Control of silica polymerisation during ferromanganese slag sulphuric acid digestion and water leaching

A major obstacle to the hydrometallurgical treatment of ferromanganese slags is the way in which silica polymerisation is controlled during sulphuric acid digestion and water leaching. In an acidic medium, silica enters in solution and forms silicic acid, which polymerises into silica gel and makes solid-liquid separation difficult. This article will show that the quick leach model, also called the water-starved system, limits silica solubilisation and its subsequent polymerisation during manganese extraction from ferromanganese slags by rejecting most of the ferromanganese slag silica content in the leach residue. It will further illustrate that the silica content in the residue is dependent on the acid concentration used during acid digestion. It will also show that dissolved silica in the pregnant leach solution is high when an unrestricted quantity of water is used and low when the water quantity is restricted during water leaching. Furthermore, a method for silica gel recovery from ferromanganese slag will be presented, as well as the silica gel analysis, in order to confirm the theory presented in this article. Manganese extraction of up to 90% is obtained and the leach residue presents good latent hydraulic properties, which can be used as an addition to Portland cement or a gypsum replacement. More than 95% of the initial silica content of the slag is rejected in the leach residue, and a residue silica content of more than 27% is obtained. Thus, silica solubilisation and polymerisation is controlled and solid-liquid separation accelerated.The BMBF (Federal Ministry of Education and Research, Germany) (DLR FKZ: 01DG12057) and the National Research Foundation (NRF), South Africa (UID 75971-2011).http://www.elsevier.com/locate/hydromet2017-12-31hb2017Materials Science and Metallurgical Engineerin

International consensus on the most useful physical examination tests used by physiotherapists for patients with headache: A Delphi study

Background: A wide range of physical tests have been published for use in the assessment of musculoskeletal dysfunction in patients with headache. Which tests are used depends on a physiotherapist's clinical and scientific background as there is little guidance on the most clinically useful tests. Objectives: To identify which physical examination tests international experts in physiotherapy consider the most clinically useful for the assessment of patients with headache. Design/methods: Delphi survey with pre-specified procedures based on a systematic search of the literature for physical examination tests proposed for the assessment of musculoskeletal dysfunction in patients with headache. Results: Seventeen experts completed all three rounds of the survey. Fifteen tests were included in round one with eleven additional tests suggested by the experts. Finally eleven physical examination tests were considered clinically useful: manual joint palpation, the cranio-cervical flexion test, the cervical flexion-rotation test, active range of cervical movement, head forward position, trigger point palpation, muscle tests of the shoulder girdle, passive physiological intervertebral movements, reproduction and resolution of headache symptoms, screening of the thoracic spine, and combined movement tests. Conclusions: Eleven tests are suggested as a minimum standard for the physical examination of musculoskeletal dysfunctions in patients with headache

“It feels like someone is hammering my feet”: Understanding pain and its management from the perspective of people with Multiple Sclerosis

Background: Pain affects around 63% of people with multiple sclerosis (pwMS). Biomedical treatments demonstrate limited efficacy. More research is needed to understand pain from the individual’s perspective in order to better inform a patient-centred approach that improves engagement, self-management and outcome. Objective: The objective of this paper is to explore pwMS’ experience and responses to pain, and their perspectives on pain management. Methods: Twenty-five in-depth, semi-structured telephone interviews were conducted. Interviews were audiotaped, transcribed and analysed using an inductive thematic analysis approach with elements of grounded theory. Results: Key themes included vivid descriptions of pain and beliefs that pain is unpredictable, a sign of damage and may worsen. Anger was a common emotional response. Two dominant pain management themes emerged: one related to pain reduction and another to acceptance. Those focusing on pain reduction appeared to engage in cycles in which they struggled with symptoms and experienced continued distress. Conclusion: Findings identify pain-related beliefs, emotional reactions and disparate pain-management attitudes. All may influence pwMS’ responses to pain and what they ask of their clinicians. Uncovering pwMS’ personal beliefs about pain, and introducing a broader biopsychosocial understanding of pain in the clinical context, may provide opportunities to rectify potentially unhelpful management choices and enhance pain acceptance