48 research outputs found
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'Landlocked'
The nautical imagery within my work derives directly from my involvement with the Canadian Navy, from exposure to coastal communities and my constantly transitory lifestyle.
The images which form my woodcuts are simply bold and stark. They contain a presence that is large, cold and denies the use of colour, much like the diagrams found in everday exposure within our society, as well as academic and military institutional textbooks. These woodcuts were created with the potential of having a multiple edtion of prints made of them. The reality of these woodcuts is that they will most likely never be printed. The decision in not printing them c_reates a perverse idea of waste; of time, energy and never knowing of the second existence that they may have obtained as coloured prints. The beauty of these woodcuts is apparent within the finished product. The experience of chiseling, carving and routoring the image out of the wood forms a parallel to the idea of map making and navigation.
The exposure to the Great Lakes of Canada and to some of the oceans and seas of the world created a strong bond between myself and the sea. This bond eventually led me to join the Canadian Navy. My experiences, and the close friends that I made while I was with the navy, strengthened my desire to be around the sea as much as I could. It also made me realize how painfully lonely and misplaced one could be at sea, how minute and insignificant I was on such a large body of open water. In those situations, thoughts of having been adopted and not knowing the identity of my birth parents, of moving from city to city and always being at sea created an uneasiness in me. This 'uneasiness' could be described as a void, that at times felt cold and empty, much like some of the derelict ships I've seen on beaches and along wharfs. These ships lie lifeless and still, only at times reminding society of a time and era gone by. Thus creating a nostalgic atmosphere.
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A Preliminary Discussion of the Kinematics of BHB and RR Lyrae Stars near the North Galactic Pole
The radial velocity dispersion of 67 RR Lyrae variable and blue horizontal
branch (BHB) stars that are more than 4 kpc above the galactic plane at the
North Galactic Pole is 110 km/sec and shows no trend with Z (the height above
the galactic plane). Nine stars with Z < 4 kpc show a smaller velocity
dispersion (40 +/-9 km/sec) as is to be expected if they mostly belong to a
population with a flatter distribution. Both RR Lyrae stars and BHB stars show
evidence of stream motion; the most significant is in fields RR2 and RR3 where
24 stars in the range 4.0 < Z < 11.0 kpc have a mean radial velocity of -59 +/-
16 km/sec. Three halo stars in field RR 2 appear to be part of a moving group
with a common radial velocity of -90 km/sec. The streaming phenomenon therefore
occurs over a range of spatial scales. The BHB and RR Lyrae stars in our sample
both have a similar range of metallicity (-1.2 < [Fe/H] < -2.2). Proper motions
of BHB stars in fields SA 57 (NGP) and the Anticenter field (RR 7) (both of
which lie close to the meridional plane of the Galaxy) show that the stars that
have Z 4 kpc have a Galactic V motion that is
< -200 km/sec and which is characteristic of the halo. Thus the stars that have
a flatter distribution are really halo stars and not members of the metal-weak
thick-disk.Comment: Accepted for publication in the March 1996 AJ. 15 pages, AASTeX V4.0
latex format (including figures), 2 eps figures, 2 separate AASTeX V4.0 latex
table
Evolved Eclipsing Binaries and the Age of the Open Cluster NGC 752
We present analyses of improved photometric and spectroscopic observations
for two detached eclipsing binaries at the turnoff of the open cluster NGC 752:
the 1.01 day binary DS And and the 15.53 d BD 37 410. For DS And, we find
, ,
, and . We either confirm or newly identify unusual characteristics of both
stars in the binary: the primary star is found to be slightly hotter than the
main sequence turn off and there is a more substantial discrepancy in its
luminosity compared to models (model luminosities are too large by about 40%),
while the secondary star is oversized and cooler compared to other main
sequence stars in the same cluster. The evidence points to non-standard
evolution for both stars, but most plausible paths cannot explain the low
luminosity of the primary star.
BD 37 410 only has one eclipse per cycle, but extensive spectroscopic
observations and the TESS light curve constrain the stellar masses well: and . The radius of the
main sequence primary star near definitively requires large
convective core overshooting ( pressure scale heights) in models for its
mass, and multiple lines of evidence point toward an age of
Gyr (statistical and systematic uncertainties). Because
NGC 752 is currently undergoing the transition from non-degenerate to
degenerate He ignition of its red clump stars, BD 37 410 A directly
constrains the star mass where this transition occurs.Comment: 34 pages, 23 figures, accepted for Astronomical Journa
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Evolved Eclipsing Binaries and the Age of the Open Cluster NGC 752
We present analyses of improved photometric and spectroscopic observations for two detached eclipsing binaries at the turnoff of the open cluster NGC 752: the 1.01 days binary DS And and the 15.53 days BD +37 410. For DS And, we find M1 = 1.692 ± 0.004 ± 0.010M⊙, R1 = 2.185 ± 0.004 ± 0.008R⊙, M2 = 1.184 ± 0.001 ± 0.003M⊙, and R2 = 1.200 ± 0.003 ± 0.005R⊙. We either confirm or newly identify unusual characteristics of both stars in the binary: the primary star is found to be slightly hotter than the main-sequence turnoff and there is a more substantial discrepancy in its luminosity compared to models (model luminosities are too large by about 40%), while the secondary star is oversized and cooler compared to other main-sequence stars in the same cluster. The evidence points to nonstandard evolution for both stars, but most plausible paths cannot explain the low luminosity of the primary star. BD +37 410 only has one eclipse per cycle, but extensive spectroscopic observations and the Transiting Exoplanet Survey Satellite light curve constrain the stellar masses well: M1 = 1.717 ± 0.011M⊙ and M2 = 1.175 ± 0.005M⊙. The radius of the main-sequence primary star near 2.9R⊙ definitively requires large convective core overshooting (>0.2 pressure scale heights) in models for its mass, and multiple lines of evidence point toward an age of 1.61 ± 0.03 ± 0.05 Gyr (statistical and systematic uncertainties). Because NGC 752 is currently undergoing the transition from nondegenerate to degenerate He ignition of its red clump stars, BD +37 410 A directly constrains the star mass where this transition occurs
Defence Responses of Arabidopsis thaliana to Infection by Pseudomonas syringae Are Regulated by the Circadian Clock
The circadian clock allows plants to anticipate predictable daily changes in abiotic stimuli, such as light; however, whether the clock similarly allows plants to anticipate interactions with other organisms is unknown. Here we show that Arabidopsis thaliana (Arabidopsis) has circadian clock-mediated variation in resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), with plants being least susceptible to infection in the subjective morning. We suggest that the increased resistance to Pst DC3000 observed in the morning in Col-0 plants results from clock-mediated modulation of pathogen associated molecular pattern (PAMP)-triggered immunity. Analysis of publicly available microarray data revealed that a large number of Arabidopsis defence-related genes showed both diurnal- and circadian-regulation, including genes involved in the perception of the PAMP flagellin which exhibit a peak in expression in the morning. Accordingly, we observed that PAMP-triggered callose deposition was significantly higher in wild-type plants inoculated with Pst DC3000 hrpA in the subjective morning than in the evening, while no such temporal difference was evident in arrhythmic plants. Our results suggest that PAMP-triggered immune responses are modulated by the circadian clock and that temporal regulation allows plants to anticipate and respond more effectively to pathogen challenges in the daytime
Clinical characteristics associated with the prescribing of SSRI medication in adolescents with major unipolar depression.
Unipolar major depressions (MD) emerge markedly during adolescence. National Institute for Health and Care Excellence (NICE) UK recommends psychological therapies, with accompanying selective serotonin reuptake inhibitors (SSRIs) prescribed in severe cases only. Here, we seek to determine the extent and rationale of SSRI prescribing in adolescent MD before entering a randomised clinical trial. SSRI prescribing, together with their clinical characteristics was determined in 465 adolescent patients with MD prior to receiving a standardised psychological therapy as part of the Improving mood with psychoanalytic and cognitive therapies (IMPACT) clinical trial. Overall, 88 (19Â %) had been prescribed antidepressants prior to psychological treatment. The clinical correlates varied by gender: respectively, depression severity in boys and self-harming behaviours in girls. Prescribing also differed between clinical research centres. Medical practitioners consider severity of depression in boys as an indicator for antidepressant prescribing. Self-injury in girls appears to be utilised as a prescribing aid which is inconsistent with past and current revised UK NICE guidelines.RCT Study supported by a grant to IMG (Chief Investigator) from the NIHR-HTA (trial number ISRCTN83033550, grant number 06/05/01).This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by Springer
Old English macian, Its Origin and Dissemination
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66612/2/10.1177_007542428601900105.pd
Expression of the Arabidopsis thaliana BBX32 Gene in Soybean Increases Grain Yield
Crop yield is a highly complex quantitative trait. Historically, successful breeding for improved grain yield has led to crop plants with improved source capacity, altered plant architecture, and increased resistance to abiotic and biotic stresses. To date, transgenic approaches towards improving crop grain yield have primarily focused on protecting plants from herbicide, insects, or disease. In contrast, we have focused on identifying genes that, when expressed in soybean, improve the intrinsic ability of the plant to yield more. Through the large scale screening of candidate genes in transgenic soybean, we identified an Arabidopsis thaliana B-box domain gene (AtBBX32) that significantly increases soybean grain yield year after year in multiple transgenic events in multi-location field trials. In order to understand the underlying physiological changes that are associated with increased yield in transgenic soybean, we examined phenotypic differences in two AtBBX32-expressing lines and found increases in plant height and node, flower, pod, and seed number. We propose that these phenotypic changes are likely the result of changes in the timing of reproductive development in transgenic soybean that lead to the increased duration of the pod and seed development period. Consistent with the role of BBX32 in A. thaliana in regulating light signaling, we show that the constitutive expression of AtBBX32 in soybean alters the abundance of a subset of gene transcripts in the early morning hours. In particular, AtBBX32 alters transcript levels of the soybean clock genes GmTOC1 and LHY-CCA1-like2 (GmLCL2). We propose that through the expression of AtBBX32 and modulation of the abundance of circadian clock genes during the transition from dark to light, the timing of critical phases of reproductive development are altered. These findings demonstrate a specific role for AtBBX32 in modulating soybean development, and demonstrate the validity of expressing single genes in crops to deliver increased agricultural productivity
Uncertainty and variability in models of the cardiac action potential: Can we build trustworthy models?
Cardiac electrophysiology models have been developed for over 50 years, and now include detailed descriptions of individual ion currents and sub-cellular calcium handling. It is commonly accepted that there are many uncertainties in these systems, with quantities such as ion channel kinetics or expression levels being difficult to measure or variable between samples. Until recently, the original approach of describing model parameters using single values has been retained, and consequently the majority of mathematical models in use today provide point predictions, with no associated uncertainty.
In recent years, statistical techniques have been developed and applied in many scientific areas to capture uncertainties in the quantities that determine model behaviour, and to provide a distribution of predictions which accounts for this uncertainty. In this paper we discuss this concept, which is termed uncertainty quantification, and consider how it might be applied to cardiac electrophysiology models.
We present two case studies in which probability distributions, instead of individual numbers, are inferred from data to describe quantities such as maximal current densities. Then we show how these probabilistic representations of model parameters enable probabilities to be placed on predicted behaviours. We demonstrate how changes in these probability distributions across data sets offer insight into which currents cause beat-to-beat variability in canine APs. We conclude with a discussion of the challenges that this approach entails, and how it provides opportunities to improve our understanding of electrophysiology
ENIGMA-anxiety working group : Rationale for and organization of large-scale neuroimaging studies of anxiety disorders
Altres ajuts: Anxiety Disorders Research Network European College of Neuropsychopharmacology; Claude Leon Postdoctoral Fellowship; Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, 44541416-TRR58); EU7th Frame Work Marie Curie Actions International Staff Exchange Scheme grant 'European and South African Research Network in Anxiety Disorders' (EUSARNAD); Geestkracht programme of the Netherlands Organization for Health Research and Development (ZonMw, 10-000-1002); Intramural Research Training Award (IRTA) program within the National Institute of Mental Health under the Intramural Research Program (NIMH-IRP, MH002781); National Institute of Mental Health under the Intramural Research Program (NIMH-IRP, ZIA-MH-002782); SA Medical Research Council; U.S. National Institutes of Health grants (P01 AG026572, P01 AG055367, P41 EB015922, R01 AG060610, R56 AG058854, RF1 AG051710, U54 EB020403).Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders