Quantum Monte Carlo study of a positron in an electron gas

Quantum Monte Carlo calculations of the relaxation energy, pair-correlation function, and annihilating-pair momentum density are presented for a positron immersed in a homogeneous electron gas. We find smaller relaxation energies and contact pair-correlation functions in the important low-density regime than predicted by earlier studies. Our annihilating-pair momentum densities have almost zero weight above the Fermi momentum due to the cancellation of electron-electron and electron-positron correlation effects

The effectiveness of paid services in supporting carers' employment in England

This paper explores the effectiveness of paid services in supporting unpaid carers’ employment in England. There is currently a new emphasis in England on ‘replacement care’, or paid services for the cared-for person, as a means of supporting working carers. The international evidence on the effectiveness of paid services as a means of supporting carers’ employment is inconclusive and does not relate specifically to England. The study reported here explores this issue using the 2009/10 Personal Social Services Survey of Adult Carers in England. The study finds a positive association between carers’ employment and receipt of paid services by the cared-for person, controlling for covariates. It therefore gives support to the hypothesis that services for the cared-for person are effective in supporting carers’ employment. Use of home care and a personal assistant are associated on their own with the employment of both men and women carers, while use of day care and meals-on-wheels are associated specifically with women’s employment. Use of short-term breaks are associated with carers’ employment when combined with other services. The paper supports the emphasis in English social policy on paid services as a means of supporting working carers, but questions the use of the term ‘replacement care’ and the emphasis on ‘the market’

Effects of Meditation on Heart Rate and Blood Pressure: A Mindfulness-based Study

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Urinary diversion and bladder reconstruction/replacement using intestinal segments for intractable incontinence or following cystectomy

Background Surgery performed to improve or replace the function of the diseased urinary bladder has been carried out for over a century. Main reasons for improving or replacing the function of the urinary bladder are bladder cancer, neurogenic bladder dysfunction, detrusor overactivity and chronic inflammatory diseases of the bladder (such as interstitial cystitis, tuberculosis and schistosomiasis). There is still much uncertainty about the best surgical approach. Options available at the present time include: (1) conduit diversion (the creation of various intestinal conduits to the skin) or continent diversion (which includes either a rectal reservoir or continent cutaneous diversion), (2) bladder reconstruction and (3) replacement of the bladder with various intestinal segments. Objectives To determine the best way of improving or replacing the function of the lower urinary tract using intestinal segments when the bladder has to be removed or when it has been rendered useless or dangerous by disease. Search methods We searched the Cochrane Incontinence Group Specialised Trials Register (searched 28 October 2011), which contains trials identified from the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and CINAHL, and handsearching of journals and conference proceedings, and the reference lists of relevant articles. Selection criteria All randomised or quasi-randomised controlled trials of surgery involving transposition of an intestinal segment into the urinary tract. Data collection and analysis Trials were evaluated for appropriateness for inclusion and for risk of bias by the review authors. Three review authors were involved in the data extraction. Data were combined in a meta-analysis when appropriate. Main results Five trials met the inclusion criteria with a total of 355 participants. These trials addressed only five of the 14 comparisons pre-specified in the protocol. One trial reported no statistically significant differences in the incidence of upper urinary tract infection, uretero-intestinal stenosis and renal deterioration in the comparison of continent diversion with conduit diversion. The confidence intervals were all wide, however, and did not rule out important clinical differences. In a second trial, there was no reported difference in the incidence of upper urinary tract infection and uretero-intestinal stenosis when conduit diversions were fashioned from either ileum or colon. A meta-analysis of two trials showed no statistically significant difference in daytime or nocturnal incontinence amongst participants who were randomised to ileocolonic/ileocaecal segment bladder replacement compared to an ileal bladder replacement. However, one small trial suggested that bladder replacement using an ileal segment compared to using an ileocolonic segment may be better in terms of lower rates of nocturnal incontinence. There were no differences in the incidence of dilatation of upper tract, daytime urinary incontinence or wound infection using different intestinal segments for bladder replacement. However the data were reported for 'renal units', but not in a form that allowed appropriate patient-based paired analyses. No statistically significant difference was found in the incidence of renal scarring between anti-refluxing versus freely refluxing uretero-intestinal anastomotic techniques in conduit diversions and bladder replacement groups. Again, the outcome data were not reported as paired analysis or in form to carry out paired analysis. Authors' conclusions The evidence from the included trials was very limited. Only five studies met the inclusion criteria; these were small, of moderate or poor methodological quality, and reported few of the pre-selected outcome measures. This review did not find any evidence that bladder replacement (orthotopic or continent diversion) was better than conduit diversion following cystectomy for cancer. There was no evidence to suggest that bladder reconstruction was better than conduit diversion for benign disease. The clinical significance of data from one small trial suggesting that bladder replacement using an ileal segment compared to using an ileocolonic segment is better in terms of lower rates of nocturnal incontinence is uncertain. The small amount of usable evidence for this review suggests that collaborative multi centre studies should be organised, using random allocation where possible. This review is published as a Cochrane Review in the Cochrane Database of Systematic Reviews 2012, Issue 2. Cochrane Reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and the Cochrane Database of Systematic Reviews should be consulted for the most recent version of the Review.</p

Screening Seniors for Risk of Functional Decline: Results of a Survey in Family Practice

To measure functional status, determine risk of functional decline and assess consistency between responses and standardized instruments. Design: A mailed survey which measured functional impairment, recent hospitalization and bereavement. A positive response on at least one of these factors indicated that the individual was “at risk” for functional decline. A random sample (n=73) of “at risk” subjects (specifically, family practice patients aged 70 and older) were assessed by a nurse. Results: The response rate was 89% (369/415), 59% of seniors were female and the mean age was 77.1 (SD=5.5) years. Self-reported risk, based on activities of daily living (ADLs), was associated with impairment in at least one basic ADL (p\u3c0.0005) using a standardized instrument. The positive predictive value of the survey for ADL impairment was 65%. Conclusion: Response to a mailed survey was high and self-reported ADL risks were consistent with findings from standardized assessment tools

Testing the Effectiveness of Lecture Capture Technology Using Prior GPA as a Performance Indicator

This empirical study examines whether making lecture capture technology available in a face-to-face lecture environment can improve students’ ability to learn the course material. We examine student performance in undergraduate principles courses in computer science and economics. However, rather than simply comparing average course grades between lecture capture and non-lecture capture classes, we use student grade point average (GPA) as a predictor of course grades earned in non-lecture capture classes and lecture capture classes taught by the same professors using the same course materials. Our results imply that making lecture capture technology available in face-to-face lectures does not appear to impact high GPA students’ ability to learn the course material one way or the other. However, low GPA students in one of the lecture capture courses earned significantly lower grades relative to low GPA students in the non-lecture capture class

An efficient k.p method for calculation of total energy and electronic density of states

An efficient method for calculating the electronic structure in large systems with a fully converged BZ sampling is presented. The method is based on a k.p-like approximation developed in the framework of the density functional perturbation theory. The reliability and efficiency of the method are demostrated in test calculations on Ar and Si supercells