2,168 research outputs found
Exploratory talk within collaborative small groups in mathematics
No full textThis report describes one aspect of a wider research study on exploratory talk within collaborative small groups in secondary mathematics lessons. It outlines students’ views of using collaborative activity to learn mathematics. The fuller research study explores the extent to which exploratory talk occurs in collaborative peer groups in secondary mathematics classrooms
Paul Edwards
No full textPaul Edwards was an author in the Utah Historical Quarterly in the Fall 1973 edition, Vol 41
Russell–Silver syndrome presenting as early asymmetric IUGR
No full textWe report a case of severe intrauterine growth restriction (IUGR) which was diagnosed as Russell–Silver syndrome (RSS) postnatally. RSS (also known as Silver–Russell syndrome) is one of more than 300 recognised forms of genetic disorder that leads to short stature. Uniparental disomy for chromosome 7 (UPD7), i.e. inheriting two copies of chromosome 7 from the mother, and a change in methylation pattern (biochemical silencing of gene expression) of chromosome 11 are the most frequently associated chromosomal defects. A wide spectrum of appearances and symptoms are associated with the condition. Most characteristics are not easily identifiable with prenatal diagnostic ultrasound. The symptom most likely to be detected sonographically is IUGR. This case seeks to raise awareness of RSS, and encourages clinicians to consider uncommon genetic disorders such as RSS as a possible cause of early asymmetric IUGR. ABSTRACT FROM AUTHOR]; Copyright of Ultrasound is the property of Royal Society of Medicine Press Limited and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)32572957Source type: Electronic(1
Barley plants overexpressing ferrochelatases (HvFC1 and HvFC2) show improved photosynthetic rates and have reduced photo-oxidative damage under drought stress than non-transgenic controls
No full textWe investigated the roles of two Ferrochelatases (FCs), which encode the terminal enzyme for heme biosynthesis, in drought and oxidative stress tolerance in model cereal plant barley (Hordeum vulgare). Three independent transgenic lines ectopically overexpressing either barley FC1 or FC2 were selected and evaluated under well-watered, drought, and oxidative stress conditions. Both HvFC1 and HvFC2 overexpressing transgenics showed delayed wilting and maintained higher photosynthetic performance relative to controls, after exposure to soil dehydration. In each case, HvFC overexpression significantly upregulated the nuclear genes associated with detoxification of reactive oxygen species (ROS) upon drought stress. Overexpression of HvFCs, also suppressed photo-oxidative damage induced by the deregulated tetrapyrrole biosynthesis mutant tigrinad12. Previous studies suggest that only FC1 is implicated in stress defense responses, however, our study demonstrated that both FC1 and FC2 a ect drought stress tolerance. As FC-derived free heme was proposed as a chloroplast-to-nuclear signal, heme could act as an important signal, stimulating drought responsive nuclear gene expression. This study also highlighted tetrapyrrole biosynthetic enzymes as potential targets for engineering improved crop performance, both in well-watered and water-limited environments.Dilrukshi S. K. Nagahatenna, Boris Parent, Everard J. Edwards, Peter Langridge and Ryan Whitfor
Pairing Computation on Edwards Curves with High-Degree Twists
No full textElliptic curve can be seen as the intersection of two quadratic surfaces in space. In this paper, we used the geometry approach to explain the group law for general elliptic curves given by intersection of two quadratic surfaces, then we construct the Miller function over the intersection of quadratic surfaces. As an example, we obtain the Miller function of Tate pairing computation on twisted Edwards curves. Then we present the explicit formulae for pairing computation on Edwards curves. Our formulae for the doubling step are a littler faster than that proposed by Arene et al.. Moreover, when j = 1728 and j = 0 we consider quartic and sextic twists to improve the efficiency respectively. Finally, we present the formulae of refinements technique on Edwards curves to obtain gain up when the embedding degree is odd.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000345588100012&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Computer Science, Theory & MethodsEICPCI-S(ISTP)
Abscisic acid down-regulates hydraulic conductance of grapevine leaves in isohydric genotypes only
No full textPublished September 12, 2017.Plants evolved different strategies to cope with water stress. While isohydric species maintain their midday leaf water potential (ΨM) under soil water deficit by closing their stomata, anisohydric species maintain higher stomatal aperture and exhibit substantial reductions in ΨM. It was hypothesized that isohydry is related to a locally higher sensitivity of stomata to the drought-hormone abscisic acid (ABA). Interestingly, recent lines of evidence in Arabidopsis suggested that stomatal responsiveness is also controlled by an ABA action on leaf water supply upstream from stomata. Here, we tested the possibility in grapevine that different genotypes ranging from near isohydric to more anisohydric may have different sensitivities in these ABA responses. Measurements on whole plants in drought conditions were combined with assays on detached leaves fed with ABA. Two different methods consistently showed that leaf hydraulic conductance (Kleaf) was downregulated by exogenous ABA, with strong variations depending on the genotype. Importantly, variation between isohydry and anisohydry correlated with Kleaf sensitivity to ABA, with Kleaf in the most anisohydric genotypes being unresponsive to the hormone. We propose that observed response of Kleaf to ABA may be part of the overall ABA regulation of leaf water status.Aude Coupel-Ledru, Stephen D. Tyerman, Diane Masclef, Eric Lebon, Angélique Christophe, Everard J. Edwards, and Thierry Simonnea
TEMPO2: a new pulsar timing package - III. Gravitational wave simulation
No full textG. Hobbs, F. Jenet, K. J. Lee, J. P. W. Verbiest, D. Yardley, R. Manchester, A. Lommen, W. Coles, R. Edwards and C. Shettigar
Functional differences in transport properties of natural HKT1;1 variants influence shoot Na(+) exclusion in grapevine rootstocks
No full textUnder salinity, Vitis spp. rootstocks can mediate salt (NaCl) exclusion from grafted V. vinifera scions enabling higher grapevine yields and production of superior wines with lower salt content. Until now, the genetic and mechanistic elements controlling sodium (Na(+) ) exclusion in grapevine were unknown. Using a cross between two Vitis interspecific hybrid rootstocks, we mapped a dominant quantitative trait locus (QTL) associated with leaf Na(+) exclusion (NaE) under salinity stress. The NaE locus encodes six high-affinity potassium transporters (HKT). Transcript profiling and functional characterization in heterologous systems identified VisHKT1;1 as the best candidate gene for controlling leaf Na(+) exclusion. We characterized four proteins encoded by unique VisHKT1;1 alleles from the parents, and revealed that the dominant HKT variants exhibit greater Na(+) conductance with less rectification than the recessive variants. Mutagenesis of VisHKT1;1 and TaHKT1.5-D from bread wheat, demonstrated that charged amino acid residues in the eighth predicted transmembrane domain of HKT proteins reduces inward Na(+) conductance, and causes inward rectification of Na(+) transport. The origin of the recessive VisHKT1;1 alleles was traced to V. champinii and V. rupestris. We propose that the genetic and functional data presented here will assist with breeding Na(+) -tolerant grapevine rootstocks.Sam W. Henderson, Jake D. Dunlevy, Yue Wu, Deidre H. Blackmore, Rob R. Walker, Everard J. Edwards, Matthew Gilliham, Amanda R. Walke
Edwin Edwards: A study in ethos
No full textIn November 1971, Edwin Edwards entered the final stages of his bid for the Louisiana governorship. Leading a long list of contenders in the fall democratic primaries and emerging as party victor in the December elections, Edwards seems the most promising candidate for the highest state office. The "Cajun Congressman" possesses an extraordinarily high level of ethos with men and women of widely varying ages and occupational categories. The sixteen-year veteran of politics has never lost an election; if he dominates in the February contest, he will be the first south Louisianian in thirty years to inhabit the governor"s mansion. Edwin Edwards claims that the major vehicle that he has used in building his image has been the good-will speech. His role as U. S. Congress man gave him the opportunity to use this medium to reach his bayou state constituency. Almost two years ago when Edwards embarked on an active, albeit unannounced, gubernatorial campaign, the author began this study in an attempt to answer the question- "What factors explain the ethical appeal of Edwin Edwards, Louisiana congressman, in his good-will speechmaking, 1968-1970?", Discovering the answer to this question involved taking three major steps- (1) Part one of the thesis describes the general nature of the good-will speaking of the Congressman, evaluates Edwards in the role of the good-will speaker, and examines a seven-month schedule of Edwards" occasional speechmaking. A knowledge of the specific environment within which Edwards acted out his role and built his ethos is preliminary to an under standing of the specific factors within that environment that account for his success. (2) Part two consists of a detailed description of several specific instances demonstrate the nature of audience responses to the Congressman; general press and interview commentaries concerning Edwards" appeal as a speaker; and a content analysis of interviews with individual members, illustrating opinions of Edwards as a speaker. This section is an attempt to prove that Edwards does indeed enjoy an unusually high level of ethos. (3) Part three is a critical search for the bases of Edwards" ethical appeal, involving examination of biographical data on Edwards; comments by press personnel and political associates; statements by members of the audiences at several of the speaking occasions; self-analysis of the speaker; a study of one speech in the context of the total environment in which Edwards delivered it; and texts of good-will speeches delivered in the past.Communication, Jack J. Valenti School o
Experimental investigation into the propagation of partial discharge pulses in transformers
No full textAn experimental investigation into the propagation behaviour of partial discharge (PD) pulses in a continuous disc type 6.6kV transformer winding is described in this paper. PD pulses were injected into the winding using a calibrator and the resulting current signals at the line and neutral end terminals measured using wide band current transformers. The location of the troughs (or zeros) in the frequency spectra of the measured signals change in accordance with the position of the injected pulse. The crests (or poles) in the spectra convey information about the resonance frequencies of the winding and are not affected by the position of the injected pulse. The measured spectra are compared with the spectra generated by a simulation model and although differences exist the overall shape and location of the poles and zeros are similar
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