593 research outputs found
Distinguishing low frequency mutations from RT-PCR and sequence errors in viral deep sequencing data
There is a high prevalence of coronary artery disease (CAD) in patients with left bundle branch block (LBBB); however there are many other causes for this electrocardiographic abnormality. Non-invasive assessment of these patients remains difficult, and all commonly used modalities exhibit several drawbacks. This often leads to these patients undergoing invasive coronary angiography which may not have been necessary. In this review, we examine the uses and limitations of commonly performed non-invasive tests for diagnosis of CAD in patients with LBBB
Genetic and antigenic characterisation of serotype A FMD viruses from East Africa to select new vaccine strains
Vaccine strain selection for emerging foot-and-mouth disease virus (FMDV) outbreaks in enzootic countries can be addressed through antigenic and genetic characterisation of recently circulating viruses. A total of 56 serotype A FMDVs isolated between 1998 and 2012, from Central, East and North African countries were characterised antigenically by virus neutralisation test using antisera to three existing and four candidate vaccine strains and, genetically by characterising the full capsid sequence data. A Bayesian analysis of the capsid sequence data revealed the viruses to be of either African or Asian topotypes with subdivision of the African topotype viruses into four genotypes (Genotypes I, II, IV and VII). The existing vaccine strains were found to be least cross-reactive (good matches observed for only 5.4â46.4% of the sampled viruses). Three bovine antisera, raised against A-EA-2007, A-EA-1981 and A-EA-1984 viruses, exhibited broad cross-neutralisation, towards more than 85% of the circulating viruses. Of the three vaccines, A-EA-2007 was the best showing more than 90% in-vitro cross-protection, as well as being the most recent amongst the vaccine strains used in this study. It therefore appears antigenically suitable as a vaccine strain to be used in the region in FMD control programmes
Normal variation in thermal radiated temperature in cattle: implications for foot-and-mouth disease detection
<p>Abstract</p> <p>Background</p> <p>Thermal imagers have been used in a number of disciplines to record animal surface temperatures and as a result detect temperature distributions and abnormalities requiring a particular course of action. Some work, with animals infected with foot-and-mouth disease virus, has suggested that the technique might be used to identify animals in the early stages of disease. In this study, images of 19 healthy cattle have been taken over an extended period to determine hoof and especially coronary band temperatures (a common site for the development of FMD lesions) and eye temperatures (as a surrogate for core body temperature) and to examine how these vary with time and ambient conditions.</p> <p>Results</p> <p>The results showed that under UK conditions an animal's hoof temperature varied from 10°C to 36°C and was primarily influenced by the ambient temperature and the animal's activity immediately prior to measurement. Eye temperatures were not affected by ambient temperature and are a useful indicator of core body temperature.</p> <p>Conclusions</p> <p>Given the variation in temperature of the hooves of normal animals under various environmental conditions the use of a single threshold hoof temperature will be at best a modest predictive indicator of early FMD, even if ambient temperature is factored into the evaluation.</p
Chandra X-Ray Spectroscopy Of The Very Early O Supergiant HD 93129A: Constraints On Wind Shocks And The Mass-Loss Rate
We present an analysis of both the resolved X-ray emission-line profiles and the broad-band X-ray spectrum of the O-2 If* star HD 93129A, measured with the Chandra High Energy Transmission Grating Spectrometer ( HETGS). This star is among the earliest and most massive stars in the Galaxy, and provides a test of the embedded wind-shock scenario in a very dense and powerful wind. A major new result is that continuum absorption by the dense wind is the primary cause of the hardness of the observed X-ray spectrum, while intrinsically hard emission from colliding wind shocks contributes less than 10 per cent of the X-ray flux. We find results consistent with the predictions of numerical simulations of the line-driving instability, including line broadening indicating an onset radius of X-ray emission of several tenths of R-*. Helium-like forbidden-to-intercombination line ratios are consistent with this onset radius, and inconsistent with being formed in a wind-collision interface with the star\u27s closest visual companion at a distance of 100 au. The broad-band X-ray spectrum is fitted with a dominant emission temperature of just kT = 0.6 keV along with significant wind absorption. The broad-band wind absorption and the line profiles provide two independent measurements of the wind mass-loss rate:. M = 5.2(-1.5)(+1.8) x 10(-6) and 6.8(-2.2)(+2.8) x 10(-6) M-circle dot yr(-1), respectively. This is the first consistent modelling of the X-ray line-profile shapes and broad-band X-ray spectral energy distribution in a massive star, and represents a reduction of a factor of 3-4 compared to the standard H alpha mass-loss rate that assumes a smooth wind
A revised position for the rotated Falkland Islands microplate
The early stages of transform margin formation are associated with crustal fragmentation and block rotation. The restricted size of the resultant microcontinental blocks precludes palaeogeographical reconstructions and reliable estimations of the amount of rotation they can undergo. An example considered here is the Falkland Plateau. This is located adjacent to the AgulhasâFalkland Fracture Zone and its westernmost province is the Falkland Islands microcontinent. The position of the plateau and the islands prior to Gondwana break-up remains contentious. This study integrates seismic reflection and gravity data to propose a revised position of the Falkland Islands microcontinent constrained by (1) the presence of a mega-dĂ©collement, controlling the Gondwanide Orogen, described north of the Falkland Islands and underneath South Africa and the Outeniqua Basin, and (2) the similar architecture of fault networks mapped north of the islands and in the northernmost Outeniqua Basin. This revised position requires a re-evaluation of the timing and rate of rotation of the Falkland Islands microcontinent and affects the expected crustal architecture adjacent to the islands. Our model yields rotation rates between 5.5° and 8°â
Maâ1 and two potential times for rotation, and predicts more unstretched crust beneath the basin east of the Falkland Islands than previous model
New species of Asclepias (Apocynaceae), Baphia (Leguminosae), Cochlospermum (Bixaceae) and Endostemon (Lamiaceae) from the Kalahari sands of Angola and NW Zambia, with one new combination in Vangueria (Rubiaceae)
Four new species are described from central and eastern Angola and adjacent NW Zambia. All occur in Kalahari sand savannas rich in endemic and more widely distributed geoxylic suffrutices. Despite being known from very few collections, the conservation status of one of these new species is assessed as Least Concern, as these grasslands are nutrient-poor, are in remote sparsely populated areas, and are not threatened with conversion to agriculture. The remaining three are treated as Data Deficient. In addition, one new combination is provided for Ancylanthos rubiginosus Desf. under Vangueria as V. rubiginosa (Desf.) Lantz is an illegitimate later homonym. We also make orthographic corrections to specific epithets commemorating Ilse von Nolde, a collector who made important collections from Quela in Malange in the 1930s
Beyond the consensus: dissecting within-host viral population diversity of foot-and-mouth disease virus using next-generation genome sequencing
The sequence diversity of viral populations within individual hosts is the
starting material for selection and subsequent evolution of RNA viruses such as
foot-and-mouth disease virus (FMDV). Using next-generation sequencing (NGS)
performed on a Genome Analyzer platform (Illumina), this study compared the
viral populations within two bovine epithelial samples (foot lesions) from a
single animal with the Inoculum used to initiate experimental infection.
Genomic sequences were determined in duplicate sequencing runs, and the
consensus sequence determined by NGS, for the Inoculum, was identical to that
previously determined using the Sanger method. However, NGS reveals the fine
polymorphic sub-structure of the viral population, from nucleotide variants
present at just below 50% frequency to those present at fractions of 1%. Some
of the higher frequency polymorphisms identified encoded changes within codons
associated with heparan sulphate binding and were present in both feet lesions
revealing intermediate stages in the evolution of a tissue-culture adapted
virus replicating within a mammalian host. We identified 2,622, 1,434 and 1,703
polymorphisms in the Inoculum, and in the two foot lesions respectively: most
of the substitutions occurred only in a small fraction of the population and
represent the progeny from recent cellular replication prior to onset of any
selective pressures. We estimated an upper limit for the genome-wide mutation
rate of the virus within a cell to be 7.8 x 10-4 per nt. The greater depth of
detection, achieved by NGS, demonstrates that this method is a powerful and
valuable tool for the dissection of FMDV populations within-hosts
The pneumococcal alpha-glycerophosphate oxidase enhances nasopharyngeal colonization through binding to host glycoconjugates
Streptococcus pneumoniae (the pneumococcus) is a major human pathogen, causing a broad spectrum of diseases including otitis media, pneumonia, bacteraemia and meningitis. Here we examined the role of a potential pneumococcal meningitis vaccine antigen, alpha-glycerophosphate oxidase (SpGlpO), in nasopharyngeal colonization. We found that serotype 4 and serotype 6A strains deficient in SpGlpO have significantly reduced capacity to colonize the nasopharynx of mice, and were significantly defective in adherence to human nasopharyngeal carcinoma cells in vitro. We also demonstrate that intranasal immunization with recombinant SpGlpO significantly protects mice against subsequent nasal colonization by wild type serotype 4 and serotype 6A strains. Furthermore, we show that SpGlpO binds strongly to lacto/neolacto/ganglio host glycan structures containing the GlcNAcÎČ1-3GalÎČ disaccharide, suggesting that SpGlpO enhances colonization of the nasopharynx through its binding to host glycoconjugates. We propose that SpGlpO is a promising vaccine candidate against pneumococcal carriage, and warrants inclusion in a multi-component protein vaccine formulation that can provide robust, serotype-independent protection against all forms of pneumococcal disease
The role of sand lances (Ammodytes sp.) in the Northwest Atlantic ecosystem: a synthesis of current knowledge with implications for conservation and management
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Staudinger, M. D., Goyert, H., Suca, J. J., Coleman, K., Welch, L., Llopiz, J. K., Wiley, D., Altman, I., Applegate, A., Auster, P., Baumann, H., Beaty, J., Boelke, D., Kaufman, L., Loring, P., Moxley, J., Paton, S., Powers, K., Richardson, D., Robbins, J., Runge, J., Smith, B., Spiegel, C., & Steinmetz, H. The role of sand lances (Ammodytes sp.) in the Northwest Atlantic ecosystem: a synthesis of current knowledge with implications for conservation and management. Fish and Fisheries, 00, (2020): 1-34, doi:10.1111/faf.12445.The American sand lance (Ammodytes americanus, Ammodytidae) and the Northern sand lance (A. dubius, Ammodytidae) are small forage fishes that play an important functional role in the Northwest Atlantic Ocean (NWA). The NWA is a highly dynamic ecosystem currently facing increased risks from climate change, fishing and energy development. We need a better understanding of the biology, population dynamics and ecosystem role of Ammodytes to inform relevant management, climate adaptation and conservation efforts. To meet this need, we synthesized available data on the (a) life history, behaviour and distribution; (b) trophic ecology; (c) threats and vulnerabilities; and (d) ecosystem services role of Ammodytes in the NWA. Overall, 72 regional predators including 45 species of fishes, two squids, 16 seabirds and nine marine mammals were found to consume Ammodytes. Priority research needs identified during this effort include basic information on the patterns and drivers in abundance and distribution of Ammodytes, improved assessments of reproductive biology schedules and investigations of regional sensitivity and resilience to climate change, fishing and habitat disturbance. Food web studies are also needed to evaluate trophic linkages and to assess the consequences of inconsistent zooplankton prey and predator fields on energy flow within the NWA ecosystem. Synthesis results represent the first comprehensive assessment of Ammodytes in the NWA and are intended to inform new research and support regional ecosystemâbased management approaches.This manuscript is the result of followâup work stemming from a working group formed at a twoâday multidisciplinary and international workshop held at the Parker River National Wildlife Refuge, Massachusetts in May 2017, which convened 55 experts scientists, natural resource managers and conservation practitioners from 15 state, federal, academic and nonâgovernmental organizations with interest and expertise in Ammodytes ecology. Support for this effort was provided by USFWS, NOAA Stellwagen Bank National Marine Sanctuary, U.S. Department of the Interior, U.S. Geological Survey, Northeast Climate Adaptation Science Center (Award # G16AC00237), an NSF Graduate Research Fellowship to J.J.S., a CINAR Fellow Award to J.K.L. under Cooperative Agreement NA14OAR4320158, NSF award OCEâ1325451 to J.K.L., NSF award OCEâ1459087 to J.A.R, a Regional Sea Grant award to H.B. (RNE16âCTHCEâl), a National Marine Sanctuary Foundation award to P.J.A. (18â08âBâ196) and grants from the Mudge Foundation. The contents of this paper are the responsibility of the authors and do not necessarily represent the views of the National Oceanographic and Atmospheric Administration, U.S. Fish and Wildlife Service, New England Fishery Management Council and MidâAtlantic Fishery Management Council. This manuscript is submitted for publication with the understanding that the United States Government is authorized to reproduce and distribute reprints for Governmental purposes. Any use of trade, firm or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government
Tsunami awareness and preparedness in Aotearoa New Zealand:The evolution of community understanding
After catastrophic events such as the 2004 Indian Ocean tsunami and the 2011 Great East Japan earthquake and tsunami there is a clear need for vulnerable countries like Aotearoa New Zealand to get prepared for tsunami. In the last ten years, the New Zealand government initiated major efforts to raise awareness of tsunami risk among coastal residents. This study explores tsunami awareness, preparedness, and evacuation intentions among residents of the East Coast of the North Island in a 2015 survey. The ten chosen locations also participated in a tsunami survey in 2003, with results demonstrating that tsunami awareness rose in the twelve years between the surveys. The 2015 survey also included questions on preparedness and intended action. Even though coastal residents know they live in a tsunami prone area, preparedness is relatively low and high expectations of a formal warning remain, even for a local source tsunami scenario. Furthermore, survey respondents had unrealistic ideas of evacuation procedures. When asked about their evacuation intentions, respondents intended to undertake a number of different actions before evacuating their homes, which could cause significant delays in the evacuation process. Most respondents were also reluctant to evacuate on foot and prefer using their vehicles instead, which could create dangerous traffic congestion. These surveyed intentions are consistent with a study of actual evacuation behaviours in the subsequent 2016 KaikĆura earthquake and tsunami, providing validation for the survey indicators. This paper identifies the procedures least understood by the public and offers some solutions to improve tsunami preparedness.</p
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