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1.
Currently 70% of the population in Cameroon are reliant on solid fuel for cooking (90% in rural communities) and the associated household air pollution contributes to significant mortality and morbidity in the country. To address the problems of energy security, deforestation and pollution the government has developed a strategy (Masterplan) to increase use of liquified petroleum gas (LPG) as a cooking fuel from 12% to 58% by 2030. As a clean fuel scaled adoption of LPG has the potential to make significant positive impacts on population health. The LPG Adoption in Cameroon Evaluation (LACE) studies are assessing in the community (i) barriers and enablers for and (ii) local interventions to support, adoption and sustained use of LPG. A census survey conducted for LACE in rural and peri-urban regions of SW Cameroon provided an opportunity to investigate current fuel use patterns and factors associated with primary and exclusive use of LPG. A cross-sectional survey of 1577 households (1334 peri-urban and 243 rural) was conducted in March 2016 using standardised fuel use and household socio-demographic questions, administered by trained fieldworkers. Wood (40.7%) and LPG (51.1%) were the most frequently reported fuels, although the dominant fuels in rural and peri-urban communities were wood (81%) and LPG (58%) respectively. Fuel stacking was observed for the majority of LPG using households (91% of peri-urban and 99% of rural households). In rural homes, a higher level of education, access to sanitation and piped water and household wealth (income and asset ownership) were all significantly associated with LPG use (p < 0.05). In peri-urban homes, younger age, access to sanitation and piped water and increasing education were significantly associated with both any and exclusive use of LPG (p < 0.05). However, whilst household wealth was related to any LPG use, there was no relationship with exclusive use. Results from this census survey of a relatively well-established LPG market with lower levels of poverty and high levels of education than Cameroon as a whole, find LPG usage well below target levels set by the Cameroon government (58% by 2030). Fuel stacking is an issue for the majority of LPG using households. Whilst, as observed here, education, household wealth and socio-economic status are well recognised predictors of adoption and sustained use of clean modern fuels, it is important to consider factors across the whole LPG eco-system when developing policies to support their scaled expansion. A comprehensive approach is therefore required to ensure implementation of the Cameroon LPG Masterplan achieves its aspirational adoption target within its stated timeframe.  相似文献   

2.
Like many other countries, Ghana relies on biomass (mainly wood and charcoal) for most of its cooking needs. A national action plan aims to expand liquefied petroleum gas (LPG) access to 50% of the country’s population by 2020. While the country’s southern urban areas have made progress toward this goal, LPG use for cooking remains low in the north. The aim of this cross-sectional study was to characterize the current state of the LPG market in this area and examine opportunities and barriers to scale up LPG adoption. We interviewed 16 LPG suppliers (stove, cylinder, and fuel vendors) as well as 592 households in the Kassena-Nankana Districts (KND) of Ghana. We find large rural–urban differences in LPG uptake: less than 10% of rural households own LPG stoves compared with over half of urban households. Awareness of LPG is high across the region, but accessibility of fuel supply is highly limited, with just one refilling station located in the KND. Affordability is perceived as the main barrier to LPG adoption, and acceptability is also limited by widespread concerns about the safety of cooking with LPG. Transitioning to a cylinder recirculation model, and providing more targeted subsidies and credit options, should be explored to expand access to cleaner cooking in this region.  相似文献   

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To guide control policies, it is important that the determinants of influenza transmission are fully characterized. Such assessment is complex because the risk of influenza infection is multifaceted and depends both on immunity acquired naturally or via vaccination and on the individual level of exposure to influenza in the community or in the household. Here, we analyse a large household cohort study conducted in 2007–2010 in Vietnam using innovative statistical methods to ascertain in an integrative framework the relative contribution of variables that influence the transmission of seasonal (H1N1, H3N2, B) and pandemic H1N1pdm09 influenza. Influenza infection was diagnosed by haemagglutination-inhibition (HI) antibody assay of paired serum samples. We used a Bayesian data augmentation Markov chain Monte Carlo strategy based on digraphs to reconstruct unobserved chains of transmission in households and estimate transmission parameters. The probability of transmission from an infected individual to another household member was 8% (95% CI, 6%, 10%) on average, and varied with pre-season titers, age and household size. Within households of size 3, the probability of transmission from an infected member to a child with low pre-season HI antibody titers was 27% (95% CI 21%–35%). High pre-season HI titers were protective against infection, with a reduction in the hazard of infection of 59% (95% CI, 44%–71%) and 87% (95% CI, 70%–96%) for intermediate (1∶20–1∶40) and high (≥1∶80) HI titers, respectively. Even after correcting for pre-season HI titers, adults had half the infection risk of children. Twenty six percent (95% CI: 21%, 30%) of infections may be attributed to household transmission. Our results highlight the importance of integrated analysis by influenza sub-type, age and pre-season HI titers in order to infer influenza transmission risks in and outside of the household.  相似文献   

4.
Standard life cycle assessment (LCA) methodology has been used to determine and compare the environmental impacts of three different cooking fuels used in Ghana, namely, charcoal, biogas, and liquefied petroleum gas (LPG). A national policy on the use of cooking fuels would have to look at the environmental, social, and cost implications associated with the fuel types. This study looked at the environmental aspect of using these fuels. The results showed that global warming and human toxicity were the most significant overall environmental impacts associated with them, and charcoal and LPG, respectively, made the largest contribution to these impact categories. LPG, however, gave relatively higher impacts in three other categories of lesser significance—that is, eutrophication, freshwater aquatic ecotoxicity, and terrestrial ecotoxicity potentials. Direct comparison of the results showed that biogas had the lowest impact in five out of the seven categories investigated. Charcoal and LPG had only one lowest score each. From the global warming point of view, however, LPG had a slight overall advantage over the others, and it was also the most favorable at the cooking stage, in terms of its effect on humans.  相似文献   

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Missoup, A.D., Nicolas, V., Wendelen, W., Keming, E., Bilong Bilong, C.F., Couloux, A., Atanga, E., Hutterer, R. & Denys, C. (2012). Systematics and diversification of Praomys species (Rodentia: Muridae) endemic to the Cameroon Volcanic Line (West Central Africa). —Zoologica Scripta, 41, 327–345. Our integrative approach combines two mitochondrial genes (16S and cyt b gene), two nuclear genes (exon 10 GHR and exon 1 IRBP) and craniometrical data to test the status and to infer phylogenetic relationships of the three Praomys Cameroon Volcanic Line endemics (P. hartwigi, P. morio and P. obscurus). The taxonomic rank of the principal genus group is assessed and the mode of diversification of species of the P. tullbergi complex in Afrotropical forests is discussed based on estimates of times to the most recent common ancestors and on tree topologies. This study documents for the first time the molecular and morphometrical distinctiveness of P. hartwigi and P. morio within the P. tullbergi species complex. Further studies including specimens of P. hartwigi from all its distribution range are needed to conclude on the status of P. obscurus. The monophyly of the genus Praomys is refuted. Times to the most recent common ancestors of major clades within the P. tullbergi species complex are estimated for the last 2.5 Mya and during the last 1 or 2 Mya for different species or forms. The lowland forest refuge hypothesis might well explain the diversification of P. misonnei, P. rostratus and P. tullbergi in the guineo‐congolese forest block. The isolation of montane forests could have facilitated the divergence between the two montane forest forms P. hartwigi and P. obscurus and between populations of P. morio from the continent and those from the island of Bioko. Praomys populations (species) that inhabit the Cameroon Volcanic Line Praomys probably originated as lowland forms subsequently specialized to highland conditions.  相似文献   

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This paper considers the altitudinal zonation ofFicus on the southern slopes of the Bamboutos Mountains, Cameroon, and attempts to understand how these species have been appropriated by the Bamileke people. Five commonly used species ofFicus are propagated using pole cuttings. This genus contains important species in the farming system which have specific growth and development requirements. They mark the land ownership boundaries, as symbolic trees which give shelter to the lineage gods, and as important parts offence structure. They are incorporated into and contribute to the management of the territory. The landscape is criss-crossed with hedges which allow the integration of cropping and breeding activities. Their rapid growth also constitutes an important source of firewood and cuttings. The Bamileke’s long use of and interest in theFicus genus is demonstrated by the variety of indigenous names given to its species. The study of these names has provided the structure for guiding this ethnobotanic research.  相似文献   

9.
Two hundred and seventy nine patients suspected of having fungal lesions were examined. Skin scrapping, hair samples and nail clippings were collected from patients. Direct and culture examinations were performed for all samples. About 115 cases of examined subjects had dermatophytosis. Dermatophytosis occurred mainly in adults males (20–29 years). Tinea cruris (24.3%) was the most common type of dermatophytosis followed by tinea pedis (16.5%), tinea corporis (14.8%), tinea ungium (13%), tinea capitis (11.3%), tinea faciei (11.3%), tinea manuum (7%) and tinea barbae (1.7%). Trichophyton mentagrophytes was the most prevalent species followed by Epidermophyton floccosum.  相似文献   

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The most common hosts for the West Indian fruit fly, Anastrepha obliqua (Macquart) (Diptera: Tephritidae) are fruit in the family Anacardiaceae (mango [Mangifera L.] and mombin [Spondias L.] species). However, similar to many of the tropical fruit flies of major economic importance, this species attacks several other families of crop fruit, including Annonaceae (cherimoya, Annona cherimola Mill.), Myrtaceae (guava, Psidium L.), Oxalidaceae (carambola, Averrhoa carambola L.), Passifloraceae (granadilla, Passiflora quadrangularis Mill.), and Sapotaceae [mamey sapote, Pouteria sapota (Jacq.) H. E. Moore & Steam]. In the family Rutaceae the economically important genus Citrus has been reported and until recently considered a host for this fruit fly. In this study, we reviewed the taxonomy of A. obliqua, tested specific chemicals that may inhibit oviposition, compared egg-to-adult survival of A. obliqua on preferred hosts and on grapefruit (Citrus X paradisi Macfad.), and measured fruit tissue-specific developmental rates of A. obliqua and the known citrus breeding Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae), from egg to pupae. Our literature review shows much confusion concerning the taxonomy of this and related Anastrepha species, including synonymies and confusion with other species. The deterrent effect of the highest concentration of flavonoids for oviposition, although significant, was not absolute. Experiments carried out under laboratory conditions showed 15-40 times greater survival of A. ludens (whose preferred hosts include Rutaceae) on grapefruit compared with A. obliqua for both tree attached and harvested fruit. Experiments of survival of developing stages over time showed that the two species oviposit into different tissues in the fruit, and mortality is much higher for the West Indian fruit fly in the flavedo and albedo of the fruit compared with the Mexican fruit fly.  相似文献   

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Sandwich Harbour forms a largely enclosed bay and extensive lagoon system that receives a limited subsurface, freshwater inflow from the Kuiseb River. It has been suggested that the Kuiseb River contributed more freshwater to Sandwich Harbour in the past, and that the river has since been displaced northwards towards Walvis Bay. Pollen and diatom analyses were carried out on a trial core from the central inshore region of the harbour to determine whether sufficient biological material for extensive studies had been preserved, whether the sediments were undisturbed and whether changes in salinity were evident. Pollen was not preserved in sufficient quantities to analyse but diatoms were abundant in the upper portion of the core. Diatom analysis indicated that the sediments were relatively undisturbed. The earliest sediments were dominated by a freshwater soil flora, and this was displaced by a marine littoral flora with brackish and freshwater diatoms increasing in frequency in the uppermost sediments. The increase in brackish forms is correlated with the formation of a sandbar across the harbour at the end of the last century. Further analyses of the present day flora and sediment cores from different parts of the harbour should provide a clear indication of the history and development of the area, especially the role played by the Kuiseb River.  相似文献   

14.
Yosef  Reuven  Dabi  Hemant  Kumbhojkar  Swapnil 《Acta ethologica》2021,24(2):141-141
acta ethologica - A correction to this paper has been published: https://doi.org/10.1007/s10211-021-00367-w  相似文献   

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Genetic relationships among 15 South West European populations of Polyommatus coridon were evaluated by the electrophoretic study of 16 gene-enzyme systems. Nei's indexes I and D and other statistics demonstrated that two different species are involved, identifiable as Polyommatus coridon (six populations from Southern France and Italy) and Polyommatus caelestissimus (nine populations from Spain), respectively. The Spanish complex is characterized by a different genetic balance, involving much higher degree of interdemic differentiation. It also differs from populations from France and Italy on one alternative locus showing complete fixation. Species-level distinction is independent of haploid chromosome numbers that vary from 87 to 88 in both groups. An evaluation of selective pressures as operated by climatic factors was attempted. The Pleistocene radiation of this group and consequent patterns of the gene flow were reconstructed using spatial autocorrelation analysis.  相似文献   

19.
A new bothid flounder, Engyprosopon vanuatuensis, is described on the basis of 15 specimens (9 males and 6 females, 41.1–55.8mm in standard length) collected from deep waters (163–165m) off Vanuatu Island in 1994 during the French exploratory cruise MUSORSTOM 8. The new species clearly differs from its congeners in having a short body, big eyes, large scales, and many gill rakers without serrations. Remarkable sexual dimorphism appears in interorbital width, anterior curve of head profile, rostral and orbital spines, length of ocular-side pectoral fin, small dots on eyes, and pigmentation of blind-side body.  相似文献   

20.
A total of 7,334 crop and/or stomach contents from 239 species of South African birds were examined for ticks. Only 36 ticks were found: 24 in 21 cattle egret (Bubulcus ibis), four in four helmeted guineafowl (Numida meleagris), one in a crowned plover (Vanellus coronatus) and seven in a single lilacbreasted roller (Coracias caudata). In most cases identification of the ticks was not possible although the genera Boophilus, Hyalomma and Rhipicephalus were represented. With the exception of the oxpeckers which were not represented in this survey, we conclude that predation by birds on ticks is uncommon in South Africa.  相似文献   

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