876 research outputs found

    The Hudson Bay Lithospheric Experiment (HuBLE) : Insights into Precambrian Plate Tectonics and the Development of Mantle Keels

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    The UK component of HuBLE was supported by Natural Environment Research Council (NERC) grant NE/F007337/1, with financial and logistical support from the Geological Survey of Canada, Canada–Nunavut Geoscience Office, SEIS-UK (the seismic node of NERC), and First Nations communities of Nunavut. J. Beauchesne and J. Kendall provided invaluable assistance in the field. Discussions with M. St-Onge, T. Skulski, D. Corrigan and M. Sanborne-Barrie were helpful for interpretation of the data. D. Eaton and F. A. Darbyshire acknowledge the Natural Sciences and Engineering Research Council. Four stations on the Belcher Islands and northern Quebec were installed by the University of Western Ontario and funded through a grant to D. Eaton (UWO Academic Development Fund). I. Bastow is funded by the Leverhulme Trust. This is Natural Resources Canada Contribution 20130084 to its Geomapping for Energy and Minerals Program. This work has received funding from the European Research Council under the European Unions Seventh Framework Programme (FP7/2007-2013)/ERC Grant agreement no. 240473 ‘CoMITAC’.Peer reviewedPublisher PD

    Virtual drug round: Development and next steps

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    Internationally, nurses are responsible for the accurate administration of drugs to patients in their care, something that is vital to maintaining the safety and well-being of patients. Whilst educational input to drug administration is provided, there remain a high number of errors in medicine calculations and delivery. To address these areas of concern different approaches to the development of knowledge and skills in medicine administration are being explored. This paper discusses the development and proposed implementation of a virtual drug round (VDR) in a University in the United Kingdom that aims to support the safe administration of medicines. It reflects on the processes of developing the VDR in some detail and considers the implementation plan. Proposals for evaluation are also considered that will inform ongoing development and transferabilit

    Virtual drug round: Development and next steps

    Get PDF
    Internationally, nurses are responsible for the accurate administration of drugs to patients in their care, something that is vital to maintaining the safety and well-being of patients. Whilst educational input to drug administration is provided, there remain a high number of errors in medicine calculations and delivery. To address these areas of concern different approaches to the development of knowledge and skills in medicine administration are being explored. This paper discusses the development and proposed implementation of a virtual drug round (VDR) in a University in the United Kingdom that aims to support the safe administration of medicines. It reflects on the processes of developing the VDR in some detail and considers the implementation plan. Proposals for evaluation are also considered that will inform ongoing development and transferabilit

    Characterization of the DNA polymerases induced by a group of herpes simplex virus type I variants selected for growth in the presence of phosphonoformic acid

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    Five independently derived variants of a herpes simplex virus type I (HSV-1) strain were plaque purified from a virus population passaged in 1 mM phosphonoformic acid (PFA). The DNA polymerase induced by the parent and PFA-resistant viruses were purified and characterized. No differences were observed among the enzymes with respect to their chromatographic properties, specific activities, or polypeptides resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The variant enzymes exhibited levels of PFA resistance which ranged from 15- to 25-fold. Resistance to PFA was always associated with a similar degree of resistance to its congener phosphonoacetic acid, but cross-resistance to beta-phenylphosphonoacetic acid was only seen with two of the five variant enzymes. PFA and pyrophosphate were mutually competitive in PPi exchange reactions, but in DNA synthetic reactions the levels of resistance to PFA and PPi were not equal. The apparent affinities of the enzymes for Mg2+ did parallel their affinities for PFA. Km values of dNTPs were about 2-fold higher than the parent virus enzyme for all of the variant enzymes except one which was 4-fold higher. The processivity of polymerization was apparently unaffected by the enzyme changes related to PFA resistance although one variant enzyme had a lower value. Resistance among the variant enzymes to the triphosphates of 9-(2-hydroxyethoxymethyl)guanine and 2',3'-dideoxyguanosine was directly related to the level of resistance to PFA. The data presented here indicated that (i) PFA resistance may result from several types of active site alterations, since the PFA-resistant enzymes were of three kinetically distinct types. Also, additional enzyme alterations, probably unrelated to PFA resistance, were detected in one enzyme. (ii) PFA and PPi possess some different binding determinants within the active center of herpes simplex virus type I DNA polymerase. (iii) PFA and the triphosphates of 9-(2-hydroxyethoxymethyl)guanine and 2',3'-dideoxyguanosine may have a common ultimate inhibitory mechanism

    Cytotoxic Action of Carboxyborane Heterocyclic Amine Adducts

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    The heterocyclic carboxyborane amines were found to be potent cytotoxic agents in the murine L1210 lymphoid leukemia and human HeLa suspended carcinoma cells. These agents were observed to inhibit HeLa DNA topoisomerase II activity ~ 200 μM and L1210 topoisomerase II activity ≥ 100 μM. These agents did not cause DNA protein linked breaks themselves, but upon incubation for 14-24 hr did enhance the ability of VP-16 to cause cleavable complexes. The heterocyclic amineboranes inhibited DNA synthesis and caused DNA strand scission. They were additive with VP-16 in affording these results as well as inhibiting colony growth of L1210 cells after co-incubation for 1 hr. The agents inhibited in vitro PKC phosphorylation of both L1210 lymphoid leukemia and human topoisomerase II enzyme

    A Meta-Analysis Of Resource Pulse-Consumer Interactions

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    Resource Pulses are infrequent, large-magnitude, and short-duration events of increased resource availability. They include a diverse set of extreme events in a wide range of ecosystems, but identifying general patterns among the diversity of pulsed resource phenomena in nature remains an important challenge. Here we present a meta-analysis of resource pulse-consumer interactions that addresses four key questions: (1) Which characteristics of pulsed resources best predict their effects on consumers? (2) Which characteristics of consumers best predict their responses to resource pulses? (3) How do the effects of resource Pulses differ in different ecosystems? (4) What are the indirect effects of resource pulses in communities\u27? To investigate these questions, we built a data set of diverse Pulsed resource-consumer interactions from around the world, developed metrics to compare the effects of resource pulses across disparate systems, and conducted multilevel regression analyses to examine the manner in which variation in the characteristics of resource pulse-consumer interactions affects important aspects Of Consumer responses. Resource pulse magnitude, resource trophic level, resource Pulse duration, ecosystem type and subtype, consumer response mechanisms, and consumer body mass were found to be key. explanatory factors predicting the magnitude, duration, and timing of consumer responses. Larger consumers showed more persistent responses to resource pulses, and reproductive responses were more persistent than aggregative responses. Aquatic systems showed shorter temporal lags between peaks of resource availability and consumer response compared to terrestrial systems, and temporal lags were also shorter for smaller consumers compared to larger consumers. The magnitude of consumer responses relative to their resource pulses was generally smaller for the direct consumers of primary resource pulses, compared to consumers at greater trophic distances from the initial resource pulse. In specific systems, this data set showed both attenuating and amplifying indirect effects. We consider the mechanistic processes behind these patterns and their implications for the ecology of resource pulses

    Subduction beneath Laurentia modified the eastern North American cratonic edge : Evidence from P wave and S wave tomography

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    Funding Information: NERC Doctoral Training Partnership: Science and Solutions for a Changing Planet and Leverhulme Trust Acknowledgments A.B. is funded by the NERC Doctoral Training Partnership: Science and Solutions for a Changing Planet. I.B. is funded by the Leverhulme Trust. F.D. acknowledges funding from NSERC through their Discovery grants and Canada Research Chairs program. We thank J. VanDecar for use of his tomographic inversion and MCCC codes. SAC [Helffrich et al., 2013] and GMT [Wessel and Smith, 1995] software were also used to process seismic data obtained from the IRIS DMC and from the Canadian National Data Centre (Natural Resources Canada). A digital supplement is also available to download containing models and the processed relative arrival‐time data set, additional information is available from A.B. (email: [email protected]). Discussing the implications of our tomographic results with S. Goes and A. Hynes provided great motivation for this manuscript. Two anonymous reviewers helped clarify our interpretations.Peer reviewedPublisher PD

    Seismicity and crustal structure of the southern main Ethiopian rift: new evidence from Lake Abaya

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    The Main Ethiopian Rift (MER) has developed during the 18 Ma-Recent separation of the Nubian and Somalian plates. Extension in its central and northern sectors is associated with seismic activity and active magma intrusion, primarily within the rift, where shallow (urn:x-wiley:15252027:media:ggge22586:ggge22586-math-00015 km) seismicity along magmatic centers is commonly caused by fluid flow through open fractures in hydrothermal systems. However, the extent to which similar magmatic rifting persists into the southern MER is unknown. Using data from a temporary network of five seismograph stations, we analyze patterns of seismicity and crustal structure in the Abaya region of the southern MER. Magnitudes range from 0.9 to 4.0; earthquake depths are 0–30 km. urn:x-wiley:15252027:media:ggge22586:ggge22586-math-0002 ratios of urn:x-wiley:15252027:media:ggge22586:ggge22586-math-00031.69, estimated from Wadati diagram analysis, corroborate bulk-crustal urn:x-wiley:15252027:media:ggge22586:ggge22586-math-0004 ratios determined via teleseismic P-to-S receiver function H-urn:x-wiley:15252027:media:ggge22586:ggge22586-math-0005 stacking and reveal a relative lack of mafic intrusion compared to the MER rift sectors to the north. There is a clear association of seismicity with the western border fault system of the MER everywhere in our study area, but earthquake depths are shallow near Duguna volcano, implying a shallowed geothermal gradient associated with rift valley silicic magmatism. This part of the MER is thus interpreted best as a young magmatic system that locally impacts the geothermal gradient but that has not yet significantly modified continental crustal composition via rift-axial magmatic rifting

    Susceptibility of phosphonoformic acid-resistant herpes simplex virus variants to arabinosylnucleosides and aphidicolin.

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    A plaque-reduction assay was used to examine the susceptibility of five phosphonoformic acid-resistant variants of herpes simplex virus type 1 to arabinosylnucleosides and aphidicolin. These viruses were cross-resistant to arabinosylhypoxanthine and to arabinosyladenine when tested in the absence of deoxycoformycin, a deaminase inhibitor. In the presence of deoxycoformycin, no cross-resistance between arabinosyladenine and phosphonoformic acid was observed. The two variants tested were cross-resistant to arabinosylthymine, and all five variants were collaterally susceptible to aphidicolin inhibition
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