31 research outputs found
Maternal feeding behaviour and young children's dietary quality: A cross-sectional study of socially disadvantaged mothers of two-year old children using the Theory of Planned Behaviour
Background: Having breakfast, eating food 'cooked from scratch' and eating together as a family have health and psychosocial benefits for young children. This study investigates how these parentally determined behaviours relate to children's dietary quality and uses a psychological model, the Theory of Planned Behaviour (TPB), to investigate socio-cognitive predictors of these behaviours in socially disadvantaged mothers of young children in Scotland. Method: Three hundred mothers of children aged 2 years (from 372 invited to participate, 81% response rate), recruited via General Practitioners, took part in home-based semi-structured interviews in a cross-sectional survey of maternal psychological factors related to their children's dietary quality. Regression analyses examined statistical predictors of maternal intentions and feeding behaviours. Results: Mothers of children with poorer quality diets were less likely than others to provide breakfast every day, cook from 'scratch' and provide 'proper sit-down meals'. TPB socio-cognitive factors (intentions, perceived behavioural control) significantly predicted these three behaviours, and attitudes, norms, and perceived behavioural control significantly predicted mothers' intentions, with medium to large effect sizes. Conclusions: Interventions to improve young children's dietary health could benefit from a focus on modifying maternal motivations and attitudes in attempts to improve feeding behaviours
An X-Ray Pulsar in the Oxygen-Rich Supernova Remnant G292.0+1.8
We report the discovery of pulsed X-ray emission from the compact object CXOU
J112439.1-591620 within the supernova remnant (SNR) G292.0+1.8 using the High
Resolution Camera on the Chandra X-ray Observatory. The X-ray period
(P=0.13530915 s) is consistent with extrapolation of the radio pulse period of
PSR J1124-5916 for a spindown rate of dP/dt=7.6E-13 s/s. The X-ray pulse is
single peaked and broad with a FWHM width of 0.23P (83 degrees). The
pulse-averaged X-ray spectral properties of the pulsar are well described by a
featureless power law model with an absorbing column density, N_H= 3.1E21
atoms/cm^2; photon index, gamma = 1.6; and unabsorbed 0.3-10 keV band
luminosity, L_X = 7.2E32 erg/s. We plausibly identify the location of the
pulsar's termination shock. Pressure balance between the pulsar wind and the
larger synchrotron nebula, as well as lifetime issues for the X-ray-emitting
electrons, argues for a particle- dominated PWN that is far from the minimum
energy condition. Upper limits on the surface temperature of the neutron star
are at, or slightly below, values expected from ``standard'' cooling curves.
There is no optical counterpart to the new pulsar; its optical luminosity is at
least a factor of 5 below that of the Crab pulsar.Comment: 5 pages, including 3 postscript figs, LaTeX, submitted to ApJ Letter
The Structure of the Oxygen-rich Supernova Remnant G292.0+1.8 from Chandra X-ray Images: Shocked Ejecta and Circumstellar Medium
We present results from the observation of the young Galactic supernova
remnant (SNR) G292.0+1.8 with the Advanced CCD Imaging Spectrometer (ACIS) on
board the {\it Chandra X-ray Observatory}. In the 0.3 8 keV band, the high
resolution ACIS images reveal a complex morphology consisting of knots and
filaments, as well as the blast wave around the periphery of the SNR. We
present equivalent width (EW) maps for the elemental species O, Ne, Mg, and Si,
which allow us to identify regions of enhanced metallicity in the SNR.
G292.0+1.8 is bright in O, Ne, and Si; weaker in S and Ar; with little Fe. The
EW and broad-band images indicate that the metal-rich ejecta are distributed
primarily around the periphery of the SNR. The central belt-like structure has
normal solar-type composition, strongly suggesting that it is primarily
emission from shocked circumstellar medium rather than metal-rich ejecta. We
propose that the belt traces its origin to enhanced mass loss in the star's
equatorial plane during the slow, red supergiant phase. We also identify thin
filaments with normal composition, centered on and extending nearly
continuously around the outer boundary of the SNR. These may originate in a
shell caused by the stellar winds from the massive progenitor in the red/blue
supergiant phases, over-run by the blast wave.Comment: 5 pages, 2 color images, Accepted by ApJ Letters, The full article
with better-quality figures can be obtained at
http://www.astro.psu.edu/users/park/g292_1.ps.g
Text message intervention to reduce frequency of binge drinking among disadvantaged men: the TRAM RCT
BackgroundSocially disadvantaged men are more likely to binge drink frequently and to experience high levels of alcohol-related harm.ObjectivesTo test the effectiveness and cost-effectiveness of a text message intervention in reducing the frequency of binge drinking among disadvantaged men.Study designA four-centre, parallel-group, pragmatic, individually randomised controlled trial was conducted. Randomisation was carried out using a secure remote web-based system. It was stratified by participating centre and recruitment method and restricted using block sizes of randomly varying lengths.SettingThe study was conducted in the community. Members of the public helped to develop the study methods.ParticipantsParticipants were men aged 25–44 years who had ≥ 2 episodes of binge drinking (> 8 units of alcohol in a single session) in the preceding 28 days. Men were recruited from areas of high deprivation.InterventionsAn empirically and theoretically based text message intervention was delivered by 112 interactive text messages over a 12-week period. The control group received an attentional control comprising 89 text messages on general health.Primary outcome measureThe primary outcome measure was the proportion of men consuming > 8 units of alcohol on ≥ 3 occasions (in the previous 28 days) at 12 months post intervention.ResultsThe recruitment target of 798 was exceeded and 825 men were randomised. Retention was high and similar in the intervention (84.9%) and control (86.5%) groups. Most men in the intervention group engaged enthusiastically with the text messages: almost all (92%) replied to text messages and over two-thirds (67%) replied more than 10 times. The intervention was estimated to have had a modest, statistically non-significant effect on the primary outcome at the 12-month follow-up [odds ratio 0.79, 95% confidence interval (CI) 0.57 to 1.08]. This corresponds to a net reduction of 5.7% in regular binge drinking. Five secondary outcomes showed small non-significant and inconsistent effects on alcohol consumption, with one suggesting a positive effect and four suggesting an adverse effect. Both the short- and the long-term cost per quality-adjusted life-year (QALY) analysis suggested that the brief intervention was dominated by a ‘do-nothing’ option. The intervention’s impacts on patterns of alcohol consumption, QALYs and downstream costs were inconsistent and uncertain.LimitationsThe study used an active control that, combined with the recruitment procedures and baseline assessments, could have biased the treatment effect towards the null. The measurement of alcohol consumption relied on self-reported drinking.ConclusionsThe trial has demonstrated that it is possible to recruit and retain large numbers of socially disadvantaged men in a research study. The text messages delivered a complex theoretically and empirically based intervention that fostered enthusiastic engagement with the key components of the behaviour change sequence. The intervention produced a modest, statistically non-significant effect on the primary outcome, with wide CIs. Further research is needed to reduce uncertainty about the treatment effect. The methods developed for this study provide a platform for the design and testing of interventions to reduce inequalities in health
Modifying Alcohol Consumption to Reduce Obesity: A Randomized Controlled Feasibility Study of a Complex Community-based Intervention for Men
ObjectivesBeing obese and drinking more than 14 units of alcohol per week places men at very high risk of developing liver disease. This study assessed the feasibility of a trial to reduce alcohol consumption. It tested the recruitment strategy, engagement with the intervention, retention and study acceptability.MethodsMen aged 35–64 years who drank >21 units of alcohol per week and had a BMI > 30 were recruited by two methods: from GP patient registers and by community outreach. The intervention was delivered by a face to face session followed by a series of text messages. Trained lay people (Study Coordinators) delivered the face to face session. Participants were followed up for 5 months from baseline to measure weekly alcohol consumption and BMI.ResultsThe recruitment target of 60 was exceeded, with 69 men recruited and randomized. At baseline, almost all the participants (95%) exceeded the threshold for a 19-fold increase in the risk of dying from liver disease. The intervention was delivered with high fidelity. A very high follow-up rate was achieved (98%) and the outcomes for the full trial were measured. Process evaluation showed that participants responded as intended to key steps in the behaviour change strategy. The acceptability of the study methods was high: e.g. 80% of men would recommend the study to others.ConclusionsThis feasibility study identified a group at high risk of liver disease. It showed that a full trial could be conducted to test the effectiveness and cost-effectiveness of the intervention
A High Statistics Search for Ultra-High Energy Gamma-Ray Emission from Cygnus X-3 and Hercules X-1
We have carried out a high statistics (2 Billion events) search for
ultra-high energy gamma-ray emission from the X-ray binary sources Cygnus X-3
and Hercules X-1. Using data taken with the CASA-MIA detector over a five year
period (1990-1995), we find no evidence for steady emission from either source
at energies above 115 TeV. The derived upper limits on such emission are more
than two orders of magnitude lower than earlier claimed detections. We also
find no evidence for neutral particle or gamma-ray emission from either source
on time scales of one day and 0.5 hr. For Cygnus X-3, there is no evidence for
emission correlated with the 4.8 hr X-ray periodicity or with the occurrence of
large radio flares. Unless one postulates that these sources were very active
earlier and are now dormant, the limits presented here put into question the
earlier results, and highlight the difficulties that possible future
experiments will have in detecting gamma-ray signals at ultra-high energies.Comment: 26 LaTeX pages, 16 PostScript figures, uses psfig.sty to be published
in Physical Review
Mode of action of DNA-competitive small molecule inhibitors of tyrosyl DNA phosphodiesterase 2
TDP2 is a 5’-tyrosyl DNA phosphodiesterase important for the repair of DNA adducts generated by non-productive (abortive) activity of topoisomerase II. TDP2 facilitates therapeutic resistance to topoisomerase poisons, which are widely used in the treatment of a range of cancer types. Consequently, TDP2 is an interesting target for the development of small molecule inhibitors that could restore sensitivity to topoisomerase-directed therapies. Previous studies identified a class of deazaflavin-based molecules that showed inhibitory activity against TDP2 at therapeutically useful concentrations, but their mode of action was uncertain. We have confirmed that the deazaflavin series inhibits TDP2 enzyme activity in a fluorescence-based assay, suitable for HTS-screening. We have gone on to determine crystal structures of these compounds bound to a ‘humanised’ form of murine TDP2. The structures reveal their novel mode of action as competitive ligands for the binding site of an incoming DNA substrate, and point the way to generating novel and potent inhibitors of TDP2