39 research outputs found
State of the world’s plants and fungi 2020
Kew’s State of the World’s Plants and Fungi project provides assessments of our current knowledge of the diversity of plants and fungi on Earth, the global threats that they face, and the policies to safeguard them. Produced in conjunction with an international scientific symposium, Kew’s State of the World’s Plants and Fungi sets an important international standard from which we can annually track trends in the global status of plant and fungal diversity
Multi-wavelength observations of blazar AO 0235+164 in the 2008-2009 flaring state
The blazar AO 0235+164 (z = 0.94) has been one of the most active objects observed by Fermi Large Area Telescope (LAT) since its launch in Summer 2008. In addition to the continuous coverage by Fermi, contemporaneous observations were carried out from the radio to γ-ray bands between 2008 September and 2009 February. In this paper, we summarize the rich multi-wavelength data collected during the campaign (including F-GAMMA, GASP-WEBT, Kanata, OVRO, RXTE, SMARTS, Swift, and other instruments), examine the cross-correlation between the light curves measured in the different energy bands, and interpret the resulting spectral energy distributions in the context of well-known blazar emission models. We find that the γ-ray activity is well correlated with a series of near-IR/optical flares, accompanied by an increase in the optical polarization degree. On the other hand, the X-ray light curve shows a distinct 20 day high state of unusually soft spectrum, which does not match the extrapolation of the optical/UV synchrotron spectrum. We tentatively interpret this feature as the bulk Compton emission by cold electrons contained in the jet, which requires an accretion disk corona with an effective covering factor of 19% at a distance of 100 R g. We model the broadband spectra with a leptonic model with external radiation dominated by the infrared emission from the dusty torus. © 2012. The American Astronomical Society. All rights reserved
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Environmental overview of geothermal development: northern Nevada
Regional environmental problems and issues associated with geothermal development in northern Nevada are studied to facilitate environmental assessment of potential geothermal resources. The various issues discussed are: environmental geology, seismicity of northern Nevada, hydrology and water quality, air quality, Nevada ecosystems, noise effects, socio-economic impacts, and cultural resources and archeological values. (MHR
Community knowledge and beliefs about ADHD
Accurate knowledge and positive attitudes within the community are important for the effective diagnosis, treatment and support of people with ADHD. Most previous research about knowledge and attitudes has focused only on professional groups and parents of children with ADHD. The aim of this study was to explore knowledge about ADHD characteristics and causes, and attitudes towards issues such as medication in the general population. Six hundred and forty-five members of the Australian community, all of whom were parents, completed a questionnaire. The findings showed that the core features of ADHD were well-known, but there were misconceptions and considerable uncertainty about many aspects. Most respondents failed to recognise the genetic basis of the disorder and its potentially lifelong nature. Fathers were less knowledgeable than mothers. Although most participants believed that ADHD is a genuine disorder and recognised the benefits of medication, the majority believed that it is diagnosed too frequently and that medication is prescribed too readily. The study concluded that, in many respects, the public is not well-informed about ADHD and suggested that the media may have an important role in enhancing community awareness of the disorder through responsible, sensitive and accurate reporting
Antigenic Drift of the Pandemic 2009 A(H1N1) Influenza Virus in a Ferret Model
10.1371/journal.ppat.1003354PLoS Pathogens95e100335
The Effect of Impact Damage on the Room-Temperature Fatigue Behavior of γ-TiAl
The relationship between impact damage and the fatigue behavior of γ-TiAl has been examined. Axial fatigue specimens fabricated from cast Ti-47.9Al-2.0Cr-1.9Nb (to be referred to as 48-2-2) and Ti-47.3Al-2.2Nb-0.5Mn-0.4W-0.4Mo-0.23Si (to be referred to as WMS) alloys were damaged by impact under controlled conditions with a 60 deg wedge-shaped indenter to simulate assembly-related damage in low-pressure turbine blades. The level of damage produced was quantified and found to correlate well with the peak load of the impact event. The WMS alloy exhibited a greater resistance to impact damage due to its higher yield strength and lamellar microstructure. A measure of the ambient-temperature fatigue failure stress in the alloys was obtained by standard fatigue testing employing a step-loading approach. The failure stress of the WMS alloy was greater than that of the 48-2-2 alloy in the undamaged state. The relationship between impact damage and failure stress was examined using a threshold-based approach. These studies indicate that, for damage levels below a transitional flaw size, the failure stress is near that for undamaged specimens. At damage levels greater than the transitional flaw size, the failure stress can be adequately approximated using the threshold stress-intensity range (ΔKTH ) from long-crack growth testing. Fractographic studies were performed to investigate impact damage and crack-advance mechanisms, which match those observed in other alloys tested at room temperature
Estimating the Fitness Advantage Conferred by Permissive Neuraminidase Mutations in Recent Oseltamivir-Resistant A(H1N1)pdm09 Influenza Viruses
10.1371/journal.ppat.1004065PLoS Pathogens104e100406