-packages in lme4 and asreml
Measuring the Effectiveness of Photoresponsive Nanocomposite Coatings on Aircraft Windshields to Mitigate Laser Intensity
In 2004, pilots reported 46 laser illumination events to the Federal Aviation Administration (FAA), with the number increasing to approximately 3,600 in 2011. Since that time, the number of reported laser incidents has ranged from 3,500 to 4,000. Previous studies indicate the potential for flight crewmember distraction from bright laser light being introduced to the cockpit. Compositional variations of the photoresponsive nanocomposite coatings were applied to an aircraft windscreen using a modified liquid dispersion/heating curing process. The attenuating effects of the deposited films on laser light intensity were evaluated using an optical power meter and the resultant laser intensity data through treated and untreated windscreens was collected. Data revealed a reduction in laser intensity (36â88%) in the presence of the engineered photoresponsive nanocomposite films. Results lend support of the view that the addition of transparent laser attenuating films applied to aircraft windscreens may improve flight safety, and reduce the risk from distraction or disruption of flight crewmembersâ vision
Evolutionary comparisons of chelonid alphaherpesvirus 5 (ChHV5) genomes from fibropapillomatosis-afflicted green (chelonia mydas), Ooive ridley (lepidochelys olivacea) and kempâs ridley (lepidochelys kempii) sea turtles
peer-reviewedThe spreading global sea turtle fibropapillomatosis (FP) epizootic is threatening some of
Earthâs ancient reptiles, adding to the plethora of threats faced by these keystone species.
Understanding this neoplastic disease and its likely aetiological pathogen, chelonid alphaherpesvirus 5 (ChHV5), is crucial to understand how the disease impacts sea turtle populations and species and the future trajectory of disease incidence. We generated 20 ChHV5 genomes, from three sea turtle species, to better understand the viral variant diversity and gene evolution of this oncogenic virus. We revealed previously underappreciated genetic diversity within this virus (with an average of 2035 single nucleotide polymorphisms (SNPs), 1.54% of the ChHV5 genome) and identified genes
under the strongest evolutionary pressure. Furthermore, we investigated the phylogeny of ChHV5 at both genome and gene level, confirming the propensity of the virus to be interspecific, with related variants able to infect multiple sea turtle species. Finally, we revealed unexpected intra-host diversity, with up to 0.15% of the viral genome varying between ChHV5 genomes isolated from different tumours concurrently arising within the same individual. These findings offer important insights into ChHV5 biology and provide genomic resources for this oncogenic viru
Physics, Astrophysics and Cosmology with Gravitational Waves
Gravitational wave detectors are already operating at interesting sensitivity
levels, and they have an upgrade path that should result in secure detections
by 2014. We review the physics of gravitational waves, how they interact with
detectors (bars and interferometers), and how these detectors operate. We study
the most likely sources of gravitational waves and review the data analysis
methods that are used to extract their signals from detector noise. Then we
consider the consequences of gravitational wave detections and observations for
physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version
<http://www.livingreviews.org/lrr-2009-2
Gravitational Waves From Known Pulsars: Results From The Initial Detector Era
We present the results of searches for gravitational waves from a large selection of pulsars using data from the most recent science runs (S6, VSR2 and VSR4) of the initial generation of interferometric gravitational wave detectors LIGO (Laser Interferometric Gravitational-wave Observatory) and Virgo. We do not see evidence for gravitational wave emission from any of the targeted sources but produce upper limits on the emission amplitude. We highlight the results from seven young pulsars with large spin-down luminosities. We reach within a factor of five of the canonical spin-down limit for all seven of these, whilst for the Crab and Vela pulsars we further surpass their spin-down limits. We present new or updated limits for 172 other pulsars (including both young and millisecond pulsars). Now that the detectors are undergoing major upgrades, and, for completeness, we bring together all of the most up-to-date results from all pulsars searched for during the operations of the first-generation LIGO, Virgo and GEO600 detectors. This gives a total of 195 pulsars including the most recent results described in this paper.United States National Science FoundationScience and Technology Facilities Council of the United KingdomMax-Planck-SocietyState of Niedersachsen/GermanyAustralian Research CouncilInternational Science Linkages program of the Commonwealth of AustraliaCouncil of Scientific and Industrial Research of IndiaIstituto Nazionale di Fisica Nucleare of ItalySpanish Ministerio de Economia y CompetitividadConselleria d'Economia Hisenda i Innovacio of the Govern de les Illes BalearsNetherlands Organisation for Scientific ResearchPolish Ministry of Science and Higher EducationFOCUS Programme of Foundation for Polish ScienceRoyal SocietyScottish Funding CouncilScottish Universities Physics AllianceNational Aeronautics and Space AdministrationOTKA of HungaryLyon Institute of Origins (LIO)National Research Foundation of KoreaIndustry CanadaProvince of Ontario through the Ministry of Economic Development and InnovationNational Science and Engineering Research Council CanadaCarnegie TrustLeverhulme TrustDavid and Lucile Packard FoundationResearch CorporationAlfred P. Sloan FoundationAstronom
First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data
Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of
continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a
fully coherent search, based on matched filtering, which uses the position and rotational parameters
obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto-
noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch
between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have
been developed, allowing a fully coherent search for gravitational waves from known pulsars over a
fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of
11 pulsars using data from Advanced LIGOâs first observing run. Although we have found several initial
outliers, further studies show no significant evidence for the presence of a gravitational wave signal.
Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of
the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for
the first time. For an additional 3 targets, the median upper limit across the search bands is below the
spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried
out so far
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