Aqueous foams coarsen with time due to gas diffusion through the liquid between the bubbles. The mean bubble size grows, and small bubbles vanish. However, coarsening is little understood for foams with an intermediate liquid content, particularly in the presence of surfactant-induced attractive forces between the bubbles, measured by the interface contact angle where thin films meet the bulk liquid. Rigorous bubble growth laws have yet to be developed, and the evolution of bulk foam properties is unclear. We present a quasistatic numerical model for coarsening in two-dimensional wet foams, focusing on growth laws and related bubble properties. The deformation of bubble interfaces is modelled using a finite-element approach, and the gas flow through both films and Plateau borders is approximated. We give results for disordered two-dimensional wet foams with $256$ to $1024$ bubbles, at liquid fractions from $2\,\%$ to $25\,\%$, beyond the zero-contact-angle unjamming transition, and with contact angles up to $10^\circ$. Simple analytical models for the bubble pressures, film lengths and coarsening growth rates are developed to aid interpretation. If the contact angle is non-zero, we find that a prediction of the coarsening rate approaches a non-zero value as the liquid fraction is increased. We also find that an individual bubble's effective number of neighbours determines whether it grows or shrinks to a good approximation.

Optical tracking systems typically trade off between astrometric precision and field of view. In this work, we showcase a networked approach to optical tracking using very wide field-of-view imagers that have relatively low astrometric precision on the scheduled OSIRIS-REx slingshot manoeuvre around Earth on 22 Sep 2017. As part of a trajectory designed to get OSIRIS-REx to NEO 101955 Bennu, this flyby event was viewed from 13 remote sensors spread across Australia and New Zealand to promote triangulatable observations. Each observatory in this portable network was constructed to be as lightweight and portable as possible, with hardware based off the successful design of the Desert Fireball Network. Over a 4-h collection window, we gathered 15 439 images of the night sky in the predicted direction of the OSIRIS-REx spacecraft. Using a specially developed streak detection and orbit determination data pipeline, we detected 2 090 line-of-sight observations. Our fitted orbit was determined to be within about 10 km of orbital telemetry along the observed 109 262 km length of OSIRIS-REx trajectory, and thus demonstrating the impressive capability of a networked approach to Space Surveillance and Tracking.

Both radial and low degree and order g-mode nonradial pulsations are predicted for luminous blue variables that occur in the blue supergiant region of the Hertzsprung-Russell diagram. It is found that the radial strange modes have very large growth rates due to helium ionization in models at surface effective temperatures between 10,000 and 20,000 K.

The low amplitude radially pulsating classical Cepheid Polaris (α UMi) has well observed decreasing radial velocity and light amplitudes and an increasing period. Recent work indicates that Polaris may stop pulsating by 1995 (Dinshaw et al, 1989), which would make it an excellent indicator for the red edge of the Cepheid instability strip in the Hertzsprung-Russell diagram.

We have calculated Population I envelope models with 200 mass shells of a 5.5 M⊙ star near Teff = 5700 K and log(L/L⊙) = 3.11 which match Polaris’ characteristics (Arellano Ferro, 1984). Models were calculated using the Linear Non Adiabatic pulsation analysis code of Castor (1971). The effects of convection on the pulsational stability were calculated with the time dependent convection theory of Cox, Brownlee and Eilers (1966) as discussed by Cox and Guili (1968). The characteristics of the models were altered until the appropriate period, temperature and luminosity were obtained.

We increase the metal abundance in the envelope of Double Mode Cepheids (DMCs) in order to remove the period ratio mass discrepancy. By increasing the value of Z, we are able to increase the opacity by a factor of 2 to 2.5. We find that for a star of 5 solar masses, with a temperature of 5957 K, and a luminosity of 1050 times that of the sun, an increase in the metal abundance starting at the Log (T) value of 4.79 and reaching a maximum Z value of 0.3 in the Log (T) range of 4.8 to 5.3 produces a period ratio P1/P0 = 0.7089, and a value of P0 = 3.001 days. The value of Z returns to 0.02 at Log (T) = 5.62. The enhanced zone (part of which convects) is located well below the H and He convective regions. The enhanced region is also stable against downward mixing since the radiative gradient is so sub-adiabatic.

Two-hundred-and-seventy-nine patients (103 men, 176 women) were followed-up 1–2 years after an act of non-fatal deliberate self-harm. Of 155 patients offered a psychiatric out-patient appointment at the time, only 68 completed the treatment. A further act of deliberate self-harm was committed by 26 men and 41 women within twelve months. The factors most highly associated with repetition were previous psychiatric treatment, a previous act of deliberate self-harm, and a criminal record. These factors held good for a separate series of patients. Significantly more repeaters received prolonged psychiatric care after the initial episode of deliberate self-harm. The implications of these findings for the clinical management of such patients are discussed.

In this study 368 patients were interviewed after they had attended the Bristol Royal Infirmary Accident and Emergency Department following a non-fatal act of deliberate self-harm. There were twice as many women (247) as men (121), and two thirds of the patients were in the 15–35 age group. Ninety-five per cent had taken a drug overdose, most commonly one or more of the tranquillizers, antidepressants, hypnotics or analgesics. Seventy-eight per cent had taken drugs prescribed by a doctor. Half the patients mentioned interpersonal conflict as a major precipitating factor in the episode. A psychiatric diagnosis was completed for all admitted patients, of whom 52 per cent were considered to be suffering from neurotic depression, 29 per cent from personality disorder, 12 per cent from functional psychosis and 10 per cent from alcohol addiction. Almost half had deliberately harmed themselves on a previous occasion. The series showed a greater than average incidence of unemployment, overcrowded living conditions, divorce and antisocial behaviour. The implications of these findings for the clinical management and prevention of non-fatal deliberate self-harm are discussed.

The diet and milk from a herd of dairy cows were analysed regularly for 90Sr and calcium. The ‘observed ratio’ (the ratio of 90Sr to calcium in the milk divided by the ratio of 90Sr to calcium in the diet) was found to be 0·10 against 90Sr in favour of calcium, which corresponds well with the results of other workers. The amount of 90Sr secreted into the milk was 1·2% of the total ingested. Similar values were obtained using stable strontium data.

Soil samples from different depths and herbage were taken from three areas with different cultivation histories and analysed for 90Sr and calcium. The effect of ploughing on the vertical distribution of 90Sr in soil and on the 90Sr levels in vegetation was examined.