Genetic Diversity of Wild Rice (Oryza longistaminata) in Ghana

Oryza longistaminata is a wild rice taxon and an excellent source of genetic variation that remains largely unexploited. This study was conducted to understand the genetic diversity between and within O. longistaminata populations, collected from different geographic locations in Ghana. In this study, SSR markers were used to determine the intra-specific variability in O. longistaminata, and how the variation is partitioned within and between different populations. Analysis of molecular variance revealed high levels of polymorphism (95.9%) within the populations. The overall genetic diversity for all the loci in the six populations was high (Shannon's Information Index I = 0.579, Nei's unbiased expected heterozygosity, He = 0.405). Hierarchical partitioning also indicated a high genetic diversity between and within populations, with some level of relatedness between samples taken from the Savannah agroecological area. The high genetic diversity observed in this study offer a great opportunity for screening useful traits among the populations of O. longistaminata in Ghana for rice breeding programs

Grain quality characteristics of imported rice in Ghana: Implications for breeding for consumer-preferred varieties

ABSTRACTRice is the fastest growing food source in Ghana. The country, however, imports about 70 per cent of its rice requirement due to low volumes of production and poor grain quality of domestic rice compared to imported ones.  In the study, 10 popular imported rice brands on the Ghanaian market were characterised for grain quality traits including grain dimensions, apparent amylose content, gelatinisation temperature, paste viscosity properties, and aroma using physiochemical properties and DNA markers. The rice brands came from Asia and the USA. The rice type from Asia was found to be Jasmine-styled aromatic long grained with low amylose content and gelatinisation temperature, whereas those of USA were conventional long grain with intermediate amylose content and gelatinisation temperature.  These findings were confirmed through DNA marker analyses, with the rice types from Asia and the USA revealing the presence of the TAC and GCC of the waxy gene SNP haplotypes, respectively. The implication for rice breeding in Ghana is discussed.Original scientific paper. Received 29 Oct. 14; revised 03 Aug 15

‘Mining women’ and livelihoods: Examining the dominant and emerging issues in the ASM gendered economic space

Copyright © The Author(s) 2024. The intractable challenges faced by female mine workers have come to dominate the discourse and scholarship on artisanal and small-scale mining (ASM) operations. However, the extensive focus on the informal and labour-intensive segments has engendered a failure to capture the nuances in the duality of ASM operations and how it impacts female outcomes. Drawing on intersectionality as a lens, in this article the authors map the dynamics on how issues related to the gender, situatedness and positionality of female mine workers interact to shape their situated labour outcomes. Highlighting the differentiated outcomes for female mine workers within the contingencies of the broader socio-cultural context in which ASM work is organised, the article sheds light on how the social identity structures such as gender, sexuality and class interact to give form to the marginalisation, occupational roles, the ‘boom town’ narrative and occupational and health challenges that characterise the ASM gendered economic space.The authors received no financial support for the research, authorship, and/or publication of this article

Accommodative anomalies in symptomatic school children in Cape Coast Metropolis, Ghana

Accommodative anomalies even though have been associated with an increased risk of academic failure in the pediatric population, yet have been underappreciated in African populations. This prospective cross sectional study which conformed to the Code of Ethics of the World Medical Association (Declaration of Helsinki) aimed to determine the frequencies of accommodative anomalies among symptomatic Junior High school children in the Cape Coast metropolis, Ghana.Accommodative assessment (testing for amplitude of accommodation, accommodative lag, accommodative facility, and negative and positive relative accommodation) was conducted over best corrected refraction results in a multi-stage sample of 202 symptomatic school children age ranged 12 to 17 years old. Descriptive data was analyzed using frequencies, percentages, means and standard deviations. Binary logistic regression was used to test associations between outcome variables. Of the symptomatic participants (202) assessed, 38 (18.8%) were diagnosed with ametropia, with the most frequent type being astigmatism 19 (9.4%). A number of 104 (51.5 %) symptomatic participants were diagnosed with accommodative anomaly. The frequency of specific accommodative anomalies among symptomatic Junior High school children was as follows: accommodative insufficiency, 45 (22.3%); accommodative infacility, 22(10.9%); accommodative excess, 27(13.4%) and accommodative fatigue, 10 (5%). Participants with accommodative anomalies had greater odds of experiencing symptoms of visual fatigue associated with near work (OR =0.530, p= 0.001) compared with other symptoms. The study results indicate a high prevalence of accommodative anomalies on this symptomatic school going population in Ghana and this can impact negatively on their academic performance.Keywords: Accommodative disorders, ametropia, asthenopic symptom, school children, Ghan

Pesticide exposures in a malarious and predominantly farming area in Central Ghana

In areas where malaria is endemic, pesticides are widely deployed for vector control, which has contributed to reductions in malaria deaths. Pesticide use for agrarian purposes reduces pest populations, thus improving crop production and post-harvest losses. However, adverse health effects have been associated with pesticide exposure, ranging from skin irritation to neurotoxicity and carcinogenicity. Though misuse of these pesticides can lead to widespread potential dangers, the debilitating effects are usually underappreciated in many developing countries. To evaluate the pattern of pesticide usage among rural communities in the Kintampo area of Ghana, a cross-sectional survey was conducted among 1455 heads of households randomly sampled from among 29,073 households in the Kintampo Health and Demographic Surveillance System area of Ghana to estimate the prevalence of pesticide use and indications for use among this rural populace. Seventy-one percent (1040/1455) of household heads reported having used pesticides on either their farms or homes, most commonly for control of weeds (96.4%, 1003/1040) or insects (85.4%, 888/1040). Dichlorodiphenyltrichloroethane (DDT) was used by 22.9% (238/1040) of respondents. The majority of households who reported use of pesticides said women in their households assisted in the spraying efforts (69.3%, 721/1040); of these women, 50.8% (366/721) did so while carrying their babies on their backs. Only 28.9% (301/1040) of the study participants wore protective devices during pesticide applications. Frequent symptoms that were reported after spraying, included cough (32.3%; 336/1040), difficulty in breathing (26.7%; 278/1040) and skin irritation (39.0%; 406/1040). Pesticide use among community members in the Kintampo area of Ghana is common and its potential health impacts warrant further investigation.Key words: Pesticide, malaria, prevalence, Kintampo, dichlorodiphenyltrichloroethane

Genotypic and phenotypic diversity of Mycobacterium tuberculosis complex genotypes prevalent in West Africa

Findings from previous comparative genomics studies of the Mycobacterium tuberculosis complex (MTBC) suggest genomic variation among the genotypes may have phenotypic implications. We investigated the diversity in the phenotypic profiles of the main prevalent MTBC genotypes in West Africa. Thirty-six whole genome sequenced drug susceptible MTBC isolates belonging to lineages 4, 5 and 6 were included in this study. The isolates were phenotypically characterized for urease activity, tween hydrolysis, Thiophen-2-Carboxylic Acid Hydrazide (TCH) susceptibility, nitric oxide production, and growth rate in both liquid (7H9) and solid media (7H11 and Lowenstein-Jensen (L-J)). Lineage 4 isolates showed the highest growth rate in both liquid (p = 0.0003) and on solid (L-J) media supplemented with glycerol (p<0.001) or pyruvate (p = 0.005). L6 isolates optimally utilized pyruvate compared to glycerol (p<0.001), whereas L5 isolates grew similarly on both media (p = 0.05). Lineage 4 isolates showed the lowest average time to positivity (TTP) (p = 0.01; Average TTP: L4 = 15days, L5 = 16.7days, L6 = 29.7days) and the highest logCFU/mL (p = 0.04; average logCFU/mL L4 = 5.9, L5 = 5.0, L6 = 4.4) on 7H11 supplemented with glycerol, but there was no significant difference in growth on 7H11 supplemented with pyruvate (p = 0.23). The highest release of nitrite was recorded for L5 isolates, followed by L4 and L6 isolates. However, the reverse was observed in the urease activity for the lineages. All isolates tested were resistant to TCH except for one L6 isolate. Comparative genomic analyses revealed several mutations that might explain the diverse phenotypic profiles of these isolates. Our findings showed significant phenotypic diversity among the MTBC lineages used for this study

Epitaxial deposition of silver ultra-fine nano-clusters on defect-free surfaces of HOPG-derived few-layer graphene in a UHV multi-chamber by in situ STM, ex situ XPS, and ab initio calculations

The growth of three-dimensional ultra-fine spherical nano-particles of silver on few layers of graphene derived from highly oriented pyrolytic graphite in ultra-high vacuum were characterized using in situ scanning tunneling microscopy (STM) in conjunction with X-ray photoelectron spectroscopy. The energetics of the Ag clusters was determined by DFT simulations. The Ag clusters appeared spherical with size distribution averaging approximately 2 nm in diameter. STM revealed the preferred site for the position of the Ag atom in the C-benzene ring of graphene. Of the three sites, the C-C bridge, the C-hexagon hollow, and the direct top of the C atom, Ag prefers to stay on top of the C atom, contrary to expectation of the hexagon-close packing. Ab initio calculations confirm the lowest potential energy between Ag and the graphene structure to be at the exact site determined from STM imaging

Genomic epidemiological analysis identifies high relapse among individuals with recurring tuberculosis and provides evidence of household recent TB transmission in Ghana

OBJECTIVE: We investigated the cause of recurring tuberculosis (rcTB) among pulmonary TB participants recruited from a prospective population-based study conducted between July 2012 and December 2015. METHODS: Mycobacterium tuberculosis complex isolates obtained from rcTB cases were characterized by standard mycobacterial genotyping tools in addition to whole genome sequencing, followed by phylogenetic analysis to assess strain relatedness. RESULTS: A greater proportion (58.3%, 21/36) of individuals with rcTB episodes had TB recurrence within 12 months post treatment. Only 19.4% (7/36) of participants with rcTB harbored a strain with isoniazid (INH) resistance at baseline of which 29% (2/7) were additionally resistant to rifampicin. However, 27.8% (10/36) harbored an INH resistant strain upon recurring of which 40% (4/10) were MDR-TB strains. Recurrent TB was attributed to relapse (same strain) in 75.0% (27/36) of participants with 25.0% (9/36) attributed to re-infection. CONCLUSION: Our findings indicate that unresolved previous infection due to inadequate treatment may be the major cause of rcTB

Improvement of Rice Production under Drought Conditions in West Africa: Application of QTLs in Breeding for Drought Resistance

Rice plays a paramount role in food and nutrition security in many West African countries. Despite the doubling of production during the last decade, rice consumption has grown faster, creating a deficit between the demand and supply. Although the West African sub-region remains the main rice-producing centre on the continent, production is severely hampered by biotic and abiotic stresses. Drought is one of the factors that most severely reduce grain yields of rice. Systems of production need to be established in order to mitigate yield loss as a result of drought. This review discusses the effects of drought on rice production in West Africa and its mitigation with an emphasis on the improvement of tolerance to drought stress. Yield stability can be achieved by developing drought-tolerant varieties through several processes encompassing profiling of known QTLs and identification of new ones, marker-assisted selection, genomic selection, and extensive multi-locational yield trials. We suggest a comprehensive strategy for breeding drought-tolerant rice varieties in West Africa

Mental Toughness in South African Youth: Relationships With Forgivingness and Attitudes Towards Risk

Young people are particularly vulnerable to health risk behaviors and interpersonal violence, stimulating scholars’ attention towards identifying factors that may reduce the likelihood that these actions will occur. Associated with positive outcomes in a variety of domains, mental toughness in young people might protect them from engaging in potentially deleterious interpersonal or health-risk behaviors, while potentially promoting positive psychological behaviors. Within this framework, the present study investigated the relationships between mental toughness, attitudes towards physical and psychological risk-taking, and trait forgiveness in a sample of 123 (males = 54, females = 69) South African youth (M age = 23.97 years, SD = 4.46). Univariate and multivariate analyses indicated higher levels of mental toughness were associated with being more forgiving, (η2pηp2 = .036), perceiving physical risk-taking more positively (η2pηp2 = .062), but having more negative attitudes towards psychological risk-taking (η2pηp2 = .036). These findings give credence to mental toughness as a psychological characteristic involved in youth risk-taking perceptions and interpersonal functioning. Future research might explore the integration of mental toughness into the development of future youth risk behavior interventions