Force-insensitive optical cavity

We describe a rigidly-mounted optical cavity which is insensitive to inertial forces acting in any direction and to the compressive force used to constrain it. The design is based on a cubic geometry with four supports placed symmetrically about the optical axis in a tetrahedral configuration. To measure the inertial force sensitivity, a laser is locked to the cavity while it is inverted about three orthogonal axes. The maximum acceleration sensitivity is 2.5\times10^-11/g (where g=9.81 ms^-2), the lowest passive sensitivity to be reported for an optical cavity.Comment: 3 pages, 3 figures, journa

Development of convection along the SPCZ within a Madden-Julian oscillation

A subtropical Rossby wave propagation mechanism is proposed to account for the poleward and eastward progression of intraseasonal convective anomalies along the South Pacific Convergence Zone (SPCZ) that is observed in a significant proportion of Madden-Julian Oscillations (MJOs). Large scale convection, associated with an MJO, is assumed to be already established over the Indonesian region. The latent heating associated with this convection forces an equatorial Rossby wave response with an upper tropospheric anticyclone, centred over or slightly to the west of the convection. Large potential vorticity (PV) gradients, associated with the subtropical jet and the tropopause, lie just poleward of the anticyclone and large magnitude PV air is advected equatorwards on the eastern side of the anticyclone. This ``high'' PV air, or upper tropospheric trough, is far enough off the equator that it has associated strong horizontal temperature gradients, and it induces deep ascent on its eastern side, at a latitude of about 15-30\degr. If this deep ascent is over a region susceptible to deep convection, such as the SPCZ region, then convection may be forced or triggered. Hence convection develops along the SPCZ as a forced response to convection over Indonesia. The response mechanism is essentially one of subtropical Rossby wave propagation. This hypothesis is based on a case study of a particularly strong MJO in early 1988, and is tested by idealised modelling studies. The mechanism may also be relevant to the existence of the mean SPCZ, as a forced response to mean Indonesian convection

School-university partnerships: a model for knowledge co-creation for inclusive education. Research Brief

This report is an account of the development of one model of school-university partnership working, that has yet to be externally evaluated, that began at UCL Centre for Inclusive Education in 2013, and the subsequent contribution this has made to investigating and developing knowledge, in particular developing an increased understanding of aspects of inclusive pedagogy for both practice and research. This account presents an overview of the structure of these partnerships, describes the four main principles upon which the school-university partnerships are based with illustrative vignettes and offers a commentary by the authors, more broadly, of the benefits and challenges to be overcome to support stronger and more sustained school-university partnerships

The minimum clinically important difference on the sleep disorders inventory for people dementia

Objectives: Sleep disturbances in dementia causes distress to people with dementia and their family carers and are associated with care home admission. The Sleep Disorders Inventory (SDI) is a validated questionnaire of sleep disturbances in dementia often used to measure treatment effectiveness, but the minimum clinically important difference (MCID) is unknown. Methods: We triangulated three investigative methods to determine the MCID of the SDI. Using data on SDI from a randomised controlled trial (RCT) with 62 participants in an intervention for sleep disorders in dementia, we (1) calculated distribution-based values where MCID = 0.33 of a SD (SD) (2) an anchor based approach using quality of life (measured using DEMQOL-Proxy) as an anchor. We also employed a Delphi consensus process asking 12 clinicians, sleep researchers and family carers to rate which changes on vignettes were equivalent to a MCID. Results: We found that 0.33 SD in the SDI = 4.86. Reduction in SDI total score was not significantly correlated with improvement in DEMQOL-Proxy (Pearson's correlation = −0.01; P = 0.96) score. The Delphi consensus required two rounds to reach a consensus and concluded that changes equivalent to three points on the SDI equated to the MCID. Conclusions: Taking into account both the distribution-based values and the Delphi process we used a whole number at the midpoint and judged the minimum clinically important difference MCID to be equal to four points. We note the clinicians and carers opinions from the Delphi process determined the MCID to be lower at three points

The longitudinal variation of equatorial waves due to propagation on a varying zonal flow

The general 1-D theory of waves propagating on a zonally varying flow is developed from basic wave theory, and equations are derived for the variation of wavenumber and energy along ray paths. Different categories of behaviour are found, depending on the sign of the group velocity (cg) and a wave property, B. For B positive the wave energy and the wave number vary in the same sense, with maxima in relative easterlies or westerlies, depending on the sign of cg. Also the wave accumulation of Webster and Chang (1988) occurs where cg goes to zero. However for B negative they behave in opposite senses and wave accumulation does not occur. The zonal propagation of the gravest equatorial waves is analysed in detail using the theory. For non-dispersive Kelvin waves, B reduces to 2, and analytic solution is possible. B is positive for all the waves considered, except for the westward moving mixed Rossby-gravity (WMRG) wave which can have negative as well as positive B. Comparison is made between the observed climatologies of the individual equatorial waves and the result of pure propagation on the climatological upper tropospheric flow. The Kelvin wave distribution is in remarkable agreement, considering the approximations made. Some aspects of the WMRG and Rossby wave distributions are also in qualitative agreement. However the observed maxima in these waves in the winter westerlies in the eastern Pacific and Atlantic are not consistent with the theory. This is consistent with the importance of the sources of equatorial waves in these westerly duct regions due to higher latitude wave activity

Neurophysiology and Neural Computation

Contains reports on three research projects

Physiology

Contains reports on three research projects

How do care home staff use non-pharmacological strategies to manage sleep disturbances in residents with dementia: The SIESTA qualitative study

Background: Sleep disturbances affect 38% of care home residents living with dementia. They are often treated with medication, but non-pharmacological interventions may be safer and effective yet more difficult to implement. In the SIESTA study (Sleep problems In dEmentia: interviews with care home STAff) we explored care home staffs’ experience of managing sleep disturbances in their residents living with dementia. Methods: We conducted one-to-one semi-structured interviews in four UK care homes, and purposively recruited a maximum variation sample of 18 nurses and care assistants, who were each interviewed once. We used a topic guide and audio-recorded the interviews. Two researchers independently analysed themes from transcribed interviews. Results: Staff used a range of techniques that often worked in improving or preventing residents’ sleep disturbance. During the daytime, staff encouraged residents to eat well, and be physically active and stimulated to limit daytime sleep. In the evening, staff settled residents into dark, quiet, comfortable bedrooms often after a snack. When residents woke at night, they gave them caffeinated tea or food, considered possible pain and discomfort, and reassured residents they were safe. If residents remained unsettled, staff would engage them in activities. They used telecare to monitor night-time risk. Staff found minimising daytime napping difficult, described insufficient staffing at night to attend to reorient and guide awake residents and said residents frequently did not know it was night-time. Conclusions: Some common techniques, such as caffeinated drinks, may be counterproductive. Future non-pharmacological interventions should consider practical difficulties staff face in managing sleep disturbances, including struggling to limit daytime napping, identifying residents’ night-time needs, day-night disorientation, and insufficient night-time staffing