Modelling health state preference data using a non-parametric Bayesian method

This paper reports on the findings from the application of a recently reported approach to modelling health state valuation data. The approach applies a nonparametric model to estimate the revised version of the Health Utilities Index Mark 2 (HUI 2) health state valuation algorithm using Bayesian methods. The data set is the UK HUI 2 valuation study where a sample of 51 states defined by the HUI 2 was valued by a sample of the UK general population using standard gamble. The paper presents the results from applying the nonparametric model and compares these to the original model estimated using a conventional parametric random effects model. The two models are compared in terms of their predictive performance. The paper discusses the implications of these results for future applications of the HUI 2 and further work in this field

Non-verbal communication in meetings of psychiatrists and patients with schizophrenia

Objective Recent evidence found that patients with schizophrenia display non‐verbal behaviour designed to avoid social engagement during the opening moments of their meetings with psychiatrists. This study aimed to replicate, and build on, this finding, assessing the non‐verbal behaviour of patients and psychiatrists during meetings, exploring changes over time and its association with patients' symptoms and the quality of the therapeutic relationship. Method 40‐videotaped routine out‐patient consultations, involving patients with schizophrenia, were analysed. Non‐verbal behaviour of patients and psychiatrists was assessed during three fixed, 2‐min intervals using a modified Ethological Coding System for Interviews. Symptoms, satisfaction with communication and the quality of the therapeutic relationship were also measured. Results Over time, patients' non‐verbal behaviour remained stable, whilst psychiatrists' flight behaviour decreased. Patients formed two groups based on their non‐verbal profiles, one group (n = 25) displaying pro‐social behaviour, inviting interaction and a second (n = 15) displaying flight behaviour, avoiding interaction. Psychiatrists interacting with pro‐social patients displayed more pro‐social behaviours (P < 0.001). Patients' pro‐social profile was associated reduced symptom severity (P < 0.05), greater satisfaction with communication (P < 0.001) and positive therapeutic relationships (P < 0.05). Conclusion Patients' non‐verbal behaviour during routine psychiatric consultations remains unchanged, and is linked to both their psychiatrist's non‐verbal behaviour and the quality of the therapeutic relationship

NICMOS Images of the GG Tau Circumbinary Disk

We present deep, near-infrared images of the circumbinary disk surrounding the pre-main-sequence binary star, GG Tau A, obtained with NICMOS aboard the Hubble Space Telescope. The spatially resolved proto-planetary disk scatters roughly 1.5% of the stellar flux, with a near-to-far side flux ratio of ~1.4, independent of wavelength, and colors that are comparable to the central source; all of these properties are significantly different from the earlier ground-based observations. New Monte Carlo scattering simulations of the disk emphasize that the general properties of the disk, such as disk flux, near side to far side flux ratio and integrated colors, can be approximately reproduced using ISM-like dust grains, without the presence of either circumstellar disks or large dust grains, as had previously been suggested. A single parameter phase function is fitted to the observed azimuthal variation in disk flux, providing a lower limit on the median grain size of 0.23 micron. Our analysis, in comparison to previous simulations, shows that the major limitation to the study of grain growth in T Tauri disk systems through scattered light lies in the uncertain ISM dust grain properties. Finally, we use the 9 year baseline of astrometric measurements of the binary to solve the complete orbit, assuming that the binary is coplanar with the circumbinary ring. We find that the estimated 1 sigma range on disk inner edge to semi-major axis ratio, 3.2 < Rin/a < 6.7, is larger than that estimated by previous SPH simulations of binary-disk interactions.Comment: 40 pages, 8 postscript figures, accepted for publication in Ap

Cholesterol and coronary heart disease: screening and treatment

Coronary heart disease (CHD) is a major cause of morbidity and mortality in the United Kingdom, accounting for just under one quarter of all deaths in 1995: 27% among men and 21% among women.1 Although many CHD deaths occur among elderly people, CHD accounts for 31% of male and 13% of female deaths within the 45–64 age group

Enhanced neural response to anticipation, effort and consummation of reward and aversion during Bupropion treatment

Background We have previously shown that the selective serotonergic re-uptake inhibitor, citalopram, reduces the neural response to reward and aversion in healthy volunteers. We suggest that this inhibitory effect might underlie the emotional blunting reported by patients on these medications. Bupropion is a dopaminergic and noradrenergic re-uptake inhibitor and has been suggested to have more therapeutic effects on reward-related deficits. However, how bupropion affects the neural responses to reward and aversion is unclear. Methods 17 healthy volunteers (9 female, 8 male) received 7 days of bupropion (150 mg/day) and 7 days of placebo treatment, in a double-blind crossover design. Our functional Magnetic Resonance Imaging task consisted of 3 phases; an anticipatory phase (pleasant or unpleasant cue), an effort phase (button presses to achieve a pleasant taste or to avoid an unpleasant taste) and a consummatory phase (pleasant or unpleasant tastes). Volunteers also rated wanting, pleasantness and intensity of the tastes. Results Relative to placebo, bupropion increased activity during the anticipation phase in the ventral medial prefrontal cortex (vmPFC) and caudate. During the effort phase, bupropion increased activity in the vmPFC, striatum, dorsal anterior cingulate cortex and primary motor cortex. Bupropion also increased medial orbitofrontal cortex, amygdala and ventral striatum activity during the consummatory phase. Conclusions Our results are the first to show that bupropion can increase neural responses during the anticipation, effort and consummation of rewarding and aversive stimuli. This supports the notion that bupropion might be beneficial for depressed patients with reward-related deficits and blunted affect

Right ventricular responses to CPAP therapy in obstructive sleep apnoea: CMR analysis of the MOSAIC randomised trial

Effects of continuous positive airway pressure (CPAP) on right ventricular (RV) function in patients with untreated mild-to-moderate obstructive sleep apnea (OSA) are unclear. In this exploratory analysis of cardiac magnetic resonance (CMR)-derived indices of RV function in patients with minimally symptomatic OSA from the MOSAIC randomized control trial we found no effect of CPAP on RV CMR parameters. In those with lower RV ejection fraction and higher RV end-diastolic volume (EDV) at baseline, CPAP treatment appeared to improve RV function with a significant reduction in both RV EDV and RV end-systolic volume although between-group effects were not observed. These data suggest potential merit in a larger randomized study of CPAP in patients with mild-to-moderate OSA and a greater breadth of RV dysfunction

The circumstellar environment of T Tau S at high spatial and spectral resolution

We have obtained the first high spatial (0.05'') and spectral (R~35000) resolution 2 micron spectrum of the T Tau S tight binary system using adaptive optics on the Keck II telescope. We have also obtained the first 3.8 and 4.7 micron images that resolve the three components of the T Tau multiple system, as well as new 1.6 and 2.2 micron images. Together with its very red near-infrared colors, the spectrum of T Tau Sb shows that this T Tauri star is extincted by a roughly constant extinction of Av~15 mag, which is probably the 0.7''x0.5'' circumbinary structure recently observed in absorption in the ultraviolet. T Tau Sa, which is also observed through this screen and is actively accreting, further possesses a small edge-on disk that is evidenced by warm (390 K), narrow overtone CO rovibrational absorption features in our spectrum. We find that T Tau Sa is most likely an intermediate-mass star surrounded by a semi-transparent 2-3 AU-radius disk whose asymmetries and short Keplerian rotation explain the large photometric variability of the source on relatively short timescales. We also show that molecular hydrogen emission exclusively arises from the gas that surrounds T Tau S and that its spatial and kinematic structure, while providing suggestive evidence for a jet-like structure, is highly complex.Comment: accepted for publication in the Astrophysical Journal; 41 pages, 10 figure