22,522 research outputs found
Conodont biostratigraphy of the Crawford Group, Southern Uplands, Scotland
Extensive new conodont collections from the Crawford Group, the oldest succession in the Southern Uplands of Scotland, support the previously documented biostratigraphical ages for the included formations. The Raven Gill Formation is lower Whitlandian, Arenig (comparable in age to the Dounans Limestone in the Highland Border Complex) and the Kirkton Formation is latest Llandeilian-Aurelucian, Llanvirn to Caradoc in age. It is concluded that there is a significant stratigraphical gap within the Crawford Group. The restricted and probably fault-bounded nature of the Raven Gill outcrops suggests that these may represent olistoliths within a mélange of Llandeilian-Aurelucian age. The chert-bearing succession of the Northern Belt of the Southern Uplands thus represents the juxtaposed sedimentary records of two entirely separate basins – the oldest pre-dates the Grampian assembly of the Laurentian margin, and the younger, the Northern Belt Basin sensu stricto, entirely post-dates this event
Mitigating the risk of Zika virus contamination of raw materials and cell lines in the manufacture of biologicals
Ensuring the virological safety of biologicals is challenging due to the risk of viral contamination of raw materials and cell
banks, and exposure during in-process handling to known and/or emerging viral pathogens. Viruses may contaminate raw
materials and biologicals intended for human or veterinary use and remain undetected until appropriate testing measures
are employed. The outbreak and expansive spread of the mosquito-borne flavivirus Zika virus (ZIKV) poses challenges to
screening human- and animal -derived products used in the manufacture of biologicals. Here, we report the results of an in
vitro study where detector cell lines were challenged with African and Asian lineages of ZIKV. We demonstrate that this
pathogen is robustly detectable by in vitro assay, thereby providing assurance of detection of ZIKV, and in turn underpinning
the robustness of in vitro virology assays in safety testing of biologicals
An Interesting Charmonium State Formation and Decay :
Massless perturbative QCD forbids, at leading order, the exclusive
annihilation of proton-antiproton into some charmonium states, which, however,
have been observed in the channel, indicating the significance of
higher order and non perturbative effects in the few GeV energy region. The
most well known cases are those of the () and the . The
case of the is considered here and a way of detecting such a state
through its typical angular distribution in the radiative decay
is suggested. Estimates of the branching ratio , as given by a quark-diquark model of the nucleon, mass corrections
and an instanton induced process are presented.Comment: 9 pages (no figures), Plain TeX, CBPF-NF-014/94, INFNCA-TH-94-
First hospital outbreak of the globally emerging Candida auris in a European hospital
Background: Candida auris is a globally emerging multidrug resistant fungal pathogen causing nosocomial transmission. We report an ongoing outbreak of C. auris in a London cardio-thoracic center between April 2015 and July 2016. This is the first report of C. auris in Europe and the largest outbreak so far. We describe the identification, investigation and implementation of control measures. Methods: Data on C. auris case demographics, environmental screening, implementation of infection prevention/control measures, and antifungal susceptibility of patient isolates were prospectively recorded then analysed retrospectively. Speciation of C. auris was performed by MALDI-TOF and typing of outbreak isolates performed by amplified fragment length polymorphism (AFLP). Results: This report describes an ongoing outbreak of 50 C. auris cases over the first 16 month (April 2015 to July 2016) within a single Hospital Trust in London. A total of 44 % (n = 22/50) patients developed possible or proven C. auris infection with a candidaemia rate of 18 % (n = 9/50). Environmental sampling showed persistent presence of the yeast around bed space areas. Implementation of strict infection and prevention control measures included: isolation of cases and their contacts, wearing of personal protective clothing by health care workers, screening of patients on affected wards, skin decontamination with chlorhexidine, environmental cleaning with chorine based reagents and hydrogen peroxide vapour. Genotyping with AFLP demonstrated that C. auris isolates from the same geographic region clustered. Conclusion: This ongoing outbreak with genotypically closely related C. auris highlights the importance of appropriate species identification and rapid detection of cases in order to contain hospital acquired transmission
Reading Guide 7: Intervention strategies and business case
Earthworks deteriorate over time and are additionally subject to increasingly extreme weather conditions. A range of intervention types is available to maintain the safety and serviceability of earthworks assets, and these should be selected and made as cost-effectively as possible, to maximise asset condition improvement within the available budget
Selenium and tellurium concentrations of Carboniferous British coals
The authors wish to thank Kier Group, the British Coal Utilisation Research Association (BCURA) and Uniper (E.On) for kindly providing coal samples. The authors are grateful to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), and Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) for supporting this study. The authors are grateful for the thorough and constructive comments from two anonymous reviewers, as well as the careful editorial handling of Prof. Ian Somerville. This work was supported by the NERC under Grant number NE/L001764/1.Peer reviewedPublisher PD
A penalized framework for distributed lag non-linear models.
: Distributed lag non-linear models (DLNMs) are a modelling tool for describing potentially non-linear and delayed dependencies. Here, we illustrate an extension of the DLNM framework through the use of penalized splines within generalized additive models (GAM). This extension offers built-in model selection procedures and the possibility of accommodating assumptions on the shape of the lag structure through specific penalties. In addition, this framework includes, as special cases, simpler models previously proposed for linear relationships (DLMs). Alternative versions of penalized DLNMs are compared with each other and with the standard unpenalized version in a simulation study. Results show that this penalized extension to the DLNM class provides greater flexibility and improved inferential properties. The framework exploits recent theoretical developments of GAMs and is implemented using efficient routines within freely available software. Real-data applications are illustrated through two reproducible examples in time series and survival analysis.<br/
Modeling the impact of zooplankton diel vertical migration on the carbon export flux of the biological pump
Author Posting. © American Geophysical Union, 2010. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 33(2), (2019): 181-199. doi:10.1029/2018GB005983.One pathway of the biological pump that remains largely unquantified in many export models is the active transport of carbon from the surface ocean to the mesopelagic by zooplankton diel vertical migration (DVM). Here, we develop a simple representation of zooplankton DVM and implement it in a global export model as a thought experiment to illustrate the effects of DVM on carbon export and mesopelagic biogeochemistry. The model is driven by diagnostic satellite measurements of net primary production, algal biomass, and phytoplankton size structure. Due to constraints on available satellite data, the results are restricted to the latitude range from 60°N to 60°S. The modeled global export flux from the base of the euphotic zone was 6.5 PgC/year, which represents a 14% increase over the export flux in model runs without DVM. The mean (± standard deviation, SD) proportional contribution of the DVM‐mediated export flux to total carbon export, averaged over the global domain and the climatological seasonal cycle, was 0.16 ± 0.04 and the proportional contribution of DVM activity to total respiration within the twilight zone was 0.16 ± 0.06. Adding DVM activity to the model also resulted in a deep local maximum in the oxygen utilization profile. The model results were most sensitive to the assumptions for the fraction of individuals participating in DVM, the fraction of fecal pellets produced in the euphotic zone, and the fraction of grazed carbon that is metabolized.Support for this work came from the National Science Foundation (OCE‐1434000 and OCE‐1657803) and the National Aeronautics and Space Administration (NASA) as part of the EXport Processes in the global Ocean from RemoTe Sensing (EXPORTS) field campaign (grant 80NSSC17K0692) and the North Atlantic Aerosol and Marine Ecosystems Study (NAAMES, grants NNX15AE72G and 80NSSC18K0018). The satellite data used as drivers for the model are available as supporting information. The World Ocean Atlas data (World Ocean Atlas 2009, Annual Climatology, 1 degree, Temperature, Salinity, Oxygen) containing temperature and oxygen measurements can be downloaded from the ERDAPP data server (https://coastwatch.pfeg.noaa.gov/erddap/index.html).2019-07-1
Cooled propylene glycol as a pragmatic choice for preservation of DNA from remote field-collected Diptera for next-generation sequence analysis
Next-generation sequencing (NGS)-based methods can now be applied to large population-scale studies, but this demands very high-quality DNA. For specimens collected from remote field locations, DNA degradation can be a problem, requiring logistically challenging preservation techniques. Simpler preservation techniques are therefore required. Prior to collection of exotic fruit fly (Tephritidae) species, a number of readily available preservatives with storage at either 4°C or room temperature were trialed here to determine the DNA quality for three locally available Diptera species,Fannia canicularis(L.),Musca domesticaL., and Lucilia sericataMeigen. Considerable variation was observed between the different preservatives, species, and temperatures, but several preservatives at 4°C were favored. Chilled propylene glycol was subsequently used for the storage and carriage of Australian field-collectedBactrocera fruit fly specimens to New Zealand. When processed up to 20 d later, DNA fragments of ∼10-20 kb were obtained for successful genotyping by sequencing analysis. This protocol is therefore recommended as a logistically simple and safe approach for distant collection of dipteran samples for NGS population genomic studies
Electromagnetic and corpuscular emission from the solar flare of 1991 June 15: Continuous acceleraton of relativistic particles
Data on X-,γ-ray, optical and radio emission from the 1991 June 15 solar flare are considered. We have calculated the spectrum of protons that producesγ-rays during the gradual phase of the flare. The primary proton spectrum can be described as a Bessel-function-type up to 0.8 GeV and a power law with the spectral index ≈3 from 0.8 up to 10 GeV or above. We have also analyzed data on energetic particles near the Earth. Their spectrum differed from that of primary protons producingγ-ray line emission. In the gradual phase of the flare additional pulses of energy release occurred and the time profiles of cm-radio emission andγ-rays in the 0.8–10 MeV energy band and above 50 MeV coincided. A continuous and simultaneous stochastic acceleration of the protons and relativistic electrons at the gradual phase of the flare is considered as a natural explanation of the data
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