Thin-shell wormholes: Linearization stability

The class of spherically-symmetric thin-shell wormholes provides a particularly elegant collection of exemplars for the study of traversable Lorentzian wormholes. In the present paper we consider linearized (spherically symmetric) perturbations around some assumed static solution of the Einstein field equations. This permits us to relate stability issues to the (linearized) equation of state of the exotic matter which is located at the wormhole throat.Comment: 4 pages; ReV_TeX 3.0; one postscript figur

Accurate molecular imaging of small animals taking into account animal models, handling, anaesthesia, quality control and imaging system performance

Small-animal imaging has become an important technique for the development of new radiotracers, drugs and therapies. Many laboratories have now a combination of different small-animal imaging systems, which are being used by biologists, pharmacists, medical doctors and physicists. The aim of this paper is to give an overview of the important factors in the design of a small animal, nuclear medicine and imaging experiment. Different experts summarize one specific aspect important for a good design of a small-animal experiment

Pain medicine content, teaching and assessment in medical school curricula in Australia and New Zealand

Background: The objective of pain medicine education is to provide medical students with opportunities to develop their knowledge, skills and professional attitudes that will lead to their becoming safe, capable, and compassionate medical practitioners who are able to meet the healthcare needs of persons in pain. This study was undertaken to identify and describe the delivery of pain medicine education at medical schools in Australia and New Zealand. Method: All 23 medical schools in Australia and New Zealand in 2016 were included in this study. A structured curriculum audit tool was used to obtain information on pain medicine curricula including content, delivery, teaching and assessment methods. Results: Nineteen medical schools (83%) completed the curriculum audit. Neurophysiology, clinical assessment, analgesia use and multidimensional aspects of pain medicine were covered by most medical schools. Specific learning objectives for pain medicine were not identified by 42% of medical schools. One medical school offered a dedicated pain medicine module delivered over 1 week. Pain medicine teaching was delivered at all schools by a number of different departments throughout the curriculum. Interprofessional learning (IPL) in the context of pain medicine education was not specified by any of the medical schools. The mean time allocated for pain medicine teaching over the entire medical course was just under 20 h. The objective structured clinical examination (OSCE) was used by 32% of schools to assess knowledge and skills in pain medicine. 16% of schools were unsure of whether any assessment of pain medicine education took place. Conclusion: This descriptive study provides important baseline information for pain medicine education at medical schools in Australia and New Zealand. Medical schools do not have well-documented or comprehensive pain curricula that are delivered and assessed using pedagogically-sound approaches considering the complexity of the topic, the prevalence and public health burden of pain

Systematic review of pain medicine content, teaching, and assessment in medical school curricula internationally

Introduction: Pain management is a major health care challenge in terms of the significant prevalence of pain and the negative consequences of poor management. Consequently, there have been international calls to improve pain medicine education for medical students. This systematic review examines the literature on pain medicine education at medical schools internationally, with a particular interest in studies that make reference to: a defined pain medicine curriculum, specific pain medicine learning objectives, dedicated pain education modules, core pain topics, medical specialties that teach pain medicine, elective study opportunities, hours allocated to teaching pain medicine during the curriculum, the status of pain medicine in the curriculum (compulsory or optional), as well as teaching, learning, and assessment methods. Methods: A systematic review was undertaken of relevant studies on pain medicine education for medical students published between January 1987 and May 2018 using PubMed, Medline, Excerpta Medica database (EMBASE), Education Resources Information Center (ERIC), and Google Scholar, and Best Evidence Medical Education (BEME) data bases. Results: Fourteen studies met the inclusion criteria. Evaluation of pain medicine curricula has been undertaken at 383 medical schools in Australia, New Zealand, the United States of America (USA), Canada, the United Kingdom (UK), and Europe. Pain medicine was mostly incorporated into medical courses such as anaesthesia or pharmacology, rather than presented as a dedicated pain medicine module. Ninety-six percent of medical schools in the UK and USA, and nearly 80% of medical schools in Europe had no compulsory dedicated teaching in pain medicine. On average, the median number of hours of pain content in the entire curriculum was 20 in Canada (2009), 20 in Australia and New Zealand (2018), 13 in the UK (2011), 12 in Europe (2012/2013), and 11 in the USA (2009). Neurophysiology and pharmacology pain topics were given priority by medical schools in all countries. Lectures, seminars, and case-based instruction were the teaching methods most commonly employed. When it was undertaken, medical schools mostly assessed student competency in pain medicine using written examinations rather than clinical assessments. Conclusions: This systematic review has revealed that pain medicine education at medical schools internationally does not adequately respond to societal needs in terms of the prevalence and public health impact of inadequately managed pain

Patient attitudes towards analgesia and their openness to non-pharmacological methods such as acupuncture in the emergency department

Aims: To investigate patient attitudes to analgesia, opioids and non-pharmacological analgesia including acupuncture, in the ED. Methods: ED patients with pain were surveyed regarding: pain scores, satisfaction, addiction concern, non-pharmacological methods of pain relief, and acupuncture. Data were analysed using logistic regression. Results: Of 196 adult patients, 52.8% were ‘very satisfied’ with analgesia. Most patients (84.7%) would accept non-pharmacological methods including acupuncture (68.9%) and 78.6% were not concerned about addiction. Satisfaction was associated with male gender, and ‘adequate analgesia’ but not with opioids. Conclusion: Most patients were generally satisfied with ED analgesia and were open to non-pharmacologic analgesia including acupuncture

Optimal fetal growth – a misconception?

Alterations in fetal growth trajectory, either in terms of individual organs or the fetal body, constitute part of a suite of adaptive responses that the fetus can make to a developmental challenge such as inadequate nutrition. Nonetheless, despite substantial changes in nutrition in many countries over recent centuries, mean birthweight has changed relatively little. Low birthweight is recognised as a risk factor for later noncommunicable disease, although the developmental origins of such risk are graded across the full range of fetal growth and birthweight. Many parental and environmental factors, some biological, some cultural, can influence fetal growth, and these should not be viewed as abnormal. We argue that the suggestion of establishing a universal standard for optimal fetal growth ignores the breadth of these normal fetal responses. It may influence practice adversely, through incorrect estimation of gestational age and unnecessary elective deliveries. It raises ethical as well as practical issues

The Effect of Yarding Technique on Yarding Productivity and Cost: Conventional Single-Hitch Suspension vs. Horizontal Double-Hitch Suspension

Cable yarding is a well establish technology for the extraction of timber in steep terrain. However, it is encumbered with relatively low productivity and high costs, and as such this technology needs to adapt and progress to remain viable. The development of biomass as a valuable byproduct, and the availability of processors to support yarder operations, lend themselves to increasing the level of whole-tree extraction. Double-hitch carriages have been developed to allow for full suspension of whole-tree and tree-length material. This study compared a standard single-hitch to a double-hitch carriage under controlled conditions, namely in the same location using the same yarder with downhill extraction. As expected, the double-hitch carriage took longer to load up (+14%), but was able to achieve similar productivity (10–11 m3 per productive machine hour) through increased inhaul speed (+15%). The importance of this study is that it demonstrates both the physical and economic feasibility of moving to whole-tree extraction using the double-hitch type carriage for longer corridors, for settings with limited deflection, or areas with lower tolerance for soil disturbance