Optimisation of Operational Parameters of a Spiral Classifier Using Design of Experiment (DOE)

Abstract Classifying Mn Ore to improve upon the grade and the properties has become a crucial activity for the Mn industry since it increases the market value of the ore. Ghana Manganese Company (GMC) has renovated their oxide washing plant by integrating it with a spiral classifier to make a batch system operating process. Particle size of <3.35mm (Mn grade of 43-47%) obtained from the primary section of the plant served as feed to the classifier and with the plant condition (i.e. at 60 min washing time, 30 rev/min speed of spirals and feed tonnage of 6 t), Mn grade of 49% was achieved. This paper focused on the optimisation of some selected operational parameters of the classifier to obtain a Mn grade >50% using Design of Experiment (DOE). Series of test works were designed using the DOE for the classifier using the constraints of washing time (30-90 min), speed of spirals (20-40 rev/min) and feed tonnage (6-9 t). The outcome of the test work after simulation showed that all the selected parameters had a great influence on Mn grade. The spiral speed and feed tonnage correlated negatively to the Mn grade with washing time correlating positively. Operating the spiral classifier at a feed rate, spiral speed and washing time of 6 t, 25 rev/min, and 30 min, respectively, yielded Mn grade of 53%. A Confirmatory test using the established conditions gave a Mn grade of 53%, which is a 4% increment in the previous Mn grade which was 47%. The outcome of the studies is the new established operational conditions which is adhered to by the plant, producing a manganese concentrate grade ranging between 52-54%.   Keywords: Design of Experiment (DOE), Spiral Classifier, Grade, Manganes

Determining Acid and Metalliferous Drainage Potential of Waste Rock on a Mine

Acid and Metalliferous Drainage (AMD) is recognised as serious environmental problem in the mining industry. This is because environmental issue of AMD poses serious threat to water quality, vegetation cover and social licence of the mining operations. AMD occurs when reactive sulphide bearing materials are exposed to oxidising conditions. It has now become imperative for some mining companies to test sulphide bearing minerals for their AMD potential before major mining excavations are done. This work determines the AMD potential of fifty (50) waste rock samples from a Mine using Acid Base Accounting (ABA) techniques. Mineralogical studies on the sample indicated that the major sulphide mineral assemblages present were pyrite, arsenopyrite and chalcopyrite. Paste pH showed that 20% of the samples had undergone weathering and as such AMD generation had already started. Approximately 22% of the sample had conductivity levels between 1000 to 10,000 µS/cm and this shows a typical AMD chemical characteristic of high salinity. Acid Base Accounting showed that 32% of the samples were acid generating. Exactly 16% were non-acid forming and 52% were uncertain. The analysis showed that the potential for AMD generation exists for the waste rock material and can affect the local environment, specifically water quality if preventive measures are not taken.   Keywords: Sulphide, Waste Rock, Acid Base Accounting, Paste pH, Conductivit

Enhancing Parental Compliance in Managing Attention Deficit Hyperactivity Disorder

Medication adherence in children is essential in ensuring that treatment approaches are successful and lead to positive health outcomes for the patient. However, with the young child largely dependent on the abilities and drive of parents and caregivers, adherence to the treatment regimen for children diagnosed with attention-deficit/hyperactivity disorder (ADHD) can be challenging. A systematic literature review using the preferred reporting items for systematic reviews and meta-analysis (PRISMA) model was used to locate, analyze, and synthesize sources to identify current evidence-based strategies used by health care providers for enhancing parental compliance in managing the child with ADHD. Reported in themes, evidence-based strategies for enhancing parental compliance include family engagement, behavioral intervention strategies, pharmacological interventions, and specific healthcare provider strategies. This project will impact positive social change by providing evidence-based guidelines on best practices to help parents whose children are diagnosed with ADHD adhere to their medication and treatment regimen. Parental medication compliance also has the potential for improving ADHD symptoms such as impulsiveness, overactivity, and inattention and as such improve the child’s performance in school. Additionally, improved treatment compliance has the potential for reducing the number of hospital readmissions and visits to the emergency department. Last, if children with ADHD are managed effectively, they will grow to become productive members of society

Proxemics of screen mediation: engagement with reading on screen manifests as diminished variation due to self-control, rather than diminished mean distance from screen

Objective: Burgoon's theory of conversational involvement suggest that when people engage with a person, they will move slightly closer to them, often subtly and subconsciously. However, some studies have failed to extend this to human-computer interaction. Our hypothesis is that during online reading, engagement is associated with an expenditure of effort to hold the head upright, still and centrally. Method: We presented to 27 participants (ages 21.00 ± 2.89, 15 female) seated in front of 47.5x27 cm monitor two reading stimuli in a counterbalanced order, one (interesting) based on a best selling novel and the other (boring) based on European Union banking regulations. The participants were video-recorded during their reading while they wore reflective motion tracking markers. The markers were video-tracked off-line using Kinovea 0.8. Results: Subjective VAS ratings showed that the stimuli elicited the bored and interested states as expected. Video tracking showed that the boring stimulus (compared to the interesting reading) elicited a greater head-to-screen velocity, a greater head-to-screen distance range, a greater head-to-screen distance standard deviation, but not a further away head-to-screen mean distance. Conclusions: The more interesting reading led to efforts to control the head to a more central viewing position while suppressing head fidgeting

Experience design: video without faces increases engagement but not empathy

Counter to prior claims that empathy is required for higher levels of engagement in human-computer interaction, our team has previously found that, in an analysis of 844 stimulus presentations, empathy is sufficient for high engagement, but is not necessary. Here, we ran a carefully controlled study of human-computer interactions with musical stimuli --- with and without visuals, and with and without recognizable people -- to directly test whether we could design an engaging stimulus that did not elicit empathy, by avoiding human faces or personal interaction. We measured subjective responses by visual analogue scale and found that the faceless stimulus was as engaging as the face-containing stimulus, but much less empathy-provoking. Therefore, we propose that empathy and engagement be considered independently during interaction design, because they are not monotonically related

The complex relationship between empathy, engagement and boredom

In human computer interactions — especially gaming — the role of empathy has been mooted as a necessary prerequisite for higher levels of engagement and immersion. More recently other forms of engagement, including intellectual/cognitive engagement, have been proposed. In this study we present a carefully controlled dataset of human-computer interactions with a wide range of stimuli that ranged from highly engaging to boring to test these two theories. Analyzing 844 response sets to visual analogue scales (VAS) for empathy, interest, boredom, and engagement, we found that high empathy was sufficient for high engagement but is not necessary, whilst the converse was not true. We also found that empathy and boredom were incompatible with each other, but low levels of either were permissive rather than causal to the other. We conclude that there is no monotonic relationship between increasing empathy and engagement; either empathy is a sufficient (but not necessary) cause of engagement, or engagement is a necessary precursor to high empathy

Evaluation of the effects of Corchorus olitorius L. and Carapa procera in the treatment of obesity

Background: The obesity remains a pathology today which expands. It leads in its wake much pathology with very serious consequences. It is therefore necessary to take steps to curb this nutritional pathology. Thus, two plant species including Carapa procera and Corchorus olitorius have been tested to assess their effect on this pathology.Methods: Aqueous extracts of Carapa procera bark and Corchorus olitorius roots were tested on rats and biochemical parameters were evaluated. Besides, a chemical characterization was led.Results: These plant extracts contain bioactive molecules that have a regressive activity on the plasma levels of cholesterol, triglyceride and LDL-cholesterol. These bioactive molecules increase the level of HDL-cholesterol. These 2 species are non-toxic on renal, hepatic and pancreatic functions in view of the values of urea, creatinine and blood glucose.Conclusions: Of these 2 extracts, the aqueous extract of Corchorus olitorius is more active.

The environmental sustainability implications of contrast media supply chain disruptions during the COVID-19 pandemic: A document analysis of international practice guidelines

Introduction Travel restrictions implemented during the acute phases of the COVID-19 pandemic disrupted supply chain for critical radiology consumables including contrast media (CM) leading to shortages. Consequently, some departments had to restructure their clinical workflows in accordance to recommended guidelines to ensure safe continuity of patient care. This study aimed to summarise the temporary crisis-driven recommendations with implicit environmental sustainability essence and to analyse how these measures might inform the development of a more sustainable, long-term clinical guideline for safer and cost-effective CM usage without compromising diagnostic quality. Methods Documents were obtained through an electronic database search together with a relevant manual search in Google Scholar and relevant reference lists. The selected documents were subjected to a pre-defined eligibility criteria for inclusion. The READ approach was employed for document analysis and a thematic analysis of the obtained data was conducted. Results Of the 17 documents included, 70% (n = 12) emanate from the United States of America. The summary of the findings relate to minimising CM usage through strategic clinical approaches including optimisation of CM volumes, prioritisation of non-contrast imaging and/or alternative imaging depending on patient need without compromising diagnostic quality. Conclusion Critical lessons of sustainability essence are implicitly embedded in the policy guidelines issued during the periods of acute CM shortage in the COVID-19 pandemic. These lessons were themed around CM conservation based on: type and priority of medical imaging investigation, kind of imaging modality and use of smaller vials over multi-dose vials packaging. Implications for practice: The temporary crisis-driven strategies may offer critical lessons for post-pandemic service delivery to enhance patient safety while saving cost and promoting greener practice via strategic clinical and operational monitoring of CM through policy renewal, education and training and collaboration with industry partners

Antiretroviral Therapy during Tuberculosis Treatment and Marked Reduction in Death Rate of HIV-Infected Patients, Thailand1

Antiretroviral therapy is associated with a substantial reduction in deaths during TB treatment for HIV-infected TB patients