Impact of Urban Effluents on the Macroinvertebrates of a Creek in Accra, Ghana

The impact of effluents on the macroinvertebrate communities of an urban creek in Accra was studied. Five study stations were selected along the reaches of the creek. Water and benthic samples were collected and analyzed between September 2005 and February 2006. The study showed that the effluent discharges caused a significant increase in BOD, COD and NH3 at the stations that received the effluents. The high levels of total and faecal coliforms at the midstream sections of the creek (626.0 x 104 cfu/100 ml and 75.30 x 104 cfu/100 ml, respectively) indicated increased pollution levels compared to the reference stations (446.0 x 103 cfu/100 ml and 133.0 x 103 cfu/100 ml). The Nima Creek showed characteristics of a disturbed urban creek. A total of 19 macroinvertebrate taxa, comprising a total of 11,613 individuals, were collected. Estimated Shannon-Weiner Diversity Index (H´) was low at the midstream section of the creek, H’= 1.14, where the effluents were concentrated than at the upstream H’=1.44 or downstream H’= 1.38 sections of the creek. Chironomini and Physa were the most abundant taxa within the creek, dominated by the genus Chironomus, which is known to be tolerant to pollution, which confirmed the polluted state of the creek. Rigorous and regular assessment and monitoring of effluents from waste treatment plants and other sources that discharge into the creek, with the aim of complying with the Environmental Protection Agency (EPA) guidelines are some of the mitigative measures suggested to protect life in the creek

Christology and Evil in Ghana: Towards a Pentecostal Public Theology

Wit, J.H. de [Promotor]Vroom, H.M. [Promotor

An epidemiological study of recent outbreaks of Gumboro disease in Ghana

A study to assess the epidemiological factors responsible for the recent outbreaks of infectious bursal disease (IBD) in Accra and Kumasi, between October and December 2002 and January to April 2003, was conducted. Case report records at Veterinary Diagnostic Laboratories were examined for IBD cases. Farm investigations were carried out using a combination of questionnaire and interviews to obtain information on the disease situation on farms, where the outbreaks had occurred. The highest occurrence of the disease was recorded between March and April 2003, with Accra showing the highest number of cases in March, coinciding with the Easter season. Day-old chicks imported into the country succumbed more easily to the disease than those produced locally. There was an association between IBD and the chicken type that was significant (P < 0.05) in cockerels and layers. Chickens vaccinated twice were more likely to be protected from the disease than those not vaccinated or vaccinated only once. The prevalence of the disease was also influenced by the age of the chickens with a rise in susceptibility with age from 3 weeks to 6 weeks old. The results of the study indicate that the factors studied, namely source of day old chicks, bird type, vaccination history, and age of chicks at the time of outbreak influenced outbreaks of IBD and are likely to contribute to the endemicity of infectious bursal disease in the poultry producing areas of Ghana. It is recommended that stringent biosecurity measures be observed on poultry farms to control the disease in the country

Emollient prescribing formularies and guidelines in England, 2021:a cross-sectional study.

BACKGROUND: Emollients are a mainstay of treatment for dry skin conditions. In the UK, prescribers are usually expected to follow local National Health Service (NHS) formularies. A previous study in 2018 showed that the recommended emollients across England and Wales varied widely. Evidence has since emerged that bath additives provide no additional clinical benefit in eczema. AIM: To compare emollient formularies and guidelines in England. METHODS: Clinical Commissioning Group (CCG) formularies and guidelines were identified in April–May 2021, compiled and then analysed descriptively. RESULTS: In total, 105 CCGs, 72 emollient formularies and 47 emollient prescribing guidelines were identified. There were internal inconsistencies between formularies and their accompanying guidelines in 19% of cases. The majority (68%) of formularies/guidelines were organized using a ranking system. In total, 126 different leave‐on emollients were named. Creams and ointments were universally available and were the most recommended first‐line types. Cost was more likely than patient choice to be recommended as a criterion for selecting which emollient to prescribe. Aqueous cream was the leave‐on emollient most commonly not recommended. Nearly three‐quarters (74%) of formularies stated that bath additives should not be prescribed. CONCLUSION: All CCGs in England have an emollient formulary/guideline, but there is still great variability between them in their recommendations. Although the number of formularies/guidelines has reduced since 2017, there has been an increase in the total number of unique recommended leave‐on emollients. Most CCGs are no longer recommending bath emollients for eczema

Isolation and characterization of infectious bursal disease virus (IBDV) field strains and pathotypes in Ghana

Isolation and characterisation of Ghanaian field IBD virus were undertaken as part of a comprehensive study to establish an efficacious vaccination programme against the disease in the country. Bursal homogenates wereprepared from chickens that died of IBD in five different locations of the country. Batches of 11-day-old Specific Antibody Negative (SAN) embryonating eggs were inoculated with 0.2 ml of homogenate each on the chorioallantoic membrane. The eggs were incubated and candleddaily, and all embryonic deaths were examined for gross IBD lesions. In addition, batches of 3-week-old SAN chickens were inoculated intra-occularly with 10 &mu;l of the bursal homogenate and observed over 10 days for clinical signs and gross lesions of IBD. Pathotyping of the virus isolates was done by the biological method, using groups of 10, 6-week-old SAN chickens and confirmed by the reverse transcriptase-polymerase chainreaction-restriction fragment length polymorphism (RTPCR- RFLP) technique. Embryos inoculated with homogenates from all five locations died 3 to 5 days pest inoculation (PI), showing characteristic IBD lesionsof extensive haemorrhages, congestion of limbs and stunted growth. Inoculated 3-week-old SAN chickens showed 100 per cent cumulative mortality, enlarged haemorrhagic and oedematous bursae, and haemorrhages in the breast and thigh muscles. Six-week-old SANchickens inoculated with bursal homogenates showed similar lesions. One isolate LV/G19 selected and standardized for viral challenge studies had an ELD50 value of 106.3. The SAN chickens challenged with thisisolate were more susceptible between the ages of 3 and 6 weeks, but morbidity and mortality were seen up to 10 weeks of age. This study confirms the presence of the very virulent Infectious Bursal Disease Virus (vvIBDV) in Ghana and the urgent need for its control

Mechanical properties and microstructure of fibre-reinforced clay blended with by-product cementitious materials

Clayey soils endure adverse changes in strength and volume due to seasonal changes in moisture content and temperature. It has been well recognised that high cement content has been successfully employed in improving the mechanical properties of clayey soils for geotechnical infrastructural purposes. However, the environmental setbacks regarding the use of high cement content in soil reinforcement have necessitated the need for a greener soil reinforcement technique by incorporating industrial by-product materials and synthetic fibres with a reduced amount of cement content in soil-cement mixtures. Therefore, this study presents an experimental study to investigate the mechanical performance of polypropylene and glass fibre-reinforced cement-clay mixtures blended with ground granulated blast slag (GGBS), lime and micro silica for different mix compositions and curing conditions. The unconfined compressive strength, linear expansion and microstructural analysis of the reinforced soils have been studied. The results show that an increase in polypropylene and glass fibre contents caused an increase in unconfined compressive strength but brought on the reduction of linear expansion of the investigated clay from 7.92% to 0.2% at fibre content up to 0.8% for cement-clay mixture reinforced with 5% Portland cement (PC). The use of 0.4–0.8% polypropylene and glass fibre contents in reinforcing cement-clay mixture at 5% cement content causes an increase in unconfined compressive strength (UCS) values above the minimum UCS target value according to American Society for Testing and Materials (ASTM) 4609 after 7 and 14 days curing at 20◦ C to 50◦ C temperature. Therefore, this new clean production of fibre-reinforced cement-clay mixture blended with industrial by-product materials has great potential for a wide range of applications in subgrade reinforcement

Consistency and mechanical properties of sustainable concrete blended with brick dust waste cementitious materials

The reuse of waste materials in civil engineering projects has become the topic for many researchers due to their economic and environmental benefits. In this study, brick dust waste (BDW) derived from cutting of masonry bricks and demolition waste which are normally dumped as land fill is used as partial replacement of cement in a concrete mix at 10%, 20% and 30% respectively, with the aim of achieving high strength in concrete using less cement due to the environmental problems associated with the cement production. To ascertain the effects of BDW on the consistency and mechanical performance of concrete mix, laboratory investigations on the workability of fresh concrete and the strength of hardened concrete were carried out. Slump and compaction index test were carried out on fresh concrete mix and unconfined compressive strength (UCS) test and tensile strength test were conducted on hardened concrete specimen after 7, 14 and 28 days of curing. The results showed high UCS and tensile strength with the addition of 10% BDW to the concrete mix, hence achieving the set target in accordance with the relevant British standards. A gradual reduction in strength was observed as BDW content increases, however, recording good workability as slump and compaction index results fell within the set target range in accordance with relevant British standards. Findings from this study concluded that BDW can partially replace cement in a concrete mix to up to 30% igniting the path to a cleaner production of novel concrete using BDW in construction work

Road pavement thickness and construction depth optimization using treated and untreated artificially-synthesized expansive road subgrade materials with varying plasticity index

Road pavement thickness and their depth of construction take a chunk of the overall cost of road construction. This has called for a need for reduced road pavement thickness by improving the engineering properties of subgrade such as the California bearing ratio (CBR). The CBR of road subgrade has been a major determining factor for road pavement thickness, and expansive subgrades generally have a low CBR, resulting in major road defects. In this study, road pavement thickness and construction depth optimization were conducted using the CBR values achieved in this study. Additives proportions of 8% lime and 20% cement were used in expansive subgrade to improve their engineering properties, making them suitable for use in road construction. The study investigated the characteristics, mineral structure, Atterberg limit, compaction, CBR, swell and microstructural properties of expansive subgrade. The results show a reduction in road pavement thickness and a construction depth with an increase in CBR value. All CBR values for treated samples were above 2%, making them usable in road construction. A reduction in swell potential up to 0.04% was observed for treated expansive subgrade. The study concluded that pavement thickness and construction depth can be reduced by enhancing subgrade materials and using cement and lime as binders

Enhancing the engineering properties of subgrade materials using processed waste: A review

Subgrade materials refer to the original ground underneath a road pavement, when these materials are made up of expansive soil it is referred to as expansive subgrade. Sometimes, these materials do not have sufficient capacity to support the weight of the road pavement and traffic load, which means they require some form of modification and re-engineering to enhance their load capacity. Chemical modification techniques using traditional stabilisers (such as cement and lime) have proved to be an effective means of subgrade stabilisation. However, high costs and environmental concerns associated with the use and production of these additives have highlighted the need for more sustainable and environmentally friendly substitutes. This study reviews the use of industrial by-products and other waste materials used for subgrade stabilisation, focusing on the sustainability of using processed wastes and how they alter the engineering properties of weak subgrade, compared to the use of cement and also reviews the availability of processed waste materials in quantities sufficient to meet the current demand for subgrade stabilisation. The findings illustrate that, processed waste is less expensive and has better sustainability credentials compared to cement. Moreover, processed wastes are available in sufficient quantities to meet existing demands for subgrade stabilisation. Therefore, it is recommended that the use of processed wastes should be promoted and utilised to improve and enhance the geotechnical properties of weak subgrade materials where possible

Propagating the fear of witchcraft: Pentecostal prophecies in the new prophetic churches in South Africa

Pentecostal prophecy is one of the major themes of the theology and practice of religion among the prophets of New Prophetic Churches in South Africa and a major factor to the growth and expansion of Pentecostalism in Southern Africa. This paper offers a reflection on the role of prophecy in relation to the fear of witchcraft in the region. The contribution is that Pentecostal prophecy is not always in confrontation but sometime propels the fear of witchcraft. Through media analysis, the paper illustrates with some examples of Pentecostal prophecies on witchcraft how Pentecostal prophecy can aid rather than dispel fear of witchcraft. These prophecies raise several challenges to the discernment of Pentecostal prophetic ministry.Christian Spirituality, Church History and Missiolog