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1.
A herpetofaunal survey of Muni-Pomadze Lagoon, during the main rainy season (May–June), recorded a total of 32 species (13 amphibians and 19 reptiles). Three species are the first records for coastal habitats in Ghana: Kinixys homeana, Calabaria reinhardti, and Bothrophthalmus lineatus. None of the surveyed species are restricted to Ghana. The most diverse herpetofaunal community occurs in grassland thicket, with 26 species (81% of the sampled herpetofauna). Freshwater ponds include 12 species, while only three species (all amphibians) occur in brackish lagoons. Herpetofaunal conservation efforts at these sites should focus on protecting and monitoring grassland coastal thicket and freshwater ponds. Currently, freshwater pond habitats appear to be stable, but coastal thicket is being lost to provide new agricultural land at Muni. Hyperolius reedfrogs, pythons (Python regius) and monitor lizards (Varanus exanthematicus and V. niloticus) appear to offer the greatest potential for undertaking long-term monitoring of the coastal lagoon herpetofauna, because they can be more readily surveyed, and are likely to be sensitive to a broad range of environmental stressors.  相似文献   

2.
Objectives: While colorectal cancer (CRC) is common, its incidence significantly varies around the globe. The incidence of CRC in West Africa is relatively low, but it has a distinctive clinical pattern and its molecular characteristics have not been studied. This study is one of the first attempts to analyze molecular, genetic, and pathological characteristics of colorectal cancer in Ghana. Methods: DNA was extracted from microdissected tumor and adjacent normal tissue of 90 paraffin blocks of CRC cases (1997–2007) collected at the University of Ghana. Microsatellite instability (MSI) was determined using fragment analysis of ten microsatellite markers. We analyzed expression of mismatch repair (MMR) proteins by immunohistochemistry and sequenced exons 2 and 3 of KRAS and exon 15 of BRAF. Results: MSI analysis showed 41% (29/70) MSI-High, 20% (14/70) MSI-Low, and 39% (27/70) microsatellite-stable (MSS) tumors. Sequencing of KRAS exons 2 and 3 identified activating mutations in 32% (24/75) of tumors, and sequencing of BRAF exon 15, the location of the common activating mutation (V600), did not show mutations at codons 599 and 600 in 88 tumors. Conclusions: Our study found a high frequency of MSI-High colorectal tumors (41%) in Ghana. While the frequency of KRAS mutations is comparable with other populations, absence of BRAF mutations is intriguing and would require further analysis of the molecular epidemiology of CRC in West Africa.  相似文献   

3.
In this paper I examine the complexity of human forces involved in tree cutting in a Ghanaian forest region. I provide evidence to link the indiscriminate tree-cutting activities of some local communities to the gradual loss of communal control over land and the replacement of kin group control with state property regimes. I point to the interrelated factors of the state's promotion of an exportled development strategy, the intensification of agricultural commercialization, and household and group variations in access to land as all having deleterious impacts on local traditions of sustainable forestry.  相似文献   

4.
5.
The pollination of Ficus vogelii in Ghana   总被引:1,自引:0,他引:1  
Ficus vogelii is a primitive monoecious species, in which staminate and pistillate flowers are distributed throughout the syconium without localization. There is no bimodal structural distinction between seed flowers and gall flowers, and any pistillate flower is capable of seed production. Each syconium follows a development cycle lasting approximately 45 days. The chief pollen vector is the agaonid wasp Allotriozoon heterandromorphum , which is an obligate symbiont. Adult females of this species have mesothoracic "pockets" in which pollen is carried. Adult males do not display the anther-cutting activity reported in other species. The life cycle of the pollinator is described in relation to the developmental cycle of the syconium.  相似文献   

6.
Total concentrations of Hg, Al, Fe, As, Pb, Cu, Cr, Ni, Mn, Co, V, and Zn were determined in surface sediments collected from 21 locations within the gold mining impacted Pra River basin in southwestern Ghana. Samples were collected during both the rainy and dry seasons. We hypothesized that in the rural southwestern portion of Ghana, the lack of industrial activities makes artisanal gold mining (AGM) by Hg amalgamation the main source of water resource contamination with heavy metals. Therefore, metals showing concentration trends similar to that of Hg in the studied system are likely impacted by AGM. We found that total-Hg (THg) concentrations in riverine sediments are rather low as compared to other aquatic systems that are impacted by similar mining activities. Measured THg concentrations ranged from 0.018 to 2.917 mg/kg in samples collected in the rainy season and from about 0.01 to 0.043 mg/kg in those collected during the dry season. However, the determination of the enrichment factor (EF) calculated using shale data as reference background values showed signs of severe contamination in most of the sampled sites. In the dry season, THg concentrations correlated positively and significantly to the concentrations of As (r = 0.864, p < 0.01), Cu (r = 0.691, p < 0.05), and Ni (r = 0.579, p < 0.05). Based on our previously stated hypothesis, this could then be an indication of the impact of AGM on ambient levels of these 3 elements. However, the determined concentrations of Cu, and Ni co-varied significantly with Al, suggesting that natural sources do account for the observed levels. Accordingly, both AGM and metal inputs from weathered natural deposits are likely co-responsible for the observed levels of Cu and Ni. In contrast, the lack of correlation between As and Al tends to suggest an impact of AGM on As levels. Overall, our data suggest that besides Hg and to some extent As, the impact of AGM on ambient levels of investigated metals in the gold mining impacted Pra River remains negligible. Finally, the increase in metal concentrations from the dry to the rainy season underlines the impact of changes in hydrologic conditions on levels and fate of metals in this tropical aquatic system.  相似文献   

7.
The emergence of the gold mining industry and the influx of artisanal and small-scale mining following recent discoveries of gold deposits in Northern Ghana have posed new socio-cultural, economic, environment and health challenges for residents in this dry savannah zone that is already facing negative consequences of environmental change. Yet, the extent to which residents in close proximity (impacted) and distant (affected) host communities perceive the impact of mining on their health has been nascent. Using cross sectional survey data (n=801) and applying the negative log-log regression technique, we examine residents’ self-rated health in mining communities in the Upper West Region of Ghana. The findings suggest that residents in impacted communities who believed that odors from mining activities could have health impact were twice more likely to report their health as poor, while those who were uncertain were 98% more likely to rate their health poor compared to those who disbelieved. However, sighting of dust was not significantly associated with subjective health in both impacted and affected communities. Based on these findings, it is recommended that Ghana's Minerals and Mining Act be reviewed to include the active involvement of host communities in mine leases while enforcing strict environmental best practices.  相似文献   

8.
Carola Lentz 《Ethnos》2013,78(1):107-136
The article discusses the colonial construction of ethnic categories, their linkage with precolonial models of identity and the multiple meanings which ethnicity has assumed for different groups over the past decades, using the example of northwestern Ghana – a region which, in the precolonial period, was neither politically centralized nor knew distinct ‘tribes’. The article analyses how ethnic categories, boundaries and institutions were created and continually redefined by colonial officials, anthropologists, chiefs, labour migrants and educated elites, and how the different ethnic discourses fed into each other. It also draws on some of the older literature on ethnicity in Africa because it can still contribute to our understanding of the making of ethnic identities when framed in a deeply historical approach.  相似文献   

9.
10.
Even though Sfax salina in Tunisia hosts a significant part of the Mediterranean population of Pied Avocet Recurvirostra avosetta, data on the breeding ecology of this species in this area are lacking. Such data are nonetheless necessary, not only for the understanding of the ecology and dynamics of this species in general, but also for conservation purposes. In this paper we use the results of a one-year monitoring of nests in Sfax salina to provide information on its nesting parameters, in particular nesting phenology, colony size and hatching success. Our results show that Pied Avocets formed dense colonies at the beginning of the nesting season, but colony size decreased as the nesting season advanced. Clutch size varied between 1 and 7 eggs, similar to other Mediterranean and European populations. Hatching success, estimated by the Mayfield method, was relatively low, mainly due to predation by stray dogs. Overall, our work shows that relatively high nest losses occur here. It also highlights the need for management efforts aiming to enhance the reproductive success in this artificial habitat. Creation of suitable and safe nesting sites is proposed.  相似文献   

11.
Medical physics has been an indispensable and strategic stakeholder in the delivery of radiological services to the healthcare system of Ghana. The practice has immensely supported radiation oncology and medical imaging facilities over the years, while the locally established training programme continues to produce human resource to feed these facilities. The training programme has grown to receive students from other African countries in addition to local students. Ghana has been recognised by the International Atomic Energy Agency as Regional Designated Centre for Academic Training of Medical Physicists in Africa. The Ghana Society for Medical Physics collaborates with the School of Nuclear and Allied Sciences of the University of Ghana to ensure that training offered to medical physicists meet international standards, making them clinically qualified. The Society has also worked together with other bodies for the passage of the Health Profession’s Regulatory Bodies Act, giving legal backing to the practice of medical physics and other allied health professions in Ghana. The country has participated in a number of International Atomic Energy Agency’s projects on medical physics and has benefited from its training courses, fellowships and workshops, as well as those of other agencies such as International Organization for Medical Physics. This has placed Ghana’s medical physicists in good position to practice competently and improve healthcare.  相似文献   

12.
近些年来,我国十分重视医学生职业道德教育,然而,在医德教学实践中仍存在着观念落后、内容失衡和方法单一等多方面问题。同时,随着我国多元结构社会的形成,医学生的思想状况和价值观趋于复杂化,从业时职业道德水平出现滑坡。针对目前医学生医德教育存在的种种问题,试图从加强和改进医学生医德教育的角度,探索医学生医德教育改革,增强医学生医德教育的实效性。  相似文献   

13.
Occurrences of panic attacks associated with belief in genital retraction have been described in the anthropological and psychological literature in terms of culture bound reactive syndromes. Similar phenomena occur widely in West Africa, where they are reported as cases of penis snatching. Explanations for these phenomena range from the biomedical emphasis on pathology to the social psychological emphasis on altered perceptual sets. This paper provides a narrative of an accusation of genital theft in a rural West African settlement. Drawing from ethnographic information, it will be argued that the case is best explained in light of social relations, definitions for in-groups and out-groups, and local knowledge concerning witchcraft and divination. Local explanations for the case conform to both biomedical and social psychological models.  相似文献   

14.
ABSTRACT

An account is presented of the chemistry and algal flora of two streams in Ekiti State, Nigeria. The two streams, one of which is much warmer than the other, are separate upstream but subsequently merge. A comparison of the springs revealed that while they differed markedly in temperature, colour, turbidity, conductivity, solids, total alkalinity, total hardness, Ca, SiO3, SO4, Mg, Cl- and dissolved oxygen, they showed some similarities in pH, Fe, Na, K, PO4 and NO3. In the cold spring, while total alkalinity, conductivity and silicate increased in the wet season, total hardness decreased slightly and other variables exhibited fluctuations with season. For the warm spring, except for increased total alkalinity and total hardness, dissolved oxygen and pH decreased in the wet season. However, most parameters of the warm spring were unaffected by season. Floristically, the springs were rich in species with a total of 84 taxa: 56 in the warm spring, 33 in the cold spring, 44 at the confluence and 40 beyond the confluence. The warm spring was dominated mainly by blue-green algae such as Lyngbya birgei, Synechococcus aequalis and Oscillatoria spp.; the cold spring was dominated by Rhizoclonium hieroglyphicum and Navicula spp. The confluence was dominated by Terpsinoe musica, R. hieroglyphicum and Lyngbya birgei, while the site downstream of the confluence was dominated entirely by R. hieroglyphicum. In most cases, the confluence and downstream area beyond the confluence of the springs exhibited intermediate characteristics between the two springs. This study is a contribution to the dearth of information on streams in West Africa.  相似文献   

15.
The family Ariidae, sea catfish of the order Siluriformes, is widely distributed throughout the world, particularly in tropical and subtropical areas. The three species of Ariidae found on the coasts and estuaries of West Africa are the smoothmouth catfish Carlarius heudelotii (Valenciennes 1840), the rough-head catfish Carlarius latiscutatus (Günther 1864) and the Guinean sea catfish Carlarius parkii (Günther 1864). They have been increasingly exploited by artisanal and industrial coastal fisheries in recent decades, but there is still little information available on their ecology and biology. The aim of this study was to deepen our knowledge of these three West African Ariidae species based on a dataset collected between 1980 and 2013 during experimental fishing programmes. They were carried out in Mauritania in the Banc d'Arguin National Park, in Senegal in the Sine Saloum estuary including the Bamboung Marine Protected Area (MPA), in The Gambia in the Gambia estuary, in Guinea-Bissau in the Urok Islands MPA in the Bijagos archipelago, in Guinea in the Fatala estuary and Dangara inlet, and in Côte d'Ivoire in the Ebrié Lagoon. C. latiscutatus accounted for 65%, C. parkii for 29% and C. heudelotii for 6% of total number of Ariidae sampled. C. latiscutatus was abundant in the Sine Saloum and Gambia estuaries as well as in Guinea and Guinea-Bissau and was the only species present in the Ebrié Lagoon. C. parkii was in the majority in Mauritania. The three species were recorded in a salinity range of 0 to 50, a temperature range of 19 to 34°C, in areas 1.7 to 15 m depth, and transparency ranging from 0.1 to 4 m (Secchi disk depth). C. heudelotii was present in less saline (25 vs. 32–34), less warm (27 vs. 29°C) and less transparent (0.8 m vs. 1.6 m) waters than the two other species. The maximum sizes (453 mm, 614 mm and 525 mm for, respectively, C. heudelotii, C. latiscutatus and C. parkii) were comparable to those recorded at sea. Length–weight relationships calculated for each species showed b coefficients greater than 3. Sex ratios were always in favour of females. The number of mature individuals and their smallest size at maturity were calculated per species, sex and study area. A size of 27–28 cm at first maturity was estimated for females of C. latiscutatus. A few dozen records made it possible to describe fecundity and cases of oral incubation by females. The diet of the three species was composed of crustaceans, fish and molluscs, confirming their classification as generalist predators. Thanks to their high environmental tolerance, these sea catfish populations are able to occupy both the continental shelf and adjacent estuaries throughout their life cycle, with the exception of spawning, which generally takes place at sea.  相似文献   

16.
Khan  M. A.  Kamuru  F. 《Hydrobiologia》1997,354(1-3):151-156
Seasonal studies were undertaken (August 1983–July 1984) toevaluate the algal distribution and ecology of the RiverDelimi, Jos Plateau, Nigeria at three stations: upstream, withlittle allochthonous input; midstream, receiving heavy domesticaffluents; downstream. A wide amplitude of variability wasdiscernible in physicochemical factors, and photosyntheticactivity and abundance of suspended algae in relation to thedegree of pollution along the first 7-km stretch of the river.Conductivity (µS cm-1) showed a 9-fold increase fromupstream (x = 35) to downstream. The standing crop(Chl a) fluctuated markedly, with 6-times higher valuesfor a polluted midstream site (x = 18.2 mg m-3). Production rate measurements (mg C m-3 d-1) showed significant variability with relatively lowvalues (x = 610) recorded for the upstream andhighest (x = 1050) at the midstream site. Apositive correlation was obtained between production rates andChl a for the polluted midstream zone.  相似文献   

17.
According to the World Health Organization (WHO) cardiovascular disease (CVD) is the leading cause of death globally. Over 80% of CVD deaths take place in low‐ and middle‐income countries (LMICs). It is estimated that 1 million to 2 million people worldwide die each year due to lack of access to an implantable cardiac defibrillator (ICD) or a pacemaker. Despite the medical, legal, cultural and ethical controversies surrounding the pacemaker reutilization, studies done so far on the reuse of postmortem pacemakers show it to be safe and effective with an infection rate of 1.97% and device malfunction rate of 0.68%. Pacemaker reutilization can be effectively and safely done and does not pose significant additional risk to the recipient. Heart patients with reused pacemakers have an improved quality of life compared to those without pacemakers. The thesis of this paper is that pacemaker reutilization is a life‐saving initiative in LMICs of Nigeria and Ghana. It is cost effective; consistent with the principles of beneficence, nonmaleficence, and justice with a commitment to stewardship of resources and the Common Good. Used pacemakers with adequate battery life can be properly sterilized for use by patients in LMICs who cannot afford the cost of a new pacemaker.  相似文献   

18.
We evaluated the impacts of anthropogenic disturbance on community structure and diversity along three management zones of the Bia biosphere reserve in Ghana. Sixty sample plots were distributed among the core, buffer and transition zones. We estimated the degree of disturbances from discernible indicators on the field and satellite images. All tree species ≥10 cm dbh (diameter at breast height) were identified and enumerated. Inventory data were compared across the zones and related to intensity of disturbances. A total of 1176 individual trees from 108 species and 33 families were encountered. Number of species varied from 27 in the highly disturbed (HD) to 61 in the least disturbed (LD) zone. Mean basal area (BA) varied from 11.71 in the HD to 28.26 in the LD. Both Margalef's species richness and Shannon‐Weiner's α‐diversity were highest in the moderately disturbed (MD) than either the least and most disturbed zones. Our study revealed significant differences in tree abundance, stem density, BA and species diversity, attributable to differences in degree of anthropogenic disturbances among zones. Given the different levels of anthropogenic disturbance and corresponding impacts across the reserve, we recommend an integrated management strategy for the conservation of biodiversity in the Bia biosphere reserve.  相似文献   

19.
Climatic changes have profound effects on the distribution of biodiversity, but untangling the links between climatic change and ecosystem functioning is challenging, particularly in high diversity systems such as tropical forests. Tropical forests may also show different responses to a changing climate, with baseline climatic conditions potentially inducing differences in the strength and timing of responses to droughts. Trait‐based approaches provide an opportunity to link functional composition, ecosystem function and environmental changes. We demonstrate the power of such approaches by presenting a novel analysis of long‐term responses of different tropical forest to climatic changes along a rainfall gradient. We explore how key ecosystem's biogeochemical properties have shifted over time as a consequence of multi‐decadal drying. Notably, we find that drier tropical forests have increased their deciduous species abundance and generally changed more functionally than forests growing in wetter conditions, suggesting an enhanced ability to adapt ecologically to a drying environment.  相似文献   

20.
Ghana, a developing country in West Africa, has major medical burdens in taking care of a large population with limited resources. Its three medical schools produce more than 200 graduates per year, but most emigrate to developed lands after training. Ghana is working to educate and retain locally trained physicians, but it is difficult to get them to work in rural settings where the need is greatest. This article details the establishment of a General Medicine residency at a 150-bed hospital in rural Ghana. Early training comprises 6 months each in Medicine, Surgery, OB/GYN, and Pediatrics; the hospital in Techiman also has a Surgery residency. House officers choose the program for more hands-on experience than they can get in larger centers. They perform many tasks, including surgery, sooner and more independently than do residents in developed countries. The training program includes a morning report, clinical teaching rounds, and rotations on in-patient wards and in the Emergency Department and clinics. Teaching focuses on history, physical examination, good communication, and proper follow-up, with rigorous training in the OR and some clinical research projects pertinent to Ghana. Trainees work hard and learn from one another, from a dedicated faculty, and by evaluating and treating very sick patients. Ghana’s rural residencies offer rigorous and attractive training, but it is too soon to tell whether this will help stem the “brain drain” of young physicians out of West Africa.  相似文献   

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