44 research outputs found
A Survey of the Benthic Macrofauna and Fish Species Assemblages in a Mangrove Habitat in Ghana
In order to enhance ecological knowledge for coastal and mangrove ecosystem conservation in Ghana, the study documents the taxonomic groups of benthic macrofauna and fish assemblages in an urban mangrove swamp as its fundamental objective with emphasis on their composition, richness and diversity. This is because benthic and fish fauna of mangrove habitats are amongst the least studied biota in Ghana. Fish and benthos sampling was undertaken from five randomly selected pools within a mangrove stand during the wet and dry seasons using pole-seine net (7 m long and 1.5 m depth, with stretched mesh size of 5 mm) and an Ekman grab (15 cm × 15 cm dimensions), respectively. All samples were preserved in 10% formalin for laboratory analysis. The results indicated a more diverse macrozoobenthic community in the wet (H¹ = 1.8) than dry season (H¹ = 1.5) . Overall, five out of a total of 13 genera found are intolerant to pollution and four moderately tolerant, while four comprising polychaetes and the midge Chironomus, are pollution tolerant. This suggests that the mangrove habitat is less polluted. A grand total of 917 fish specimens, belonging to 15 species and nine families, were encountered for both seasons (371 and 546 specimens for wet and dry seasons, respectively). The black-chinned tilapia, Sarotherodon melanotheron, was the dominant fish species in the wet season, accounting for 54.2% of the total fish caught, whilst the grey mullets, Mugil babanensis and Mugil curema, were the dominant species in the dry season, with a combined total of 51.4% of the fish population. However, over 70% of these dominant fish species from both seasons were juveniles providing a strong justification for the observation that the mangrove habitats are nursery grounds for fish inhabiting adjacent riverine, estuarine and inshore marine habitats. Considering this relevance of mangroves and the ongoing conversion attempts of mangrove habitats to other land uses, a concerted mangroves conservation effort is strongly advocated
Self-reported drunkenness among adolescents in four sub-Saharan African countries: associations with adverse childhood experiences
<p>Abstract</p> <p>Background</p> <p>Consumption of alcohol is associated with acute and chronic adverse health outcomes. There is a paucity of studies that explore the determinants of alcohol use among adolescents in sub-Saharan Africa and, in particular, that examine the effects of adverse childhood experiences on alcohol use.</p> <p>Methods</p> <p>The paper draws on nationally-representative data from 9,819 adolescents aged 12-19 years from Burkina Faso, Ghana, Malawi, and Uganda. Logistic regression models were employed to identify correlates of self-reported past-year drunkenness. Exposure to four adverse childhood experiences comprised the primary independent variables: living in a food-insecure household, living with a problem drinker, having been physically abused, and having been coerced into having sex. We controlled for age, religiosity, current schooling status, the household head's sex, living arrangements, place of residence, marital status, and country of survey. All analyses were conducted separately for males and females.</p> <p>Results</p> <p>At the bivariate level, all independent variables (except for coerced sex among males) were associated with the outcome variable. Overall, 9% of adolescents reported that they had been drunk in the 12 months preceding the survey. In general, respondents who had experienced an adverse event during childhood were more likely to report drunkenness. In the multivariate analysis, only two adverse childhood events emerged as significant predictors of self-reported past-year drunkenness among males: living in a household with a problem drinker before age 10, and being physically abused before age 10. For females, exposure to family-alcoholism, experience of physical abuse, and coerced sex increased the likelihood of reporting drunkenness in the last 12 months. The association between adverse events and reported drunkenness was more pronounced for females. For both males and females there was a graded relationship between the number of adverse events experienced and the proportion reporting drunkenness.</p> <p>Conclusions</p> <p>We find an association between experience of adverse childhood events and drunkenness among adolescents in four sub-Saharan African countries. The complex impacts of adverse childhood experiences on young people's development and behavior may have an important bearing on the effectiveness of interventions geared at reducing alcohol dependence among the youth.</p
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Pooled analysis of WHO Surgical Safety Checklist use and mortality after emergency laparotomy
Background The World Health Organization (WHO) Surgical Safety Checklist has fostered safe practice for 10 years, yet its place in emergency surgery has not been assessed on a global scale. The aim of this study was to evaluate reported checklist use in emergency settings and examine the relationship with perioperative mortality in patients who had emergency laparotomy. Methods In two multinational cohort studies, adults undergoing emergency laparotomy were compared with those having elective gastrointestinal surgery. Relationships between reported checklist use and mortality were determined using multivariable logistic regression and bootstrapped simulation. Results Of 12 296 patients included from 76 countries, 4843 underwent emergency laparotomy. After adjusting for patient and disease factors, checklist use before emergency laparotomy was more common in countries with a high Human Development Index (HDI) (2455 of 2741, 89.6 per cent) compared with that in countries with a middle (753 of 1242, 60.6 per cent; odds ratio (OR) 0.17, 95 per cent c.i. 0.14 to 0.21, P <0001) or low (363 of 860, 422 per cent; OR 008, 007 to 010, P <0.001) HDI. Checklist use was less common in elective surgery than for emergency laparotomy in high-HDI countries (risk difference -94 (95 per cent c.i. -11.9 to -6.9) per cent; P <0001), but the relationship was reversed in low-HDI countries (+121 (+7.0 to +173) per cent; P <0001). In multivariable models, checklist use was associated with a lower 30-day perioperative mortality (OR 0.60, 0.50 to 073; P <0.001). The greatest absolute benefit was seen for emergency surgery in low- and middle-HDI countries. Conclusion Checklist use in emergency laparotomy was associated with a significantly lower perioperative mortality rate. Checklist use in low-HDI countries was half that in high-HDI countries.Peer reviewe
Tidal influence on fish faunal occurrence and distribution in an estuarine mangrove system in Ghana
This study assessed the effects of tidal stages and habitat conditions on nekton assemblage and distribution in the Kakum River estuarine mangrove system in the Central Region of Ghana. Teleosts and crustaceans were sampled using pole seine and cast net from a tidal mangrove pond and a channel, and characterised using morphometry and ecological guilds concept. In total, 1 146 specimens were collected, with 35 species from 19 families represented. The most abundant species encountered were Liza spp. (Mugilidae; 36%), Sarotherodon melanotheron (Cichlidae; 16%), Elops lacerta (Elopidae; 6%) and Sardinella aurita (Clupeidae; 5%), which exhibited pronounced spatial distribution. Sarotherodon melanotheron showed preference for ponds with minimal water flow and depth, Sardinella aurita occurred only in deeper sections of the mangrove channel with significant flow velocity, and Elops lacerta in the pond and all channel stations. Mugilids were found exclusively in the channel, whereas Palaemonidae (Macrobrachium macrobrachion and M. vollenhoveni) occurred in specific locations in the channel, with speciesspecific preferences for tidal stages. Most species encountered were identified to be predominantly marine migrants with bentophagous feeding habit. Site selection and tidal stages were found to affect the occurrence and distribution of fishes over a tidal cycle and interactively influence species diversity
Responses of stomates of talinum triangulare and tradescantia virginiana to some growth regulators
No Abstract. Journal of the Ghana Association Vol. 2 (3) 1999: pp.137-14
Socioeconomic dynamics of the Ghanaian tuna industry: a value-chain approach to understanding aspects of global fisheries
This study investigated how an industrial tuna fishery functions in terms of procedures, practices, governance and finance in the context of Ghana, West Africa. Tuna is Ghana’s biggest seafood export, contributing significantly to the domestic fisheries sector. A case-study approach was used to analyse relevant social and economic factors at the local scale to better understand how the global seafood industry operates in a low-income country. A value-chain framework was adopted to assess market structures, sales pathways and revenue distribution. We also investigated the role of actors engaged in the industry using secondary data, interviews, questionnaires and participant observations. The results revealed a changing organisational structure in tuna production, moving from bait-boat fishing with smaller companies to large-scale purse-seine fishing backed by consolidated Asian seafood companies. Production was found to depend significantly on local female intermediaries for access to funds through prefinancing arrangements. Considerable illegalities were identified within the value chain, highlighting the need for improved partnership and licensing negotiations, and for low-cost marine control and surveillance tools. As vertical integration increases within the industry, the influence of corporations as keystone actors becomes evident for the future social and ecological sustainability of the industry.Keywords: gender, global markets, industrial fishery, international seafood trade, IUU fishing, keystone actors, West Afric
Regulatory effects of cultar and iat siol treat on soybean (Glycine max (L) Merr.)
No Abstract. Journal of the Ghana Science Association Vol. 2 (2) 1999: pp.15-2
Psyllium: a promising polymer for sustained release formulations in combination with HPMC polymers
Psyllium has a mucilaginous property that makes it a good candidate to be utilized as an
excipient in the preparation of controlled release systems. Various formulations were prepared
using theophylline as a model drug and investigated with a view to achieve an ideal slow drug
release profile. The addition of hydroxypropyl methylcellulose (HPMC) to psyllium significantly
reduced the burst release; however, the percentage of drug release within a 12 h period was
too slow and thereby inadequate. This was overcome by the addition of lactose as a hydrophilic
filler that enabled a slow release with roughly 80% drug release in 12 h. The inclusion of HPMC
within psyllium formulations changed the drug release kinetics from Fickian diffusion to
anomalous transport. Granulated formulations demonstrated slower drug release than
ungranulated or physical mixture and caused a change in the dissolution kinetics from
Fickian diffusion to anomalous transport. Milled granules showed more efficient controlled
drug release with no burst release. Milling of the granules also changed the drug release
kinetics to anomalous transport. Although psyllium was proved to be a promising polymer to
control the drug release, a combination of psyllium-HPMC and formulation processes should be
considered in an attempt to achieve a zero-order release