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- ItemEnergy Drink Consumption: Pattern and Effect on Commercial Drivers in Kumasi(KNUST, 2019-11) Pobee, Elizabeth LomokeiFor decades, the consumption of caffeinated beverages intended to “energize” has increased significantly. In Ghana, commercial drivers in major cities are rather at risk of daytime fatigue because of the many trips these drivers make to earn more money due to lack of regulation on the number of trips one makes in a day. Field observation shows that many commercial drivers rely heavily on energy drinks, however not much on this has been investigated. To address this, a cross sectional study was conducted on 210 commercial drivers across five taxi/bus stations in the Kumasi Metropolis. A structured questionnaire was used to collect demographic data and other information on the drivers’ pattern of energy drinks consumption. Five brands of energy drinks were sampled and analysed for presence of psychoactive agents such as benzodiazepines, cocaine, methamphetamine, opiates, tetrahydrocanobinoids and tramadol using the dip 6 test kit. HPLC was used to detect and quantify caffeine in the energy drinks and Atomic Absorption Spectrophotometer for detection of heavy metal contamination. The study showed the absence of the psychoactive agents’ benzodiazepines, cocaine, methamphetamine, opiates, tetrahydrocanobinoids and tramadol in the energy drinks. However, varying amounts of caffeine were detected in the energy drinks. The study also showed significant association between the number of trips and the number of bottles of energy drinks consumed (r = 0.631. p-value < 0.05). Hence, an increase in the number of bottles will cause an increase in the number of trips taken. The R square value 0.398 (~0.4) shows a 40% probability that consumption of energy drinks makes drivers make more trips. This result is desirable enough to lead drivers on to consume more energy drinks, thereby making them only go on long hours of drive while reducing their efficiency (by causing restlessness, insomnmia and confusion) as drivers on the road due to the cognitive changes of the psychoactive substance. Heavy metal iron was detected in all of the energy drinks tested, and copper in one of them, all below the allowed concentrations. In conclusion, this study showed a high consumption of energy drinks among the drivers with no regard to safety on our roads.
- ItemEffects of dopants on the conductivity of polyaniline Synthesized by chemical oxidation and electrochemical methods(KNUST, 2019-08-25) AWUAH, Joseph AsarePolyaniline salts (PANI-ES) were synthesized by chemical and electrochemical oxidation using primary dopants such as HCL, HNO3, H2SO4 and CH3COOH and the aniline as the monomer. All the synthesized PANI have resulted in emeraldine salts form as indicated by dark green colour of the salts. Various characterization techniques employed were UV-Visible spectroscopy, FT-IR and Cyclic voltammetery studies. All these techniques confirm the various properties of PANI. The characteristic bands in UV-Visible spectra of the samples indicate that effective doping has occurred in the synthesized polymer. Quinoid and benzenoid peaks at 1553-1596 cm- 1 and 1437 – 1496 cm-1 respectively were observed in all the samples. The band gaps for all the samples, both bulk and thin film, were obtained using the absorption spectra and Stern relation. PANI-H2SO4 had the least band gap for both bulk and thin film samples whereas PANI CH3COOH had the highest band gap. The voltammogram showed the various oxidation states during the electrochemical deposition at potential of 0.8 V. Four probe method was used to study the conductivity of both thin and bulk samples. The conductivity values for PANI-H2SO4 were found to be highest i.e. 1.183 S.cm−1 and 3.424 S.cm−1 for bulk and thin film respectively
- ItemEnergy Drink Consumption: Pattern and Effect on Commercial Drivers in Kumasi(KNUST, 2019-11) Pobee, Elizabeth LomokeiFor decades, the consumption of caffeinated beverages intended to “energize” has increased significantly. In Ghana, commercial drivers in major cities are rather at risk of daytime fatigue because of the many trips these drivers make to earn more money due to lack of regulation on the number of trips one makes in a day. Field observation shows that many commercial drivers rely heavily on energy drinks, however not much on this has been investigated. To address this, a cross sectional study was conducted on 210 commercial drivers across five taxi/bus stations in the Kumasi Metropolis. A structured questionnaire was used to collect demographic data and other information on the drivers’ pattern of energy drinks consumption. Five brands of energy drinks were sampled and analysed for presence of psychoactive agents such as benzodiazepines, cocaine, methamphetamine, opiates, tetrahydrocanobinoids and tramadol using the dip 6 test kit. HPLC was used to detect and quantify caffeine in the energy drinks and Atomic Absorption Spectrophotometer for detection of heavy metal contamination. The study showed the absence of the psychoactive agents’ benzodiazepines, cocaine, methamphetamine, opiates, tetrahydrocanobinoids and tramadol in the energy drinks. However, varying amounts of caffeine were detected in the energy drinks. The study also showed significant association between the number of trips and the number of bottles of energy drinks consumed (r = 0.631. p-value < 0.05). Hence, an increase in the number of bottles will cause an increase in the number of trips taken. The R square value 0.398 (~0.4) shows a 40% probability that consumption of energy drinks makes drivers make more trips. This result is desirable enough to lead drivers on to consume more energy drinks, thereby making them only go on long hours of drive while reducing their efficiency (by causing restlessness, insomnmia and confusion) as drivers on the road due to the cognitive changes of the psychoactive substance. Heavy metal iron was detected in all of the energy drinks tested, and copper in one of them, all below the allowed concentrations. In conclusion, this study showed a high consumption of energy drinks among the drivers with no regard to safety on our roads.
- ItemAssessment of microbiological and physicochemical quality of wastewater used for vegetable irrigation along the old waterworks stream in Tamale metropolis of Ghana(KNUST, 2018-06) Bashiru Nuhu, RabiWorldwide, several million hectares of farmland in estimated 50 countries are used to cultivate agricultural produce by farmers who have adopted the application of untreated and or partially treated wastewater from various sources. The application of untreated wastewater which are contaminated with microbes and chemicals including heavy metals poses serious public health threat on the vegetable farmers, vendors and consumers of vegetables cultivated using such untreated wastewater. This study assessed the microbiological, physical and chemical qualities of wastewater used for vegetable irrigation along the Tamale old waterworks stream in the Tamale Metropolis of Ghana. Two wastewater samples each were collected from the four sampling sites: Waterworks upstream (WWU), Gumbihini midstream (GMS), Nyanshagu midstream Gardens (NMS) and Tunayili Kulbong Downstream Gradens (TKDS) along the stream monthly for six consecutive months for microbial and physicochemical parameters for dry and rainy seasons. A total of forty-eight water samples were collected and analysed for their microbiological, chemical and physical qualities using standard protocols adopted by the American Public Health Association (APHA, 1998). The results obtained showed consistent increase in the bacterial and physicochemical load for both irrigation seasons. The bacterial parameters studied include total coliform, faecal coliform, E. coli, Staphylococci, Enterococci, Pseudomonas and total heterotrophic bacteria. The statistical analysis on the microbials gave a weak correlation (r=0.24) among the individual sampling sites for microbial statistics. More so, there is a significant difference between the wastewater samples for dry and rainy season irrigation of microbial parameters with (p = 0.005) from the pairwise sample test. Results obtained showed consistent increase in the bacteria load for both seasons with the rainy season recording higher loads than the dry season except for total heterotrophic bacteria which was rather higher in the dry season as compared to rainy season. Overall, bacterial count recorded was lowest at GMS1 and highest at NMS2 for both seasons. The physicochemical parameters include, pH, conductivity, total alkalinity, total hardness, calcium hardness, magnesium hardness, carbonate hardness, bicarbonate hardness, calcium, magnesium, chloride, fluoride, sulphate, sulphide, phosphate, ammonia-nitrogen, nitrate-nitrogen, nitrite-nitrogen, aluminium, total iron, manganese, copper, zinc, cyanide, total chromium and potassium. There is strong correlation (r=0.99) among the individual sampling sites for physicochemical parameter analysis of wastewater samples during dry and rainy season irrigation schemes. More so, pairwise analysis indicates that there is no significant difference (p= 0.41) among the sampling sites for physicochemical wastewater samples for dry and rainy season irrigation of physicochemical parameters. Overall, physicochemical values recorded were lowest at GMS1 and highest at NMS2 for both the dry and rainy season samples. More so, bacterial counts recorded for all the microbial parameters exceeded the WHO (2006b) guideline of 1x103cfu/100ml for unrestricted irrigation of crops likely to be eaten raw whilst the physicochemical parameters determined were found to be within FAO/WHO guidelines for irrigation water except for colour, total alkalinity, chloride, zinc and cyanide. Most of the chemicals had levels above WHO guidelines and are potential health threat especially high nitrate concentration in irrigation water causes blue baby syndrome. The application of untreated wastewater poses serious public health threat on the vegetable farmers, vendors and consumers of vegetables cultivated using such untreated wastewater. It is therefore recommended that wastewater for irrigation of ready-to-eat vegetables be treated using biological nutrient removal system and wastewater stabilisation ponds to reduce and or eliminate contaminants before irrigating vegetables.
- ItemThe scalability metric, based on cost-effectiveness in distributed systems using fundamental laws(KNUST, 2018) Gyasi Emmanuel KwabenaToday’s computer systems are more complex, more rapidly evolving, and more essential to the conduct of business than those of recent past. The complexity becomes more rigid in the case of distributed systems. A distributed system is a collection of independent computers that appear to its users as a single coherent system. A distributed system should be deployable in a wide range of scales, in terms of numbers of users and services, quantities of data stored and manipulated, rates of processing, numbers of nodes, geographical coverage, and sizes of networks and storage devices. The derived scalability metric of this thesis is based on cost effectiveness, in which the effectiveness is a function of the system's throughput and its Quality of Service. It is a strategy based scalability metric that generalizes the well -known metrics for scalability of parallel computations to describe heterogeneous distributed systems. Scalability is measured by the range of scale factors that gives a satisfactory value of the metric, since a good scalability is a joint property of the initial design and the scaling strategy. What makes this derived metric unique is the fact that, it separates the impact of throughput and response time on the metric, formalizing the notation of a scaling strategy, introducing QoS evaluation and more also, introducing formal scalability enablers which are optimized at each scale factor. Throughput curves for all systems with bottleneck demand 𝐷𝑚𝑎𝑥 are constrained to lie below the line 1𝐷𝑚𝑎𝑥⁄. If one needs to improve the performance further than this limit, then it is necessary to reduce the demand at the bottleneck center somehow.