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Contexts. - An evidence base for complementary and alternative medicine (CAM) consumption within general populations is emerging. However, research data on CAM use for headache disorders remain poorly documented. This paper, constituting the first critical review of literature on this topic, provides a synopsis and evaluation of the research findings on CAM use among patients with headache and migraine. Methods. - A comprehensive search of literature from 2000 to 2011 in CINAHL, MEDLINE, AMED, and Health Sources was conducted. The search was confined to peer-reviewed articles published in English reporting empirical research findings of CAM use among people with primary headache or migraine. Results. - The review highlights a substantial level of CAM use among people with headache and migraine. There is also evidence of many headache and migraine sufferers using CAM concurrent to their conventional medicine use. Overall, the existing studies have been methodologically weak and there is a need for further rigorous research employing mixed method designs and utilizing large national samples. Discussion. - The critical review highlights the substantial prevalence of CAM use among people with headache and migraine as a significant health care delivery issue, and health care professionals should be prepared to inquire and discuss possible CAM use with their patients during consultations. Health care providers should also pay attention to the possible adverse effects of CAM or interactions between CAM and conventional medical treatments among headache and migraine patients. © 2012 American Headache Society.

The topic is covered in 3 parts. Simulation, describes how the fragmentation of multiphase materials can be modelled. Particle population statistics and texture quantification techniques are used along with stereological theorems and integral geometry to develop mathematical models. Measurement, deals with the problems of particle composition distribution (PCD) (and therefore liberation) measurements. Existing methods of reconstruction from 1 and 2 dimension measurements, taken under the microscope, to 3 dimension particles are reviewed. A new method which uses stereology and integral geometry is also described. Practical use, shows how mineral liberation affects the operation of mineral processing plants. The book is divided into 14 chapters: Introduction; Particle population statistics - size, shape, volume, composition and their distribution; Quantification of texture - covariance function, selection of reference models and their calibration; Random uniform isotropic fragmentation of multiphase materials - PCD, liberation; Assessment of the RUIF model - comparison with the IAC model of Meloy theorems of liberation under RUIF; Comparison of the RUIF results with previous models and experimental data; Measurement of PCD - physical separation methods, grain counting, image analysis; Reconstruction methods for PCD or liberation from methods on sections - existing methods; Development and validation of a new method of particle composition - distribution determination from measurements on sections; Analysis of the breakage of multiphase materials; Liberation in physical separation processes - process efficiency and analysis; Simulation of grinding of multiphase materials; Behaviour of unliberated particles in mineral separation; and Selection of equipment for liberation in mineral processing plants - organisation of circuits for optimal liberation., The topic is covered in 3 parts. Simulation, describes how the fragmentation of multiphase materials can be modelled. Particle population statistics and texture quantification techniques are used along with stereological theorems and integral geometry to develop mathematical models. Measurement, deals with the problems of particle composition distribution (PCD) (and therefore liberation) measurements. Existing methods of reconstruction from 1 and 2 dimension measurements, taken under the microscope, to 3 dimension particles are reviewed. A new method which uses stereology and integral geometry is also described. Practical use, shows how mineral liberation affects the operation of mineral processing plants. The book is divided into 14 chapters: Introduction; Particle population statistics - size, shape, volume, composition and their distribution; Quantification of texture - covariance function, selection of reference models and their calibration; Random uniform isotropic fragmentation of multiphase materials - PCD, liberation; Assessment of the RUIF model - comparison with the IAC model of Meloy theorems of liberation under RUIF; Comparison of the RUIF results with previous models and experimental data; Measurement of PCD - physical separation methods, grain counting, image analysis; Reconstruction methods for PCD or liberation from methods on sections - existing methods; Development and validation of a new method of particle composition - distribution determination from measurements on sections; Analysis of the breakage of multiphase materials; Liberation in physical separation processes - process efficiency and analysis; Simulation of grinding of multiphase materials; Behaviour of unliberated particles in mineral separation; and Selection of equipment for liberation in mineral processing plants - organisation of circuits for optimal liberation.

The stereological methods of measuring the degree of mineral liberation after comminution are examined: one developed by the BRGM (Barbery and others) and the other by Imperial College of Science and Technology (Jones and others)., The stereological methods of measuring the degree of mineral liberation after comminution are examined: one developed by the BRGM (Barbery and others) and the other by Imperial College of Science and Technology (Jones and others).

Energy analysis and is potential applications to mineral or metallurgical proces selection and development are described. A comparison of alternatives is carried out in order to assess, in terms of energy, the various potential combinations of processes which are available to produce simultaneously all products concerned. One application is given for the recovery of values from pyrite cinders., Energy analysis and is potential applications to mineral or metallurgical proces selection and development are described. A comparison of alternatives is carried out in order to assess, in terms of energy, the various potential combinations of processes which are available to produce simultaneously all products concerned. One application is given for the recovery of values from pyrite cinders.

The paper presents an attempt to derive a model to simulate the operation of the CIP circuit at the Mine Vezina plant., The paper presents an attempt to derive a model to simulate the operation of the CIP circuit at the Mine Vezina plant.

Galena depression, after flotation with alkyl xanthates in a bulk Pb-Cu concentrate, is of importance in the processing of complex sulphide ores by the conventional method: Cu-Pb flotation together with sphalerite depression followed by Cu-Pb separation by galena depression. Chromate ion addition is commonly used to achieve this latter depression. The desorption kinetics of ethyl xanthate adsorbed on natural galena have been studied to determine the influence of chromate concentration. Reaction order and rate constants were obtained by recording the ultraviolet spectra of species during reaction, and oxidised species formed on the galena surface during reaction were identified by electron spectroscopy for chemical analysis., Galena depression, after flotation with alkyl xanthates in a bulk Pb-Cu concentrate, is of importance in the processing of complex sulphide ores by the conventional method: Cu-Pb flotation together with sphalerite depression followed by Cu-Pb separation by galena depression. Chromate ion addition is commonly used to achieve this latter depression. The desorption kinetics of ethyl xanthate adsorbed on natural galena have been studied to determine the influence of chromate concentration. Reaction order and rate constants were obtained by recording the ultraviolet spectra of species during reaction, and oxidised species formed on the galena surface during reaction were identified by electron spectroscopy for chemical analysis.

A model of liberation prediction has been developed, which can be calibrated for ore texture and breakage using image analysers. The model is demonstrated for the case of a Poisson polyhedra ore texture and monodisperse fragment size. It enables the prediction of the complete composite particle distribution, and is therefore important for integration of ore breakage models, with minerals separation models., A model of liberation prediction has been developed, which can be calibrated for ore texture and breakage using image analysers. The model is demonstrated for the case of a Poisson polyhedra ore texture and monodisperse fragment size. It enables the prediction of the complete composite particle distribution, and is therefore important for integration of ore breakage models, with minerals separation models.

Techniques which are applicable to systems of solids and aqueous solutions are dealt with. A first group of techniques is a case where water is an inconvenience and where the sample must be separated from the place where it was prepared; these techniques include infared spectroscopy and emission-types of spectroscopy (x-ray flourescence, ionics and photoelectronic emission).. A second group comprises the resonance and ultra-violet absorption as the principal types. The new methods are complementary to those already in use, such as the flotability test, the determinarion of surface charhes and of mineral mobilities, and the clear definition of surface species by infrered radiation., Techniques which are applicable to systems of solids and aqueous solutions are dealt with. A first group of techniques is a case where water is an inconvenience and where the sample must be separated from the place where it was prepared; these techniques include infared spectroscopy and emission-types of spectroscopy (x-ray flourescence, ionics and photoelectronic emission).. A second group comprises the resonance and ultra-violet absorption as the principal types. The new methods are complementary to those already in use, such as the flotability test, the determinarion of surface charhes and of mineral mobilities, and the clear definition of surface species by infrered radiation.

Batch laboratory machines should: allow simple, reliable, reproducible operations; be sufficiently instrumented that measurements of physical and chemical parameters can be obtained for scale-up and industrial applications; be designed and tested to quantify the effect of the hydrodynamic characteristics on the flotation results; have particular attention given to removal and control of the hard-to-quantify froth concentration phase; and allow minimum operator influence of results. The FLOTOMATEC design, developed and tested over the last five years, provides accurate measurements of air flow rate, energy consumption and agitation speed and eliminates most operator-induced errors. Froth is removed by constant-depth skimming with a conical-centred S-shaped skimmer. Extensive use of electronic instrumentation allows better control of operating parameters and complete knowledge of flotation conditions., Batch laboratory machines should: allow simple, reliable, reproducible operations; be sufficiently instrumented that measurements of physical and chemical parameters can be obtained for scale-up and industrial applications; be designed and tested to quantify the effect of the hydrodynamic characteristics on the flotation results; have particular attention given to removal and control of the hard-to-quantify froth concentration phase; and allow minimum operator influence of results. The FLOTOMATEC design, developed and tested over the last five years, provides accurate measurements of air flow rate, energy consumption and agitation speed and eliminates most operator-induced errors. Froth is removed by constant-depth skimming with a conical-centred S-shaped skimmer. Extensive use of electronic instrumentation allows better control of operating parameters and complete knowledge of flotation conditions.

A method has been devised to determine, by image analysis measurements and the use of mathematical transformations to reconstruct in three dimensions the information thereby obtained, the size distribution and proportion of components in composite particulate systems. The methods have been applied to characterise systems in which liberated ore particles occur together with composite particles of ore and gangue (middlings) in mixtures of complex sulphide ores., A method has been devised to determine, by image analysis measurements and the use of mathematical transformations to reconstruct in three dimensions the information thereby obtained, the size distribution and proportion of components in composite particulate systems. The methods have been applied to characterise systems in which liberated ore particles occur together with composite particles of ore and gangue (middlings) in mixtures of complex sulphide ores.

A mathematical solution to the problem of mineral liberation prediction is derived through the use of mathematical morphology and integral geometry methods. The solution is worked out for real particles produced by fragmentation of ores, and for ore textures which correspond to Boolean schemes with primary Poisson polyhedra and polyhedral textures., A mathematical solution to the problem of mineral liberation prediction is derived through the use of mathematical morphology and integral geometry methods. The solution is worked out for real particles produced by fragmentation of ores, and for ore textures which correspond to Boolean schemes with primary Poisson polyhedra and polyhedral textures.

The main features of a new reconstruction procedure for particle composition distribution from measurements on sections are presented. Two descriptors are used in this method, one function for particles and one for ore texture. Examples of applications of the method on iron ore and multiphase materials are discussed., The main features of a new reconstruction procedure for particle composition distribution from measurements on sections are presented. Two descriptors are used in this method, one function for particles and one for ore texture. Examples of applications of the method on iron ore and multiphase materials are discussed.

Pilot plant testwork on autogenous and semi-autogenous grinding was conducted to investigate the effect of ball addition, solids concentration in the feed, specific energy consumption and feed size distribution. A mathematical model that incorporates breakage and surface mechanisms of loss of mass was developed to predict load size distribution of autogenous and semi-autogenous mills. An empirical model was used to predict product size distribution of autogenous and semi-autogenous mills., Pilot plant testwork on autogenous and semi-autogenous grinding was conducted to investigate the effect of ball addition, solids concentration in the feed, specific energy consumption and feed size distribution. A mathematical model that incorporates breakage and surface mechanisms of loss of mass was developed to predict load size distribution of autogenous and semi-autogenous mills. An empirical model was used to predict product size distribution of autogenous and semi-autogenous mills.

It is concluded that turbulence and the presence of the froth layer are detrimental to the recovery of coarse particles during conventional flotation. A counter-current column cell is proposed to avoid these two factors. In this column, a net upwards flow of water is prevalent, such that no froth is allowed to form on the top. Also, the levitation of heavy bubble-particle aggregates is helped by the ascending water current. Preliminary work at laboratory level with kilogramme size samples indicated that under similar conditions recoveries in the column were much higher than in conventional cells. Flotation results obtained with coarsely sized phosphate and quartz samples are presented. One interesting feature of this type of column is very fast flotation kinetics. Thus, a short column (only 55 cm collection zone) yielded full recovery of floatable values., It is concluded that turbulence and the presence of the froth layer are detrimental to the recovery of coarse particles during conventional flotation. A counter-current column cell is proposed to avoid these two factors. In this column, a net upwards flow of water is prevalent, such that no froth is allowed to form on the top. Also, the levitation of heavy bubble-particle aggregates is helped by the ascending water current. Preliminary work at laboratory level with kilogramme size samples indicated that under similar conditions recoveries in the column were much higher than in conventional cells. Flotation results obtained with coarsely sized phosphate and quartz samples are presented. One interesting feature of this type of column is very fast flotation kinetics. Thus, a short column (only 55 cm collection zone) yielded full recovery of floatable values.

The reasons that explain the low recovery of coarse particles in conventional flotation are discussed. A flotation column modified according to the main conclusions of this discussion is tested with coarse phosphate samples., The reasons that explain the low recovery of coarse particles in conventional flotation are discussed. A flotation column modified according to the main conclusions of this discussion is tested with coarse phosphate samples.

The surface mechanisms of loss of mass for coarse particles in wet autogenous grinding was investigated in batch experiments using tumbling mills of 0.75 and 1.75m diameter. Measurements of wear were carried out by following the mass of individual particles. A simple model, based on a population balance analysis was used to compare predicted and actual load size distribution in continuous autogenous and semiautogenous pilot plant tests in the 1.75m diameter mill., The surface mechanisms of loss of mass for coarse particles in wet autogenous grinding was investigated in batch experiments using tumbling mills of 0.75 and 1.75m diameter. Measurements of wear were carried out by following the mass of individual particles. A simple model, based on a population balance analysis was used to compare predicted and actual load size distribution in continuous autogenous and semiautogenous pilot plant tests in the 1.75m diameter mill.