Showing papers in "Ghana journal of science in 2020"

Phosphomolybdenum Blue Detection – A Review of Characteristics, Achievements, Challenges and Future Prospects

Abstract: Phosphate detection in the environment (especially, water bodies) is very essential in view of its consequent pollution effects on eutrophication. Continuous monitoring of phosphate concentration (and phosphorus compounds in general) in water samples has been based on phosphomolybdenum blue formation coupled with spectrophotometric detection. Continu­ous flow injection analyses (FIA) are well known to present numerous advantages over batch methods. Furthermore, the development of on-chip micro-channel analytical (μFIA) systems begun and have gained much attention within the last two decades in view of the striking advantages over conventional FIA techniques. This paper reviews published information on detection of phosphomolybdenum blue in conventional systems as well as on micro-chip. It reports on the challenges encountered (interference from other complex anions), the achieve­ments made so far (intereference removal by electrokinetic separation) and what the future holds (simultaneous determination).

PAH Quantification and Estimated Carcinogenic Risks at Selected Fuel Stations in Tamale Metropolis, Ghana

Abstract: The research aim was to quantify PAHs levels and assess their associated carcinogenic health risks in fuel filling stations located in both high and low vehicular traffic areas in the Tamale Metropolis of Ghana. Dust particles were collected from ten fuel filling stations and extracted using an Accelerated Solvent Extractor (ASE). PAH analysis was conducted using a GC-MS system. Cancer risk assessment was done using the Incremental Life-time Cancer Risk (ILCR) model. The average PAH concentration recorded in the high and low vehicular traffic areas were 158,080±102,650 μg/kg and 370,220±218,140 μg/kg respectively. Benzo(a)Anthra­cene was the most occurring PAH congener recorded in both traffic areas. Dermal contact as a route of PAH exposure recorded the highest potential cancer risk for both adults and children. Amongst the fuel filling stations, Gab Energy recorded the highest carcinogenic risks of 2.50 (adults) and 2.67 (children). In all, the average cancer risk values for adults (1.02) was slightly higher than that of the children (9.26E-01) with no significant difference. The mean ƩILCR val­ues for both populations indicated a high to very high potential carcinogenic risk to the people living or working in and around the study areas.

Estimating the Returns to Schooling: A Comparison of Fixed Effects and Selection Effects Models for Twins

Abstract: Strong empirical links exist between the number of years spent schooling and earnings. How­ever, the relationship may be masked due to the effect of unobserved factors that influence both wages and schooling. Two of the main econometric models, namely fixed-effects and se­lection-effects, used to analyse returns to schooling were compared using monozygotic and di­zygotic twins’ datasets in Ghana. The efficiency of the models was assessed based on the stan­dard errors associated with the return to schooling estimates. Goodness of fit measures was used as a basis for comparison of the performance of the two models. The results revealed that based on their standard errors, the regression estimates from the selection effects model (MZ = 0.1014±0.0197; DZ = 0.0947±0.0095) were more efficient than the regression estimates from the fixed-effects model (MZ = 0.1115±0.0353; DZ = 0.082±0.0127). However, the AICc values of the fixed effects model (MZAICc = 57.8 and DZAICc = 105.4) were smaller than the AICc values of the selection effects model (MZAICc = 151.6 and DZAICc = 221.6). Findings from the study indicate that, although both models produced consistent estimates of the economic returns to schooling, the fixed effects model provided a better fit to the twins’ data set.

Effects of Single Bout and Short Term Aerobic Exercise on C-Reactive Protein in Type-2 Diabetes Patients: A Pilot Study

Abstract: Type-2 diabetes is a leading risk for cardiovascular diseases and events due to ease of develop­ment of atherosclerosis in people with type-diabetes. Chronic inflammation is a major driver of atherosclerosis in type-2 diabetes and it has been linked to elevated C-reactive protein (CRP) level. The objective of this study was to determine whether CRP is amenable to aerobic exercise. A total of 40 adults diagnosed with type-2 diabetes patients were sampled randomly, and later, conveniently allocated into exercise and control groups. All the subjects were on the diabetes exchange diet as recommended by their Dieticians. Results show that the glucose level of the subjects of this study was fairly under control ((glycated haemoglobin (HbA1c) = 0.80±0.11% for each of the group)). A weak negative correlation was found between ex­ercise-induced reductions in CRP and HbA1c (r = -0.345; p = 0.029). Significant (p 0.05) difference in CRP was found between study and control groups after 8-weeks. Single bout or short-term aerobic exercises does not reduce CRP in people with fairly controlled type-2 diabetes mellitus.

Quantification and Removal of Trichloromethane in Chlorinated Water Using Coconut Shell Activated Carbon

Abstract: Commercially, available activated carbon (CAC) and coconut shell activated carbon (CSAC) were used in the adsorption of Trichloromethane (TCM) from disinfected water using the optimum conditions (concentration, dosage, pH and time) obtained. Concentrations of TCM were determined using GC-MS. Physicochemical parameters of CSAC were investigated. The CSAC gave percentage carbon yield (86.72±1.41), surface area 1200 m2/g and CHNS/O Elemental Analyzer gave elemental Carbon of 60.08% as the highest of the elements in the char. A pore structure dispersed on the CSAC surface was observed. Best conditions for CSAC were: 1.4 × 104μg/l TCM, 5.0 pH, 0.8 g absorbent within 30 minutes. The data fitted Freundlich than Langmuir model (R2 of 0.9977 and 0.9232, respectively). Percentage removal of TCM for CAC and CSAC was 98.3±1.55 and 96.7±1.27, respectively for the water sample. Results indicated that CSAC was efficient for removal of TCM present in water and could be used as alternative for CAC in water treatment.

Road Use Behaviour of Urban Primary School Children in Ghana: Case Study of Ablekuma South Education Circuit of Metropolitan Accra

Abstract: School children form majority of injured children on Ghanaian roads. The objective was to observe the road use behaviour of public primary school pupils in Ablekuma Education Circuit, Accra. This unobtrusive observational study targeted Primary one to six pupils. Five behaviours were studied: Walking while crossing road; Stopping at the kerb; Looking left-right-left before crossing; Keep looking left-right-left while crossing and Facing traffic while walking. 882 pu­pils on their way to or from school were observed from eight schools. A little over two in three children stopped at the kerb before crossing the road while almost three in four children looked for cars before stepping off the kerb. A little over three in four children walked while crossing and less than one in four children kept looking while crossing. Not looking for cars before crossing, not facing on-coming traffic and not keeping looking for cars while crossing, were more associated with boys than girls (p < 0.001; 95%CI in all cases). Girls behaved significant­ly more safely than boys. In stopping at the kerb, there was no difference in gender behaviour (p < 0.135; 95%CI). Child Road Safety Education in Schools and Communities is recommended.

Detection of Human Genotype “B” Giardia lamblia in Ghanaian Cattle from Frafraha in Adentan Municipality of Ghana

Abstract: Giardia duodenalis is a common intestinal parasite in humans, a wide range of domesticated and wild animals. There are human and animal specific, as well as zoonotic pathogenic gen­otypes. It is not clear whether livestock in close proximity to humans could be infected with human specific genotypes, and vice versa. In this study, Giardia-positive faecal samples were collected from both humans (n = 4) (from Maamobi Polyclinic in the Ayawaso Sub- Metro) and calves (n = 8) (from Animal Research Institute Farms, Adentan Municipality), in Ghana. Nested PCR amplification using Giardia-specific, Glutamate dehydrogenase (GDH) genes and Tri­osephosphate isomerase (TPI) gene primers for human and animal faecal samples respectively was carried out. Results showed that 100% of the calves carried the TPI-B genotype, which is a common pathogenic genotype in humans. This report is based on the unusual results obtained as Giardia duodenalis genotype B is known to occur in humans but is being observed in calves for the first time. This suggests that calves in close proximity to humans could be reservoirs and sources of human Giardia infections.

An Experimental Assessment of Lifi Data Communication

Abstract: In this paper, two functional light fidelity real-time testbeds implemented on custom Light fidelity (LiFi) kits are presented. This paper evaluates the use of LiFi technology over differ­ent distances and angular placement of illuminating devices and endpoint transceivers with connectivity locally and to the internet. The objective is to determine if distance or angular positioning in LiFi influence speeds or not. Finally, it aims to contribute to knowledge in the LiFi communication domain. We were limited to developing a customized testbed for wireless optical communication by accessing data in the physical layer via photons. In a lateral dis­tance and angular position, we examined the performance of a laptop with LiFi activated by a 3730 lm LED. The setup evaluated the performance of our design in a downlink and uplink scenario where the transmitter was embedded in the main LED unit and the laptop was used as a photoreceiver. The data rate/kbps, the lateral distance / m, and the angle displacement / θ° were the comparison metrics. The results of the tests show that the transmission of LiFi is not influenced by distance and angular positioning for both downloads and uploads over different distances.

The Ghana Highway Code as a Teaching and Learning Material

Abstract: The Ghana Highway Code is the official state-recognised traffic teaching and learning ma­terial widely used in traffic schools and by motorists in Ghana. Ghana changed its traffic from left-hand to right-hand drive in 1974; the Code was subsequently published to, besides other reasons, guide road users to be reconditioned to a fresh standard of behaviour. However, 46 years after its publication, the content of the Code has been outgrown by new developments in the road environment and traffic systems, rendering the Code ineffective. Content analysis was used to ascertain the validity and reliability of the Code. Out of 95 mo­torists interviewed, 91.5% indicated they use or had ever used the Code, while 3.2% had not used it before and 5.3% did not know about it at all. Hundred percent of driving schools used the Code as teaching and learning material. It was concluded that the Code was an obsolete teaching and learning material. The implication was that, the wide user population of the Code had an adverse impact on learners. It was recommended that the Code be revised and republished as new edition.