1,108 research outputs found

    Aboriginal and Non-Aboriginal Students Learn About Natural Health Products from Different Information Sources

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    Natural health products (NHPs) include naturally derived botanical and nonbotanical products. Past research indicates a high prevalence of NHPs use amongst adults in the United States and Canada but does not clearly characterize NHPs use amongst students, ethnic variations of such use, or how users learn about NHPs. We hypothesize that there is a difference between Aboriginal and non-Aboriginal students in how they learn about NHPs. To investigate this question, we conducted a cross-sectional study at First Nations University of Canada and the University of Regina, Saskatchewan, Canada, during the fall of 2011. Aboriginal (n=214) and non-Aboriginal (n=749) students participated in the 28 question survey. Our results indicate that Aboriginal students who use NHPs are found in all age groups, are mostly female, are smokers and nonsmokers, and learn about NHPs from Elders and healers. Compared to nonAboriginal students, Aboriginal students rely significantly less on alternative and conventional health providers, electronic media, print media, and advertising as their sources of information about NHPs. Thus, Aboriginal students use Elders or healers as a primary source of information to learn about NHPs, as compared to non-Aboriginal students. Future work should investigate the role of Elder traditional educators to convey NHPs information directed specifically to Aboriginal university students

    Src phosphorylation converts Mdm2 from a ubiquitinating to a neddylating E3 ligase

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    Murine double minute-2 protein (Mdm2) is a multifaceted phosphorylated protein that plays a role in regulating numerous proteins including the tumor suppressor protein p53. Mdm2 binds to and is involved in conjugating either ubiquitin or Nedd8 (Neural precursor cell expressed, developmentally down-regulated 8) to p53. Although regulation of the E3 ubiquitin activity of Mdm2 has been investigated, regulation of the neddylating activity of Mdm2 remains to be defined. Here we show that activated c-Src kinase phosphorylates Y281 and Y302 of Mdm2, resulting in an increase in Mdm2 stability and its association with Ubc12, the E2 enzyme of the neddylating complex. Mdm2-dependent Nedd8 conjugation of p53 results in transcriptionally inactive p53, a process that is reversed with a small molecule inhibitor to either Src or Ubc12. Thus, our studies reveal how Mdm2 may neutralize and elevate p53 in actively proliferating cells and also provides a rationale for using therapies that target the Nedd8 pathway in wild-type p53 tumors

    On-sky tests of the CuReD and HWR fast wavefront reconstruction algorithms with CANARY

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    CuReD (Cumulative Reconstructor with domain Decomposition) and HWR (Hierarchical Wavefront Reconstructor) are novel wavefront reconstruction algorithms for the Shack–Hartmann wavefront sensor, used in the single-conjugate adaptive optics. For a high-order system they are much faster than the traditional matrix–vector-multiplication method. We have developed three methods for mapping the reconstructed phase into the deformable mirror actuator commands and have tested both reconstructors with the CANARY instrument. We find out that the CuReD reconstructor runs stably only if the feedback loop is operated as a leaky integrator, whereas HWR runs stably with the conventional integrator control. Using the CANARY telescope simulator we find that the Strehl ratio (SR) obtained with CuReD is slightly higher than that of the traditional least-squares estimator (LSE). We demonstrate that this is because the CuReD algorithm has a smoothing effect on the output wavefront. The SR of HWR is slightly lower than that of LSE. We have tested both reconstructors extensively on-sky. They perform well and CuReD achieves a similar SR as LSE. We compare the CANARY results with those from a computer simulation and find good agreement between the two

    Adaptive Optics for Astronomy

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    Adaptive Optics is a prime example of how progress in observational astronomy can be driven by technological developments. At many observatories it is now considered to be part of a standard instrumentation suite, enabling ground-based telescopes to reach the diffraction limit and thus providing spatial resolution superior to that achievable from space with current or planned satellites. In this review we consider adaptive optics from the astrophysical perspective. We show that adaptive optics has led to important advances in our understanding of a multitude of astrophysical processes, and describe how the requirements from science applications are now driving the development of the next generation of novel adaptive optics techniques.Comment: to appear in ARA&A vol 50, 201

    EAGLE multi-object AO concept study for the E-ELT

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    EAGLE is the multi-object, spatially-resolved, near-IR spectrograph instrument concept for the E-ELT, relying on a distributed Adaptive Optics, so-called Multi Object Adaptive Optics. This paper presents the results of a phase A study. Using 84x84 actuator deformable mirrors, the performed analysis demonstrates that 6 laser guide stars and up to 5 natural guide stars of magnitude R<17, picked-up in a 7.3' diameter patrol field of view, allow us to obtain an overall performance in terms of Ensquared Energy of 35% in a 75x75 mas^2 spaxel at H band, whatever the target direction in the centred 5' science field for median seeing conditions. The computed sky coverage at galactic latitudes |b|~60 is close to 90%.Comment: 6 pages, to appear in the proceedings of the AO4ELT conference, held in Paris, 22-26 June 200

    Effects of brassinosteroid, auxin, and cytokinin on ethylene production in Arabidopsis thaliana plants

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    Inflorescence stalks produced the highest amount of ethylene in response to IAA as compared with other plant parts tested. Leaf age had an effect on IAA-induced ethylene with the youngest leaves showing the greatest stimulation. The highest amount of IAA-induced ethylene was produced in the root or inflorescence tip with regions below this producing less. Inflorescence stalks treated with IAA, 2,4-D, or NAA over a range of concentrations exhibited an increase in ethylene production starting at 1 μM with increasingly greater responses up to 100 μM, followed by a plateau at 500 μM and a significant decline at 1000 μM. Both 2,4-D and NAA elicited a greater response than IAA at all concentrations tested in inflorescence stalks. Inflorescence leaves treated with IAA, 2,4-D, or NAA exhibited the same trend as inflorescence stalks. However, they produced significantly less ethylene. Inflorescence stalks and leaves treated with 100 μM IAA exhibited a dramatic increase in ethylene production 2 h following treatment initiation. Inflorescence stalks showed a further increase 4 h following treatment initiation and no further increase at 6 h. However, there was a slight decline between 6 h and 24 h. Inflorescence leaves exhibited similar rates of IAA-induced ethylene between 2 h and 24 h. Light and high temperature caused a decrease in IAA-induced ethylene in both inflorescence stalks and leaves. Three auxin-insensitive mutants were evaluated for their inflorescence's responsiveness to IAA. aux2 did not produce ethylene in response to 100 μM IAA, while axr1-3 and axr1-12 showed reduced levels of IAA-induced ethylene as compared with Columbia wild type. Inflorescences treated with brassinolide alone had no effect on ethylene production. However, when brassinolide was used in combination with IAA there was a dramatic increase in ethylene production above the induction promoted by IAA alone

    Discovery of inverse-Compton X-ray emission and estimate of the volume-averaged magnetic field in a galaxy group

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    Observed in a significant fraction of clusters and groups of galaxies, diffuse radio synchrotron emission reveals the presence of relativistic electrons and magnetic fields permeating large-scale systems of galaxies. Although these non-thermal electrons are expected to upscatter cosmic microwave background photons up to hard X-ray energies, such inverse-Compton (IC) X-ray emission has so far not been unambiguously detected on cluster/group scales. Using deep, new proprietary XMM-Newton observations (\sim200 ks of clean exposure), we report a 4.6σ\sigma detection of extended IC X-ray emission in MRC 0116+111, an extraordinary group of galaxies at z=0.131z = 0.131. Assuming a spectral slope derived from low-frequency radio data, the detection remains robust to systematic uncertainties. Together with low-frequency radio data from GMRT, this detection provides an estimate for the volume-averaged magnetic field of (1.9±0.3)(1.9 \pm 0.3) μ\muG within the central part of the group. This value can serve as an anchor for studies of magnetic fields in the largest gravitationally bound systems in the Universe.Comment: 11 pages, 7 figures, accepted for publication in MNRA

    What about if buildings respond to my mood?

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    This work analyzes the possibilities of interaction between the built environment and its users, focused on the responsiveness of the first to the emotions of the latter. Transforming the built environment according to the mood, feelings, and emotions of users, moment by moment, is discussed and analyzed. The main goal of this research is to define a responsive model by which the built environment can respond in a personalized way to the users’ emotions. For such, computational technical issues, building construction elements and users’ interaction are identified and analyzed. Case studies where occurs an interaction between the physical space and users are presented. We define a model for an architecture that is responsive to the user’s emotions assuming the individual at one end and the space at the other. The interaction between both ends takes place according to intermediate steps: the collection of data, the recognition of emotion, and the execution of the action that responds to the detected emotion. As this work focuses on an innovative and disruptive aspect of the built environment, the recognition of the new difficulties and related ethical issues are discussed.info:eu-repo/semantics/acceptedVersio
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