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Search Results: 1 - 10 of 411114 matches for " S O'Dea "
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Evaluation of Nutrition and Physical Activity Knowledge, Attitudes, Self Efficacy and Behaviors in Teachers and Children after Implementation of the “Healthy Active Kids” Online Program in Australian Elementary Schools  [PDF]
Jennifer A. ODea
Health (Health) , 2016, DOI: 10.4236/health.2016.84031
Abstract: The aims were to examine change in nutrition and physical activity knowledge, self efficacy and attitudes in a cohort of 23 teachers and 304 year 5 and 6 children after the “Healthy Active Kids” online program and to assess any behavioral change in children’s self reported nutrition and physical activity behaviors and investigate the predictors of nutrition knowledge gain in teachers and children. Results found significant (p < 0.0001) increases in teacher and student knowledge of the five food groups; key nutrients provided by each food group, The Australian Guide to Healthy Eating; food labelling laws, identification of common names for fats, sugars and salts on food labels, food proportions on the Healthy Food Plate and the level and percentage of water in the human body and human brain. Teacher attitudes towards the importance of nutrition and diet and self efficacy related to teaching nutrition in class improved (p < 0.01). The final regression model for predictors of the dependent variable, knowledge gain in students was R = 0.53, Adjusted R square = 0.28 (F = 4.76, p < 0.01) indicating that 28% of the variation in knowledge gain was predicted by the negative (low) Time 1 knowledge. Changes to eating habits reported by children were “drinking more water each day” (89.1%) and “eating foods from the five food groups each day” (76.2%); “sharing information about food labels with your family” (52.4%); “reading food labels when you go shopping” (50.0%); “changing what is on your dinner plate each night” (44.2%); “vegetables that you eat now that you didn’t eat before” (42.1%) and “fruits that you eat now” (39%). Results suggest that the development of basic nutrition knowledge is still very important for both teachers and students, but that other factors such as self efficacy, empowerment and skill development also contribute to nutrition behavior change in children.
Late gadolinium enhancement and subclinical cardiac dysfunction on cardiac MRI in asymptomatic HIV-positive men
A Loy,R Morgan,S O'Dea,E Takacs
Journal of the International AIDS Society , 2012, DOI: 10.7448/ias.15.6.18150
Abstract: Background: HIV is associated with an increased risk of cardiovascular disease (CVD) and related clinical events. While traditional risk factors play an important role in the pathology of cardiovascular disease, HIV infection and its sequelae of immune activation and inflammation may have significant effects on the myocardium before becoming clinically evident. Cardiac MRI (CMR) can be used to detect the pattern of these subclinical changes. This will lead to a better understanding of risk factors contributing to cardiovascular disease prior to it becoming clinically significant in HIV-positive patients. Methods: Prospective cohort study of 127 asymptomatic HIV-positive men on ART compared to 35 matched controls. Baseline demographics, HIV parameters, 12-lead ECG, routine biochemistry, and traditional cardiovascular risk factors were recorded. Images were acquired on a 3T Achieva Philips MRI scanner with 5 channel phase array cardiac coil and weight-based IV gadolinium was given at 0.15 mmol/kg dose with post-contrast inversion recovery imaging after 10 minutes. Results: 6/127 (4.7%) of asymptomatic HIV-positive men had late gadolinium enhancement (LGE) on MRI verses 1/35 (2.9%) in the control group. In 3/6 (50%) of cases this was in a classical infarction pattern with subendocardial involvement. 3/6 (50%) were consistent with prior myocarditis. There was no significant difference in mean LVEF (66.93% vs 65.18%), LVMI (60.05g/m2 vs 55.94g/m2) or posterolateral wall thickness (8.28 mm and 8.16 mm) between cases and controls respectively. There was significantly more diastolic dysfunction, E:A ratio < 1, found in the HIV-positive group, 18% vs 7% of controls (p = 0.037). Framingham risk did not predict either of these outcomes. Conclusions: There is an increased incidence of LGE detected on CMR in this asymptomatic HIV-positive cohort. Two distinct pathological processes were identifed as causing these changes, myocardial infarction and myocarditis. These findings were independent of traditional cardiac risk factors, duration of HIV infection and ART therapy. Sub clinical cardiac dysfunction may be underreported in other cardiac evaluation studies. The true impact of other potential risk factors may also be underestimated, highlighting the need for the development of more complex prediction models.
Management of dyslipidaemia in an HIV-positive cohort
A Loy,L Townsend,S O'Dea,F Mulcahy
Journal of the International AIDS Society , 2012, DOI: 10.7448/ias.15.6.18128
Abstract: Background: Dyslipidaemia, secondary to both HIV and the use of antiretroviral therapy (ART) is well recognised, with HIV replication and immune status also thought to contribute to the risk. Traditionally the HIV physician has looked after HIV with primary care physicians (GP) managing non-HIV-related medical issues. However with the ageing population and the effectiveness of ART the HIV physician is diversifying to focus management strategies on preventative measures also. Method: 127 subjects were recruited. All subjects were HIV-positive males without any traditional cardiovascular disease symptoms or history. Details of patients demographics, family history, statin therapy, and primary care physician contact were collected. Baseline parameters were recorded and fasting bloods taken. Results: 127 asymptomatic HIV-positive males were recruited. 74/127 (58.3%) met the EACS criteria for statin prescription. 33/74 (44.6%) were on a statin. There was no significant difference between the class of antiretroviral prescribed, (NNRTI v PI) and lipid abnormalities (p=0.628). Hypertension and increased waist:hip ratio significantly increased the chances of the patient being hyperlipidaemic. Patients were more likely to be prescribed a statin if they were older, had hypertension, an increased waist circumference, increased Framingham risk, increased brain natriuretic peptide (BNP), or were diagnosed HIV-positive for longer (p<0.05). Pravastatin (21/33 [63.6%]), was most commonly prescribed statin. 24.2% received their statin prescription from their HIV physician, with 75.8% receiving their prescription from their GP. 5/21 (23.8%) on pravastatin met the target verses 7/7 (100%) on atorvastatin verses 2/2 (100%) on simvastatin versus 1/3 (33.3%) on rosuvastatin (p=0.02). Meeting lipid targets was less successful in the protease inhibitor group (1/9) 11.1% versus 11/21 (52.4%) in the NNRTI group (p=0.16). Conclusion: The majority met criteria for lipid management but less than half of those were prescribed it. Of those, most received treatment from their GP. Nearly half of those on statins did not meet lipid targets. HIV physicians were most likely to prescribe pravastatin and those on pravastatin were the least likely to achieve lipid targets when compared to the other statins. HIV physicians need to diversify their knowledge base and have clearly defined management strategies for the management of dyslipidaemia.
Rotation-Measures across Parsec-scale Jets of FRI radio galaxies
P. Kharb,D. C. Gabuzda,C. P. O'Dea,P. Shastri,S. A. Baum
Physics , 2009, DOI: 10.1088/0004-637X/694/2/1485
Abstract: We present the results of a parsec-scale polarization study of three FRI radio galaxies - 3C66B, 3C78 and 3C264 - obtained with the Very Long Baseline Array at 5, 8 and 15 GHz. Parsec-scale polarization has been detected in a large number of beamed radio-loud active galactic nuclei, but in only a handful of the relatively unbeamed radio galaxies. We report here the detection of parsec-scale polarization at one or more frequencies in all three FRI galaxies studied. We detect Faraday rotation measures of the order of a few hundred rad/m^2 in the nuclear jet regions of 3C78 and 3C264. In 3C66B polarization was detected at 8 GHz only. A transverse rotation measure gradient is observed across the jet of 3C78. The inner-jet magnetic field, corrected for Faraday rotation, is found to be aligned along the jet in both 3C78 and 3C264, although the field becomes orthogonal further from the core in 3C78. The RM values in 3C78 and 3C264 are similar to those previously observed in nearby radio galaxies. The transverse RM gradient in 3C78, the increase in the degree of polarization at the jet edge, the large rotation in the polarization angles due to Faraday rotation and the low depolarization between frequencies, suggests that a layer surrounding the jet with a sufficient number of thermal electrons and threaded by a toroidal or helical magnetic field is a good candidate for the Faraday rotating medium. This suggestion is tentatively supported by Hubble Space Telescope optical polarimetry but needs to be examined in a greater number of sources.
HST observations of nearby radio-loud early-type galaxies
G. A. Verdoes Kleijn,S. A. Baum,P. T. de Zeeuw,C. P. O'Dea
Physics , 1999, DOI: 10.1086/301135
Abstract: We present and analyse HST/WFPC2 broad- and narrow-band observations of the central regions of 19 nearby radio-loud early-type galaxies. Together with two more galaxies they form a complete sample of Fanaroff & Riley Type I galaxies. We obtained V- and I-band images and narrow-band images centered on the \HalphaNII emission lines. We use archival data for six galaxies. We describe the data reduction, give isophotal fits and analyse the central emission-line gas and dust distributions. Our main conclusions are the following. Although obscuration by dust inhibits a direct determination of central cusp slopes, the data suggest most but not all galaxies have shallow cores. Dust is detected in all but two galaxies. There is a wide variety of central dust morphologies, ranging from central disks to lanes and irregular distributions. The analysis suggests the difference between disks and lanes is intrinsic and not due to different viewing angles. Central emission-line gas is detected in all galaxies. Extended low-surface-brightness emission is always associated with the dust features. In a subsequent paper we will present a detailed analysis of the relation between these central properties and the nuclear activity.
A complete sample of GHz-Peaked-Spectrum radio sources and its radio properties
C. Stanghellini,C. P. O'Dea,D. Dallacasa,S. A. Baum,R. Fanti,C. Fanti
Physics , 1998, DOI: 10.1051/aas:1998270
Abstract: We define a complete sample of thirty-three GHz-Peaked-Spectrum (GPS) radio sources based on their spectral properties. We present measurements of the radio spectra and polarization of the complete sample and a list of additional GPS sources which fail one or more criteria to be included in the complete sample. The majority of the data have been obtained from quasi-simultaneous multi-frequency observations at the Very Large Array (VLA) during 3 observing sessions. Low frequency data from the Westerbork Synthesis Radio Telescope (WSRT) and from the literature have been combined with the VLA data in order to better define the spectral shape. The objects presented here show a rather wide range of spectral indices at high and low frequencies, including a few cases where the spectral index below the turnover is close to the theoretical value of 2.5 typical of self-absorbed incoherent synchrotron emission. Faint and diffuse extended emission is found in about 10% of the sources. In the majority of the GPS sources, the fractional polarization is found to be very low, consistent with the residual instrumental polarization of 0.3%.
VLBA observations of GHz-Peaked-Spectrum radio sources at 15 GHz
C. Stanghellini,D. Dallacasa,C. P. O'Dea,S. A. Baum,R. Fanti,C. Fanti
Physics , 2001, DOI: 10.1051/0004-6361:20011101
Abstract: We present VLBA observations at 15 GHz of ten GHz Peaked Spectrum (GPS) radio sources. The cores are often difficult or impossible to locate. When likely cores are found, they account for a small fraction of the flux density in GPS galaxies - around or below 2%, while in GPS quasars they can account for more than 20% of the total flux density. We detect low polarization in the GPS sources -- i.e., typically less than a few percent and often less than one percent. This establishes that low polarization in the parsec scale structure is an important defining characteristic of the GPS sources. The dichotomy in the radio morphology versus optical identification, i.e., galaxies are symmetric and quasars are not, is basically confirmed from these new data, which also indicate that the radio emission from GPS quasars is dominated by a jet, with often a weak or hidden core, suggesting they are at moderate angles to the line of sight, and so are only moderately beamed.
Neutral Hydrogen (21 cm) Absorption in Seyfert Galaxies: Evidence for Free-free Absorption and Sub-kiloparsec Gaseous Disks
J. F. Gallimore,S. A. Baum,C. P. O'Dea,A. Pedlar,E. Brinks
Physics , 1999, DOI: 10.1086/307853
Abstract: Active galaxies are thought to be both fueled and obscured by neutral gas removed from the host galaxy and funneled into a central accretion disk. We performed a VLA imaging survey of 21 cm absorption in Seyfert and starburst nuclei to study the neutral gas in the near-nuclear environment. With the exception of NGC 4151, the absorbing gas traces 100 pc scale, rotating disks aligned with the outer galaxy disk. These disks appear to be rich in atomic gas relative to nuclear disks in non-active spirals. We find no strong evidence for rapid in-fall or out-flow of neutral hydrogen, but our limits on the mass infall rates are compatible with that required to feed a Seyfert nucleus. Among the galaxies surveyed here, neutral hydrogen absorption traces parsec-scale gas only in NGC 4151. Based on the kinematics of the absorption line, the disk symmetry axis appears to align with the radio jet axis rather than the outer galaxy axis. The most surprising result is that we detect no 21 cm absorption towards the central radio sources of the hidden Seyfert 1 nuclei Mrk 3, Mrk 348, and NGC 1068. Moreover, 21 cm absorption is commonly observed towards extended radio jet structure but appears to avoid central, compact radio sources in Seyfert nuclei. To explain these results, we propose that 21 cm absorption towards the nucleus is suppressed by either free-free absorption, excitation effects (i.e., enhanced spin temperature), or rapid motion in the obscuring gas. Ironically, the implications of these effects is that the obscuring disks must be small, typically not larger than a few tens of parsecs.
A Multiwavelength Study of Three Hybrid Blazars
E. C. Stanley,P. Kharb,M. L. Lister,H. L. Marshall,C. O'Dea,S. Baum
Physics , 2015,
Abstract: We present multiwavelength imaging observations of PKS 1045-188, 8C 1849+670, and PKS 2216-038, three radio-loud active galactic nuclei from the MOJAVE-Chandra Sample that straddle the Fanaroff-Riley (FR) boundary between low- and high-power jets. These hybrid sources provide an excellent opportunity to study jet emission mechanisms and the influence of the external environment. We used archival VLA observations, and new Hubble and Chandra observations to identify and study the spectral properties of five knots in PKS 1045-188, two knots in 8C 1849+670, and three knots in PKS 2216-038. For the seven X-ray visible knots, we constructed and fit the broadband spectra using synchrotron and inverse Compton/cosmic microwave background (IC/CMB) emission models. In all cases, we found that the lack of detected optical emission ruled out the X-ray emission from the same electron population that produces radio emission. All three sources have high total extended radio power, similar to that of FR II sources. We find this is in good agreement with previously studied hybrid sources, where high-power hybrid sources emit X-rays via IC/CMB and the low-power hybrid sources emit X-rays via synchrotron emission. This supports the idea that it is total radio power rather than FR morphology that determines the X-ray emission mechanism. We found no significant asymmetries in the diffuse X-ray emission surrounding the host galaxies. Sources PKS 1045-188 and 8C 1849+670 show significant differences in their radio and X-ray termination points, which may result from the deceleration of highly relativistic bulk motion.
Supersymmetric Harmonic Maps into Lie Groups
F. O'Dea
Physics , 2001,
Abstract: We look at the supersymmetric generalization of harmonic maps into Lie groups, known to physicists as the chiral model. Explicit solutions to the equations are found and examined using Backlund transformations.
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