A Bayesian analysis for censored Rayleigh model using a generalised hypergeometric prior

Based on a type II censored sample, Bayesian estimation for the scale parameter of the Rayleigh model is carried out under the assumption of the squared error loss function. A generalised hypergeometric distribution with its versatile shape of tails is introduced as a prior, and beta special cases are examined. A simulation study is carried out to investigate the sensitivity of four special cases of this beta prior family in terms of bias, frequentist coverage and mean square error and to determine their effect on robustness. Prediction bounds are derived for the lifetime of unused components using this beta prior family. A data set is used to illustrate and support some of the findings

Logistics-related customer complaints in the South African retail industry

Abstract: Intense competition in the South African fast-moving customer goods (FMCG) retailing industry often results in price wars that encourage customer switching behaviour. Time and place utility provided by distribution, equates to customer service and forms part of the competitive strategy of retailers. Solving last-mile logistical problems in-store could be a valuable strategy in differentiation and building customer loyalty. The purpose of this study was to explore the nature of logistics-related customer complaints concerning South African mass grocery retailers (MGR) as lodged on customer complaints website Hellopeter.com, pertaining to the three largest MGR groups for the period of one year ending August 2016..

Implicit threat vigilance among violent offenders diagnosed with antisocial personality disorder:The impact of ostracism and control threat

The present study investigated the role of control as a moderator in reaction to ostracism among male violent offenders diagnosed with ASPD (N = 33) compared to a control sample consisting of males from the normal population without a known history of violence, or diagnosis of ASPD, matched for age and educational level (N = 35). Participants played an altered version of the Cyberball game in which they could control the course of the game or not. The authors predicted and found that having control prior to ostracism would mitigate the effect of ostracism on implicit threat vigilance among violent offenders diagnosed with ASPD, but not among normal individuals. The results suggest that control needs are crucial in the typology of ASPD

Radiation pressure-tunable photoluminescence and upconversion lasing on a chip

The ability to tune the wavelength of light emission on a silicon chip is important for scalable photonic networks, distributed photonic sensor networks and next generation computer architectures. Here we demonstrate light emission in a chip-scale optomechanical device, with wide tunablity provided by radiation pressure. To achieve this, we develop an optically active double-disk optomechanical system through implantation of erbium ions. We observe radiation pressure tuning of photoluminescence in the telecommunications band with a wavelength range of 520 pm, green upconversion lasing with a threshold of $340\pm 70 \; \mu$W, and optomechanical self-pulsing caused by the interplay of radiation pressure and thermal effects. These results provide a path towards widely-tunable micron-scale lasers for photonic networks.Comment: Main text 6 pages, 5 figures; Appendix 3 pages, 3 figure

Cochleatina: an enigmatic Ediacaran–Cambrian survivor among small carbonaceous fossils (SCFs)

Conspicuously few body-fossil taxa are known to span the Ediacaran-Cambrian boundary, a pattern usually taken to signal either a terminal Proterozoic mass extinction, or taphonomic failure. We draw attention to the emerging record of small carbonaceous fossils (SCFs), which exhibit continuous preservation spanning this critical interval. Here we focus on the enigmatic SCF Cochleatina, a morphologically complex coil-shaped problematicum that ranges across the Ediacaran-Cambrian divide, and potentially among the oldest fossil occurrences of metazoans. We report new material of Cochleatina canilovica from the Ediacaran of Estonia and Ukraine, which offers new characters for assessing its palaeobiology. Significantly, new specimens include sets of three-alike triplets of Cochleatina adhering to organic sheets, suggesting a clustering habit, or grouping of elements within an individual during life; an important step in constraining the morphology and ecology of this Ediacaran-Cambrian problematicum. We present revised systematic descriptions for Cochleatina and C. canilovica, and critically evaluate previous biological interpretations, drawing comparisons with metazoan, algal and protistan analogues. We reject hypotheses supporting Cochleatina as a metazoan mouthpart, and suggest new grounds for viewing Cochleatina as a potential multicomponent predator that trapped protists among microbial mats. Most occurrences are from Baltica, but we synthesise sporadic reports of Cochleatina from other palaeocontinents, pointing to its global distribution during the latest ~10 Myr of the Ediacaran and majority of the earliest Cambrian Fortunian Stage. As a rare example of an ‘Ediacaran survivor’, Cochleatina highlights the broader significance of SCFs as a novel means of tracking evolutionary patterns through the Proterozoic-Phanerozoic transition

Attitude shifts and knowledge gains: Evaluating men who have sex with men sensitisation training for healthcare workers in the Western Cape, South Africa

Background: Men who have sex with men (MSM) in South Africa experience discrimination from healthcare workers (HCWs), impeding health service access.Objectives: To evaluate the outcomes of an MSM sensitisation training programme for HCWs implemented in the Western Cape province (South Africa).Methods: A training programme was developed to equip HCWs with the knowledge, awareness and skills required to provide non-discriminatory, non-judgemental and appropriate services to MSM. Overall, 592 HCWs were trained between February 2010 and May 2012. Trainees completed self-administered pre- and post-training questionnaires assessing changes in knowledge. Two-sample t-tests for proportion were used to assess changes in specific answers and the Wilcoxon rank-sum test for overall knowledge scores. Qualitative data came from anonymous post-training evaluation forms completed by all trainees, in combination with four focus group discussions (n = 28) conducted six months after their training.Results: Fourteen per cent of trainees had received previous training to counsel clients around penile–anal intercourse, and 16% had previously received training around sexual health issues affecting MSM. There was a statistically significant improvement in overall knowledge scores (80% – 87%, p < 0.0001), specifically around penile–anal intercourse, substance use and depression after the training. Reductions in negative attitudes towards MSM and increased ability for HCWs to provide non-discriminatory care were reported as a result of the training.Conclusion: MSM sensitisation training for HCWs is an effective intervention to increase awareness on issues pertaining to MSM and how to engage around them, reduce discriminatory attitudes and enable the provision of non-judgemental and appropriate services by HCWs

Антибіотикопрофілактика в хірургії

Наук. кер.: М.Г. КононенкоГнійно-запальні післяопераційні ускладнення за останні десятиріччя набувають все більшої актуальності. Це вже стає проблемою. Такі ускладнення необхідно попереджувати. Для забезпечення тканин операційного поля антибіотиком у ефективній (бактерицидній) концентрації на весь період хірургічного втручання проводять антибіотикопрофілактику (АБП). Вона є складовою частиною комплексної профілактики гнійно-запальних ускладнень. При цитуванні документа, використовуйте посилання http://essuir.sumdu.edu.ua/handle/123456789/2734