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111.
D Grace J Monda N Karanja TF Randolph EK Kang'ethe 《Tropical animal health and production》2012,44(Z1):33-40
We carried out a participatory risk assessment to estimate the risk (negative consequences and their likelihood) from zoonotic Cryptosporidium originating in dairy farms in urban Dagoretti, Nairobi to dairy farm households and their neighbours. We selected 20 households at high risk for Cryptosporidium from a larger sample of 300 dairy households in Dagoretti based on risk factors present. We then conducted a participatory mapping of the flow of the hazard from its origin (cattle) to human potential victims. This showed three main exposure pathways (food and water borne, occupational and recreational). This was used to develop a fault tree model which we parameterised using information from the study and literature. A stochastic simulation was used to estimate the probability of exposure to zoonotic cryptosporidiosis originating from urban dairying. Around 6?% of environmental samples were positive for Cryptosporidium. Probability of exposure to Cryptosporidium from dairy cattle ranged from 0.0055 for people with clinical acquired immunodeficiency syndrome in non-dairy households to 0.0102 for children under 5?years from dairy households. Most of the estimated health burden was born by children. Although dairy cattle are the source of Cryptosporidium, the model suggests consumption of vegetables is a greater source of risk than consumption of milk. In conclusion, by combining participatory methods with quantitative microbial risk assessment, we were able to rapidly, and with appropriate 'imprecision', investigate health risk to communities from Cryptosporidium and identify the most vulnerable groups and the most risky practices. 相似文献
112.
113.
Kangethe Erastus Kimani Violet Grace Delia Mitoko Grace McDermott Brigid Ambia Julie Nyongesa Concepta Mbugua Gabriel Ogara William Obutu Peninnah 《Tropical animal health and production》2012,44(1):41-46
This paper describes a trans-disciplinary process of co-generating and disseminating evidence-based messages for reducing the risk from cryptosporidiosis and other zoonoses in an urban community in Nairobi. Research findings about disease prevalence, risk factors and observed risky and risk-mitigating practices were analysed by a team comprising researchers, community members and local policy- and decision-makers. Using participatory planning, multiple strategies were developed for disseminating key information. We identified five vulnerable groups at higher risk of exposure to cryptosporidiosis and other cattle zoonoses with similar transmission pathways (women, children, elderly people, immunosuppressed people and male farm workers). For each group, targeted messages were developed. Good practices already in use, as were also practices as practices to improve environmental conditions. These messages were disseminated through printed material, in a workshop, through community campaigners and also an edutainment soap opera episode broadcast on Kenyan television. In conclusion, a participatory and trans-disciplinary process can help transform the findings of research into messages that are targeted, attractive and understandable. 相似文献
114.
Nyangaga Julius N. Grace Delia Kimani Violet Kiragu Monica W. Langat Alfred K. Mbugua Gabriel Mitoko Grace Kangethe Erastus K. 《Tropical animal health and production》2012,44(1):47-51
A study was undertaken to investigate and mitigate the risk from zoonotic Cryptosporidium associated with dairy farming in Dagoretti division, Nairobi, Kenya. Outcome mapping (OM), a relatively new tool for planning and evaluation, was used to foster and then monitor changes in farmer management of health risks. Elements of the OM framework, including the vision, mission and expected progress markers, were developed in participatory sessions and a set of progress markers was used for monitoring behaviour change in farmers participating in the project (the boundary partners). Behaviour change (the outcome challenge) was supported by a range of awareness and educational campaigns, working with strategic partners (extension agents and administrative leaders). The farmers the project worked with made considerable progress according to the markers; they demonstrated an understanding of cryptosporidiosis, established or maintained clean and well drained cattle sheds, and took conscious effort to reduce possible infection. Farmers who did not participate in the project (non-contact farmers) were found to be less advanced on the progress marker indicators. Non-contact farmers who carried out risk-reducing practices had done so independently of the project team. The administration leaders, as strategic partners, had a positive attitude towards the project and confidence in their ability to support project objectives. The study demonstrates the utility of OM in helping to identify and support behavioural change. 相似文献
115.
Grace Delia Olowoye Janice Dipeolu Morenike Odebode Stella Randolph Thomas 《Tropical animal health and production》2012,45(1):53-57
Four Newcastle disease virus isolates were recovered from asymptomatic guinea fowl (Numida meleagris galeata) and Muscovy ducks (Cariana moscata). For the purpose of molecular identification and phylogeny, phylogenetic characterization was performed to identify the pathotypes. All four viruses had a cleavage motif 112RRQKRF117 which is characteristic of virulent strains. The isolates grouped with viruses previously reported as sub-lineage 5g from chickens in Nigeria. This study report for the first time the identification of the virulent sub-lineage 5g Newcastle disease virus from apparently healthy guinea fowl and domestic ducks in Nigeria, and since infections were sub-clinical, it suggest that these species could play a role in the spread and transmission of virulent Newcastle disease virus that can infect other poultry. The isolation and identification of virulent Newcastle disease virus in these unusual hosts and the high sequence similarity (99.3–100 %) between viruses in this study with strains reported for Niger and Cameroun gives insights into the ecology of virulent Newcastle disease viruses and suggests some cross-border movement and trade in live poultry. 相似文献
116.
Changes in land use in the Orinoco lowlands affect the daily trends of energy and water vapor fluxes. We analyzed these fluxes along a disturbance gradient beginning from a cultivated tall-grass Andropogon field (S1) and extending over three savanna sites with increasing woody cover over herbaceous vegetation. The savanna sites encompass a herbaceous savanna (S2), a tree savanna (S3) and a woodland savanna (S4). In the wet season, there were differences in the radiation budget: seasonally averaged albedo for S1 (0.17) exceeded that of S2-S4 (0.13-0.14). Eddy covariance fluxes indicate that the partitioning of the daily net radiation (Rn) into sensible and latent heat (lambda E) fluxes depends on land use. During the wet season, evapotranspiration (i.e., lambda E) over the S1-S4 sites accounted for a variable fraction of Rn (i.e., 0.75, 0.52, 0.67 and 0.68, respectively). Therefore, the Bowen ratio was typically below 1. As the dry season progressed, the lambda E/Rn ratio decreased markedly with increasing air and canopy temperatures and air humidity mole fraction deficit. The maximum evaporation rate over the S1-S4 sites was 3.2, 2.5, 3.5 and 4.1 mm day(-1), respectively, and the annual values were 721, 538, 771 and 732 mm year(-1), respectively, equivalent to 49, 65, 52 and 88% of the rainfall. Soil water content fell from a maximum above 0.28 in the wet season to 0.030, 0.026, 0.030 and 0.028 m(3) m(-3) at sites S1-S4, respectively, in the dry season. Leaf area index was greatly reduced as herbaceous vegetation dried out. 相似文献
117.
Rebecca Ibach Marek Gnatowski Grace Sun Jessie Glaeser Mathew Leung John Haight 《Wood material science & engineering》2018,13(2):81-96
The flexural properties of wood–plastic composite (WPC) deck boards exposed to 9.5 years of environmental decay in Hilo, Hawaii, were compared to samples exposed to moisture and decay fungi for 12 weeks in the laboratory, to establish a correlation between sample flexural properties and calculated void volume. Specimens were tested for flexural strength and modulus, both wet and dry, at 23°C and 52°C. Some specimens degenerated to only 15% of original flexural strength. UV radiation had no impact on flexural properties of field-exposed boards; loss occurred mainly on the side opposite to the sun-exposed surface. The mechanism of the aging process on colonization of WPC by fungi was examined and is consistent with development of slow crack growth in the polyethylene matrix combined with wood decay by fungi. Wood particle decay, moisture, and elevated temperature were the major factors causing composite degradation, indicated by accumulation of voids and a severe decrease in flexural properties. To simulate long-term field impact (including decay) on WPC flexural properties in the laboratory, conditioning of specimens in hot water for an extended period of time is required. Exposure to water (70°C/5 days) was adequate for simulating long-term composite exposure in Hawaii of 4?×?15?×?86 mm3 specimens. 相似文献
118.
Raphael Kwame Kavi Kwabena Asiedu Bugyei Grace Obeng-Koranteng Benjamin Yao Folitse 《Journal Of Agricultural & Food Information》2018,19(2):176-191
This study assessed information sources for urban mushroom farmers in Accra, Ghana. One hundred farmers were sampled, and a structured questionnaire was administered to solicit information from the respondents. Results showed that the majority of farmers were male (71%) and most (60%) with university education. The majority (44%) had 1–5 years of experience in mushroom cultivation. Co-farmers (89.8%), the Mushroom Growers Association (79.6%), training workshops (73.5%), and the Farmers' Forum (29.6%) readily served as information sources for farmers. The research revealed that, for 52% of farmers, ignorance of information sources was a major hindrance in their quest for information. 相似文献
119.
120.
Grace M. Nisola Arnel B. Beltran Viava Jane L. Africa Eulsaeng Cho Midoek Han Wook-Jin Chung 《Fibers and Polymers》2011,12(5):572-579
Two types of modifications were performed on a commercial polyimide (PI) hollow fiber membrane for carbon dioxide (CO2) and methane (CH4) gas permeations. Thermal annealing was conducted between 50- and 200 °C while chemical cross-linking was performed using
0.1- to 1.0 wt% of N, (1-Naphthyl) ethylene-diamine dihydrochloride (NED). Membrane characterization revealed densification
of the thermally annealed PIs. But formation of macrovoids was observed in PIs annealed near its glass transition temperature
(207 °C). Fourier transform infrared spectroscopy confirmed the successful cross-linking of NED with PI. Highest CO2 permeance was obtained from pristine PI (P/L=225 GPU) but it also had the lowest selectivity (α=72). The performances of thermally annealed (P/L=160–219 GPU, α=76–106), NED crosslinked (P/L=68–139 GPU, α=65–95) and thermally induced NED cross-linked (P/L=51-91 GPU, α=98–138) PIs varied according to modification conditions. Among the modified membranes, highest CO2 permeance was obtained from thermally annealed PI at 100 °C (P/L=211GPU, α=106) while thermally induced NED cross-linked PI (100 °C, 0.5 wt% NED) exhibited the highest selectivity (P/L=91, α=138). Both modified membranes are the best candidates for CO2/CH4 separation. 相似文献