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This study explored the potential of three local microalgal isolates as feed for oyster larvae in laboratory‐rearing experiments, towards the optimisation of seed production of Crassostrea tulipa to support its large‐scale farming along the West African coast. Three species of local microalgae—Rhodomonas sp., Nannochloropsis sp. and Pseudanabaena sp.—were isolated from waters off the coast of Ghana, West Africa, following a serial dilution technique. The growth performance of the isolates was assessed in the laboratory through daily estimation of cell density until the stationary phase was observed. Characterisation of the microalgal isolates was carried out by estimation of their biovolume, carbon content and energy content. Biovolumes of the microalgae were calculated from the estimated equivalent spherical diameters using proposed geometric shapes and formulae. Carbon weight and carbon energy content were subsequently calculated using derived conversions. The three microalgal isolates showed potential for large‐scale cultivation in the laboratory with marked differences in daily increases in cell densities. Nannochloropsis sp. and Rhodomonas sp. recorded the highest and the lowest peak densities of 2.4 × 105 and 1.5 × 105 cell mL−1, respectively, from an initial inoculating cell density of 1.05 × 105 cell mL−1. The estimated mean biovolumes of Rhodomonas sp., Nannochloropsis sp. and Pseudanabaena sp. were 238.9, 8.182 and 42.42 µm3, respectively, and the corresponding derived carbon energy contents were 1.7 × 10−6, 7.13 × 10−8 and 1.05 × 10−7 J, respectively. Results from a laboratory rearing experiment indicated that the individual microalgal isolates supported the growth and survival of oyster larvae at different scales, but a mixed diet of the three promoted superior growth and survival of C. tulipa larvae. The three local microalgal isolates‐ Rhodomonas sp., Nannochloropsis sp., and Pseudanabaena sp.‐ were well adapted to laboratory culture conditions, and the observed differences in growth and survival of the oyster larvae fed on these algal diets could be due to the differences in diet properties and biochemical compositions of the different species. A combination of the three algal diets, however, provided complementaery nutrients for the optimal growth and survival of C. tulipa larvae. The outcome of this study shows that local microalgal isolates have the potential to support hatchery rearing of C. tulipa, which is essential for the development of commercial mangrove oyster aquaculture in West Africa. [ABSTRACT FROM AUTHOR]

Acute toxicity of raw and treated greywater towards Daphnia magna was assessed in this study. Treatment was performed with exposure of greywater to the fly-lime mixture After 48 h of exposure, 100 % mortality of D. magna was recorded when testing the following volumetric fractions of the raw greywater streams in the tested liquid medium (%; v/v): 10 % for kitchen greywater, 5 – 10 % for bathroom greywater and 1.25 – 10 % for laundry greywater. After greywater treatment with the fly-ash-lime mixture with pH adjustment to 7.0, 80 % of neonates of D. magna survived after exposure to treated laundry greywater in all dilutions at 48 h. At the same time, 100 % of neonates survived exposure to treated bathroom and kitchen greywater at all volumetric fractions. Therefore greywater had acute toxicity to D. magna, i.e. greywater treatment was required before its discharge or reuse. Values of the Pearson’s correlation coefficient between the chemical components of the raw greywater and treated greywater and the survival of D. magna indicated a lack of statistically significant correlation at 5 % level of significance (p-value > 0.05 in all cases), i.e. the survival of D. magna was independent of the concentration of chemical constituents in greywater samples tested. Further studies will have to be conducted on the chronic toxicity of the greywater effluent after treatment with the fly-lime mixture. Experiments from this study will have to be re-run for the fully scaled-up version of the fly-lime mixture-based greywater treatment systems.

Beach seine fishery provides a means of livelihood to many households in Africa and it is widely practiced in the coastal communities of Ghana due to the relatively cheaper operational cost. However, the small mesh sizes of beach seine nets and fishing activities that involve dragging a net through the nearshore seabed tend to destroy fish breeding grounds and capture juvenile fish and non‐target benthic macroinvertebrates, which get discarded. This study investigated the impact that before and after closed season for beach seine fishing had on macroinvertebrates species diversity indices at two Ghanaian beaches with different fishing pressures. The study was carried out at OLA and Sisimbo Beaches located in the Central Region of Ghana, taking advantage of the statutory 1‐month national fishing closed season in July 2022. Six (6) replicate sediment samples were taken at each beach after landing by beach seine fishers every month for 6 months, from April to June, and August to October, representing before and after closed season, respectively. Benthic macroinvertebrates were retrieved from the samples using appropriate protocols and subjected to indirect (Shannon, Simpson, Rényi) and direct (species abundance models, species accumulation models, multivariate statistics) measures of species diversity analyses. The indirect species diversity indices increased monotonically the following 2 months after closed season but reduced in the third month after closed season at both beaches. Conversely, the direct measures of diversity indices revealed that closed season for beach seine fishing improved species numbers and richness at both study beaches. This is the first report on the impact of a closed season on macroinvertebrates in any African country. [ABSTRACT FROM AUTHOR]

Climate change is a global threat that is better understood through global research spanning many regions, countries, and life-supporting ecosystems. This review focused on the bibliometric analysis of the distribution of a global research compendium on phytoplankton, an aquatic community that accounts for half of the carbon fixation in the global carbon cycle. A total of 716 primary research papers published in the immediate past decade (2012–2022) were reviewed. The articles were sampled from Web of Science and described field and laboratory experiments quantifying the impact of global climate change on phytoplankton from different climate zones (tropical, subtropical, temperate, subpolar, and polar) and ecosystems (freshwater, brackish, and marine). Analyses of these studies suggest that the bulk of the global research effort (80%) focused on high-latitude areas, and only a few (17%) were carried out in the tropics, largely led by four countries (Australia, Brazil, India, and Saudi Arabia), while Africa's contribution was minuscule (<1%). In terms of ecosystems, the majority (76%) of the research was in marine waters, irrespective of the climate zone. Analyses of these studies also highlighted widespread disparities in phytoplankton research in tropical aquatic ecosystems, particularly in Africa. Strategic investment in terms of targeted funding, institutional networks, and partnerships between the global north and global south are necessary to increase phytoplankton research across different ecosystems in the tropics. [ABSTRACT FROM AUTHOR]

A Water Quality Index (WQI) is a tool that describes the overall water quality by combining complex and technical water quality information into a single meaningful unitless numerical value. WQIs predict water quality since they reflect the impact of multiple Water Quality Parameters (WQPs) and allow for spatial-temporal comparison of water quality status. Most African countries employ adapted WQIs by modifying the original index (or indices) and propose their concepts for evaluating the quality of surface and groundwater, which is normally accompanied by irregularities. The current review examined the process(es) involved in WQI modifications for monitoring water quality in Africa, explored associated limitations, and suggested areas for improvement. A review of 42 research articles from five databases in the last ten years (2012–2022) was conducted. The findings indicated Weighted Arithmetic (WAWQI) and the Canadian Council of Ministers of Environment (CCMEWQI) as the most adapted WQIs. However, several limitations were encountered in WQI developmental steps, mainly in parameter selection and classification schemes used for the final index value. Incorporation of biological parameters, use of less subjective statistical methods in parameter selection, and logical linguistic descriptions in classification schemes were some recommendations for remedying the limitations to register the full potential of adapted WQIs for water quality monitoring in Africa. [ABSTRACT FROM AUTHOR]

Satellite cells are required for muscle regeneration, remodeling, and repair through their activation, proliferation, and differentiation; however, how dietary factors regulate this process remains poorly understood. The L-type amino acid transporter 1 (LAT1) transports amino acids, such as leucine, into mature myofibers, which then stimulate protein synthesis and anabolic signaling. However, whether LAT1 is expressed on myoblasts and is involved in regulating myogenesis is unknown. The aim of this study was to characterize the expressional and functional relevance of LAT1 during different stages of myogenesis and in response to growth and atrophic conditions in vitro. We determined that LAT1 is expressed by C2C12 and human primary myoblasts, and its gene expression is lower during differentiation (P < 0.05). Pharmacological inhibition and genetic knockdown of LAT1 impaired myoblast viability, differentiation, and fusion (all P < 0.05). LAT1 protein content in C2C12 myoblasts was not significantly altered in response to different leucine concentrations in cell culture media or in two in vitro atrophy models. However, LAT1 content was decreased in myotubes under atrophic conditions in vitro (P < 0.05). These findings indicate that LAT1 is stable throughout myogenesis and in response to several in vitro conditions that induce muscle remodeling. Further, amino acid transport through LAT1 is required for normal myogenesis in vitro. [ABSTRACT FROM AUTHOR]

We assessed the influence of Azotobacter inoculated commercial compost on eggplant productivity and soil nutrient status in the semi-deciduous forest zone of Ghana. In randomized complete block design, eight treatments (Control, 2.5 t ha−1 compost, 5 t ha−1 compost, 100% recommended NPK fertilizer at 50 kg N, 30 kg ha−1 P2O5 and 30 kg ha−1 K2O, 2.5 t ha−1 compost+50% NPK, 5 t ha−1 compost+50% NPK, 50% NPK and 2.5 t ha−1 compost+100% NPK) were evaluated under field conditions during two cropping seasons. In the major season, fruit yield under 5 t ha−1 compost significantly outperformed 50% and 100% NPK and the control. The highest fruit yield (4480 kg ha−1) was obtained under 5 t ha−1 compost in the minor season. While the effect of sole compost was significant on fruit yield, there were also strong trends suggesting added benefits from 2.5 t ha−1 compost+100% NPK. Integrated use of compost and NPK increased shoot biomass over the control and NPK treatments. The compost had significant effect (p < 0.05) on lowering soil pH at the end of study. The highest soil exchangeable Ca and Mg were recorded under sole compost. The findings suggest good prospect for increasing crop yield through inoculating compost with Azotobacter. [ABSTRACT FROM AUTHOR]

Byline: Edeghonghon. Olayemi, Amma. Benneh, Michael. Acquah, Paul. Mensah Patients with neurofibromatosis type 1 (NF1), a common, progressive, autosomal dominant neurocutaneous disorder, are predisposed to malignancies. Several types of hematologic [...]

Elevated instream fine sediment is one of the most important water quality stressors affecting both the structure and function of aquatic ecosystems. This study evaluates whether a predictable pattern of trait distribution of Ephemeroptera, Plecoptera, and Trichoptera (EPT) can be observed along a gradient of sediment stress in eight selected sites in the Tsitsa River and its tributaries. The sites were classified into four site groups according to their fine sediment loads. One‐way analysis of variance was used to test differences in the relative abundance of traits across the site groups. A predictable pattern was observed in 13 of the 27 trait attributes tested, with most traits displaying low abundances in highly disturbed site groups. The relationship between EPT traits and fine sediment stress was analysed using the multivariate RLQ analysis, and the result showed that traits such as swimming, shredding, operculate gill, small body size, and sclerotized body were the dominant traits in the sediment influenced site groups. In the less disturbed site groups, filter feeding, crawling, filamentous gill, soft and exposed body, and large body size were the dominant trait attributes. These observed relationships between EPT traits and sediment stress provide support for the potential usefulness of EPT traits as indicators of fine sediment stress in riverine ecosystems. [ABSTRACT FROM AUTHOR]

Community-based health promotion programmes (CBHPPs) deal with cross cutting issues (social, economic, environmental) and utilise issue-based, population-based and setting-based approaches in programme planning, implementation and evaluation with the aim of empowering individuals and communities to gain control over the determinants of health. This multifaceted nature of CBHPPs has resulted in a number of questions particularly regarding the level of stakeholder involvement in evaluating such programmes. Evaluation is seen as one of the ways to provide evidence to inform health promotion decision-making and practice. Community programme implementers and lay people have lamented that evaluations are often imposed on them without recognition for the uniqueness of their community, its programmes, resources and skills. The aim of this paper is to critically examine the utility of stakeholder involvement in the evaluation of CBHPPs. We first explore the nature of CBHPPs and the methods of gathering evidence via evaluation. This is followed by a critical examination of the value of stakeholder involvement in evaluating CBHPPs. The Ottawa Charter for Health Promotion is used to conceptualise the paper with specific examples of stakeholder involvement in evaluation of CBHPPs used to support our arguments. The paper concludes that stakeholder involvement in evaluation of CBHPPs is of importance considering the empowerment and participation values of health promotion. As evaluation is done with people and not on people, stakeholder involvement should be central to the evaluation of CBHPPs rather than adopting an approach whereby the researcher is completely detached from the programme stakeholders particularly the community. [ABSTRACT FROM AUTHOR]

Abstract: Glyphosate-based herbicides are among the leading products used in South Africa to control weeds and invading alien plant species. Although these herbicides ultimately find their way into aquatic ecosystems, South Africa has no water quality guideline based on indigenous species to protect the country's aquatic biota against these biocides. In this study, South African water quality guidelines (SAWQGs) for Roundup® based on species sensitivity distribution (SSD) using indigenous aquatic biota were developed. Short-term and long-term toxicity tests were conducted with eight different aquatic species belonging to five different taxonomic groups. Static non-renewal experimental methods were employed for short-term lethal tests (≤4 days), and static renewal for long-term sublethal tests (≥4 days ≤21 days). LC50 values for animal exposure and EC50 values for algae were calculated using probit analysis and linear regression of transformed herbicide concentration as natural logarithm data against percentage growth inhibition, respectively. No effect concentration (NEC) was determined based on the dynamic energy budget model, using survival data. The LC50, EC50 and NEC values were used to develop species sensitivity distribution (SSD) concentrations for Roundup®. Based on the SSD concentrations, the short-term and long-term SAWQGs for Roundup® were derived as 0.250 (0.106–0.589) mg/L, and 0.002 (0.000–0.021) mg/L, respectively. These WQGs may be useful in protecting South African aquatic life against transient or long-term exposure to glyphosate-based chemicals as part of integrated water resources management. [Copyright &y& Elsevier]

The article seeks to connect the vibrant debates in the Nordic region on NGOs and the aid system with the international comparative debates on NGOs and development alternatives. It argues for a reformulation of the international debate on NGOs and development alternatives to address the foundational questions related to the formative role and structural impact of the international aid system on NGOs and their roles. This reformulation moves the discussions further and enables analyses that provide understanding of the actual and potential role of NGOs to transform development processes. [ABSTRACT FROM AUTHOR]

This paper sets out an argument for moving forward research on non-governmental organisations (NGOs) within developnment studies. The body of research on NGOs that emerged from the late 1980s onwards focused primarily on NGO roles as development actors and their organisational attributes, but paid less attention to theory and context. While such research had many positive strengths, it was also criticised for its normative focus, and for its vulnerability to changing development fashions and donor preoccupations. Today, attitudes to NGOs have grown more complex and ambiguous, and the institutional landscape in which NGOs are embedded is undergoing rapid change. A new wave of NGO-related research is underway which gives particular emphasis to theory, agency, method and context. Such approaches have the potential to consolidate the field of NGO research within development studies as a more stable and theoretically-grounded subject area. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Surface water is the recipient of pollutants from various sources, including improperly treated wastewater. Comprehensive knowledge of the composition of water is necessary to make it reusable in water-scarce environments. In this work, proton nuclear magnetic resonance (1H-NMR) was combined with multivariate analysis to study the metabolites in four rivers and four wastewater treatment plants releasing treated effluents into the rivers. 1H-NMR chemical shifts of the extracts in CDCl were acquired with Bruker 400. Chemical shifts of 1H-NMR in chlorinated alkanes, amino compounds and fluorinated hydrocarbons were common to samples of wastewater and lower reaches or the rivers. 1H-NMR chemical shifts of carbonyl compounds and alkyl phosphates were restricted to wastewater samples. Chemical shifts of phenolic compounds were associated with treated effluent samples. This study showed that the sources of these metabolites in the rivers were not only from improperly treated effluents but also from runoffs. Multivariate analyses showed that some of the freshwater samples were not of better quality than wastewater and treated effluents. Observations show the need for constant monitoring of rivers and effluent for the safety of the aquatic environment. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor published in the January 2004 issue of the periodical "Family Practice Management" which comments on an article on the joy of family practice.

Achieving sustainable freshwater resource management and conserving biodiversity require accurate and reliable pollution impact assessment. Biomonitoring is an integrative and holistic approach to assessing impact of pollution using biological indicators. In this study, we use the assemblage structure of the freshwater macroinvertebrate family Chironomidae to assess the impact of pollution in a South African river: the Swartkops River. Based on morphological deformities in the mentum of selected genera, we developed a new index, the extended toxic score index (ETSI), to assess the extent of deviation of ecological conditions at the impacted sites from that at the control site. Four sites i.e. Sites 1–4 characterised by different degrees of pollution were selected for chironomids and physico-chemical sampling over a period of three years (August 2009–September 2012). The ETSI was developed by taking into account the severity of deformities, and genera tolerances to pollution. The index was based on the deformities in the mentum of the five most dominant genera: Chironomus , Polypedilum , Tanytarsus , Dicrotendipes and Cricotopus . The values of nutrients, electrical conductivity and turbidity were elevated, and dissolved oxygen depleted at Sites 2, 3 and 4 compared with Site 1. Metal concentrations in the water column were relatively low (<0.3 mg/l). Site 1, i.e. the control site, supported more chironomid species (30 species). Site 2, situated upstream of the Kelvin Jones wastewater effluent discharge point, but influenced by diffuse pollution sources, had more species (22 species) than Sites 3 (10 species) and 4 (18 species). The species assemblage structure clustered largely by sites than by seasons, with the assemblage at Site 1 distinct to those at Sites 2, 3 and 4. The newly developed ETSI was sensitive to pollution, distinguishing between the ecological conditions at the sampling sites. The index placed Site 2 in Category D, indicative of poor ecological condition and Sites 3 and 4 in Category E, indicative of very poor conditions. We found the ETSI to be an appropriate and useful deformity-based tool for biomonitoring, and it can easily be modified and used in other river systems, both locally and internationally. [ABSTRACT FROM AUTHOR]

Glyphosate-based herbicides are among the leading products used in South Africa to control weeds and invading alien plant species. Although these herbicides ultimately find their way into aquatic ecosystems, South Africa has no water quality guideline based on indigenous species to protect the country's aquatic biota against these biocides. In this study, South African water quality guidelines (SAWQGs) for Roundup(®) based on species sensitivity distribution (SSD) using indigenous aquatic biota were developed. Short-term and long-term toxicity tests were conducted with eight different aquatic species belonging to five different taxonomic groups. Static non-renewal experimental methods were employed for short-term lethal tests (≤4 days), and static renewal for long-term sublethal tests (≥4 days ≤21 days). LC50 values for animal exposure and EC50 values for algae were calculated using probit analysis and linear regression of transformed herbicide concentration as natural logarithm data against percentage growth inhibition, respectively. No effect concentration (NEC) was determined based on the dynamic energy budget model, using survival data. The LC50, EC50 and NEC values were used to develop species sensitivity distribution (SSD) concentrations for Roundup(®). Based on the SSD concentrations, the short-term and long-term SAWQGs for Roundup(®) were derived as 0.250 (0.106-0.589) mg/L, and 0.002 (0.000-0.021) mg/L, respectively. These WQGs may be useful in protecting South African aquatic life against transient or long-term exposure to glyphosate-based chemicals as part of integrated water resources management., (Copyright © 2013 Elsevier Inc. All rights reserved.)