Triplanar Model for the Gap and Penetration Depth in YBCO

YBaCuO_7 is a trilayer material with a unit cell consisting of a CuO_2 bilayer with a CuO plane of chains in between. Starting with a model of isolated planes coupled through a transverse matrix element, we consider the possibility of intra as well as interplane pairing within a nearly antiferromagnetic Fermi liquid model. Solutions of a set of three coupled BCS equations for the gap exhibit orthorhombic symmetry with s- as well as d-wave contributions. The temperature dependence and a-b in plane anisotropy of the resulting penetration depth is discussed and compared with experiment.Comment: To appear in Physical Review B1 01Mar97; 12 pages with 10 figures; RevTeX+eps

Applying economic evaluation to public health interventions: The case of interventions to promote physical activity

Copyright @ 2012 The Authors. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/2.5/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.BACKGROUND: This paper explores the application of alternative approaches to economic evaluation of public health interventions, using a worked example of exercise referral schemes (ERSs). METHODS: Cost-utility (CUA) and cost-consequence analyses (CCA) were used to assess the cost-effectiveness of ERSs. For the CUA, evidence was synthesized using a decision analytic model that adopts a lifetime horizon and NHS/Personal Social Services perspective. Outcomes were expressed as incremental cost per quality-adjusted life-year (QALY). CCA was conducted from a partial-societal perspective, including health and non-healthcare costs and benefits. Outcomes were reported in natural units, such as cases of strokes or CHD avoided. RESULTS: Compared with usual care, the incremental cost per QALY of ERS is £20 876. Based on a cohort of 100 000 individuals, CCA estimates cost of ERS at £22 million to the healthcare provider and £12 million to participants. The benefits of ERS include additional 3900 people becoming physically active, 51 cases of CHD avoided, 16 cases of stroke avoided, 86 cases of diabetes avoided and a gain of ∼800 QALYs. CONCLUSIONS: CCA might provide greater transparency than CUA in reporting the outcomes of public health interventions and have greater resonance with stakeholders involved in commissioning these interventions.This work was supported by the NIHR Health Technology Assessment programme (project number 08/72/01). This article is made available through the Brunel Open Access Publishing Fund

Effects of Capping on the (Ga,Mn)As Magnetic Depth Profile

Annealing can increase the Curie temperature and net magnetization in uncapped (Ga,Mn)As films, effects that are suppressed when the films are capped with GaAs. Previous polarized neutron reflectometry (PNR) studies of uncapped (Ga,Mn)As revealed a pronounced magnetization gradient that was reduced after annealing. We have extended this study to (Ga,Mn)As capped with GaAs. We observe no increase in Curie temperature or net magnetization upon annealing. Furthermore, PNR measurements indicate that annealing produces minimal differences in the depth-dependent magnetization, as both as-grown and annealed films feature a significant magnetization gradient. These results suggest that the GaAs cap inhibits redistribution of interstitial Mn impurities during annealing.Comment: 12 pages, 3 figures, submitted to Applied Physics Letter

Labour efficiency on-farm

End of project reportImprovements in milking efficiency have a greater influence than any other aspect of the dairy farmers work on overall farm labour inputs (Whipp, 1992). In order to facilitate the examination of milking process labour inputs, the milking process may be divided into the following three components: herding pre and post milking (transfer of cows to and from the milking parlour); milking (milking tasks / work routines within the parlour); and washing (washing of milking machine and yard). Meanwhile, within milking specifically, the number of cows milked per operator per hour is the best measure of both the performance of the operator and the milking installation (Clough, 1978). This is affected by the following three factors: the milking times of the cows, the number and arrangement of the milking units, and the operator’s work routine (Whipp, 1992). The addition of extra milking units will only increase milking performance if the operator has idle time during milking (Hansen, 1999)

Hysterectomy, endometrial destruction, and levonorgestrel releasing intrauterine system (Mirena) for heavy menstrual bleeding : systematic review and meta-analysis of data from individual patients

Peer reviewedPublisher PD

Experimental evaluation of a membrane distillation system for integration with concentrated photovoltaic/thermal (CPV/T) energy

AbstractResults are presented for a concentrated solar photovoltaic and thermal powered membrane distillation (MD) system for seawater desalination. Solar intensity data was input into a mathematical model for the solar energy system and out let temperature from the energy system was calculated. The MD module was tested for a fluctuating inlet temperature, as would be produced from a solar energy source. A maximum distillate flux of 3.4 l/m2h was recorded, though this did not correspond to the highest inlet temperature. An observed delay in the modules response to the fluctuations in temperature was due to the thermal mass of the MD unit. The conductivity of the distillate was measured to assess the effects of transient operation on the quality of the distillate produced. It was determined that although the quantity and quality of the distillate varied with the fluctuations in power supplied to the module, the effects were not significant enough to rule out the integration of the MD module with solar energy

Mixing of superconducting dx2−y2d_{x^2-y^2} state with s-wave states for different filling and temperature

We study the order parameter for mixed-symmetry states involving a major $d_{x^2-y^2}$ state and various minor s-wave states ($s$, $s_{xy}$, and $s_{x^2+y^2}$) for different filling and temperature for mixing angles 0 and $\pi/2$. We employ a two-dimensional tight-binding model incorporating second-neighbor hopping for tetragonal and orthorhombic lattice. There is mixing for the symmetric $s$ state both on tetragonal and orthorhombic lattice. The $s_{xy}$ state mixes with the $d_{x^2-y^2}$ state only on orthorhombic lattice. The $s_{x^2+y^2}$ state never mixes with the $d_{x^2-y^2}$ state. The temperature dependence of the order parameters is also studied.Comment: 10 pages, 9 figures, accepted in Physica

Predicting posttraumatic stress disorder after childbirth

Objective: around 50% of women report symptoms that indicate some aspect of their childbirth experience was 'traumatic', and at least 3.1% meet diagnosis for PTSD six months post partum. Here we aimed to conduct a prospective longitudinal study and examine predictors of birth-related trauma - predictors that included a range of pre-event factors - as a first step in the creation of a screening questionnaire. Method: of the 933 women who completed an assessment in their third trimester, 866 were followed-up at four to six week post partum. Two canonical discriminant function analyses were conducted to ascertain factors associated with experiencing birth as traumatic and, of the women who found the birth traumatic, which factors were associated with those who developed PTSD. Findings: a mix of 16 pre-birth predictor variables and event-specific predictor variables distinguished women who reported symptoms consistent with trauma from those who did not. Fourteen predictor variables distinguished women who went on to develop PTSD from those who did not. Conclusions: anxiety sensitivity to possible birthing problems, breached birthing expectations, and severity of any actual birth problem, predicted those who found the birth traumatic. Prior trauma was the single most important predictive factor of PTSD. Evaluating the utility of brief, cost-effective, and accurate screening for women at risk of developing birth-related PTSD is suggested

How much dystrophin is enough: the physiological consequences of different levels of dystrophin in the mdx mouse

Splice modulation therapy has shown great clinical promise in Duchenne muscular dystrophy, resulting in the production of dystrophin protein. Despite this, the relationship between restoring dystrophin to established dystrophic muscle and its ability to induce clinically relevant changes in muscle function is poorly understood. In order to robustly evaluate functional improvement, we used in situ protocols in the mdx mouse to measure muscle strength and resistance to eccentric contraction-induced damage. Here, we modelled the treatment of muscle with pre-existing dystrophic pathology using antisense oligonucleotides conjugated to a cell-penetrating peptide. We reveal that 15% homogeneous dystrophin expression is sufficient to protect against eccentric contraction-induced injury. In addition, we demonstrate a >40% increase in specific isometric force following repeated administrations. Strikingly, we show that changes in muscle strength are proportional to dystrophin expression levels. These data define the dystrophin restoration levels required to slow down or prevent disease progression and improve overall muscle function once a dystrophic environment has been established in the mdx mouse model