299 research outputs found

    Addis Ababa’s water crisis: challenges and opportunities

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    Addis Ababa’s water supply is insufficient to meet current needs, leading to intermittent water supplies which are increasing inequalities in water access depending on access to household storage and finances to develop private wells. Proposals to expand surface water storage will not fully meet the growing demand from the population and expanding industries. Groundwater depletion, land for expanding reservoir storage, water quality and unreliable energy supplies limit opportunities for increasing water provision. Action is needed now to better monitor and manage groundwater use, and to improve the conjunctive use of surface and groundwater to support sustainability for Addis Ababa’s water supplies

    Effect of intermittent aeration cycle on nutrient removal and microbial community in a fluidized bed reactor-membrane bioreactor combo system

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    Effect of intermittent aeration cycle (IAC=15/45-60/60min) on nutrient removal and microbial community structure was investigated using a novel fluidized bed reactor-membrane bioreactor (FBR-MBR) combo system. FBR alone was found more efficient for removing PO4-P (>85%) than NH4-N (98%). Efficient nitrification, stable mixed liquor suspended solid and reduced transmembrane pressure was also achieved. Quantitative real-time polymerase chain reaction results of total bacteria 16S rRNA gene copies per mL of mixed-liquor varied from (2.48±0.42)×109 initial to (2.74±0.10)×108, (6.27±0.16)×109 and (9.17±1.78)×109 for 15/45, 45/15 and 60/60min of IACs, respectively. The results of clone library analysis revealed that Proteobacteria (59%), Firmicutes (12%) and Bacteroidetes (11%) were the dominant bacterial group in all samples. Overall, the combo system performs optimum nutrient removal and host stable microbial communities at 45/15min of IAC. © 2014 Elsevier Ltd

    Lung function reduction and chronic respiratory symptoms among workers in the cement industry: a follow up study

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    <p>Abstract</p> <p>Background</p> <p>There are only a few follow-up studies of respiratory function among cement workers. The main aims of this study were to measure total dust exposure, to examine chronic respiratory symptoms and changes in lung function among cement factory workers and controls that were followed for one year.</p> <p>Methods</p> <p>The study was conducted in two cement factories in Ethiopia. Totally, 262 personal measurements of total dust among 105 randomly selected workers were performed. Samples of total dust were collected on 37-mm cellulose acetate filters placed in closed faced Millipore-cassettes. Totally 127 workers; 56 cleaners, 44 cement production workers and 27 controls were randomly selected from two factories and examined for lung function and interviewed for chronic respiratory symptoms in 2009. Of these, 91 workers; 38 cement cleaners (mean age 32 years), 33 cement production workers (36 years) and 20 controls (38 years) were examined with the same measurements in 2010.</p> <p>Results</p> <p>Total geometric mean dust exposure among cleaners was 432 mg/m<sup>3</sup>. The fraction of samples exceeding the Threshold Limit Value (TLV) of 10 mg/m<sup>3 </sup>for the cleaners varied from 84-97% in the four departments. The levels were considerably lower among the production workers (GM = 8.2 mg/m<sup>3</sup>), but still 48% exceeded 10 mg/m<sup>3</sup>.</p> <p>The prevalence of all the chronic respiratory symptoms among both cleaners and production workers was significantly higher than among the controls.</p> <p>Forced Expiratory Volume in one second (FEV<sub>1</sub>) and FEV<sub>1</sub>/Forced Vital Capacity (FEV<sub>1</sub>/FVC) were significantly reduced from 2009 to 2010 among the cleaners (p < 0.002 and p < 0.004, respectively) and production workers (p < 0.05 and p < 0.02, respectively), but not among the controls.</p> <p>Conclusions</p> <p>The high prevalence of chronic respiratory symptoms and reduction in lung function is probably associated with high cement dust exposure. Preventive measures are needed to reduce the dust exposure.</p

    Evaluation of legumes for fermentability and protein fractions using in vitro rumen fermentation

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    Diversifying feed with non-traditional options could minimize the dependency on traditional sources, maintain the feed supply throughout the year, and potentially reduce the cost of raising animals. A total of eight forage legumes including Peltophorum pterocarpum, Neptunia monosperma, Vachellia sutherlandii (Corkwood), Gliricidia sepium, Bauhinia hookeri and three Desmanthus species (JCU4, JCU5 and JCU9) were collected to assess their in vitro fermentability, degradable and undegradable protein fractions using in vitro gas production method. Soybean meal and lucerne hay were used as control. The total gas production ranged from 12.8 mL/g in P. pterocarpum to 127.3 mL/g in soybean meal. The total volatile fatty acid (VFA) concentration from G. sepium (117.7 mM/L) and V. sutherlandii (111.3 mM/L) were larger than other legumes except for soybean meal (157.1 mM/L) and lucerne hay (130.4 mM/L), P < 0.001. The methane gas produced from B. hookeri and P. pterocarpum (0.39 and 0.32 mL/g) was lower than other feeds, P < 0.001. The V. sutherlandii (720 g/kg crude protein (CP)) and G. sepium (745 g/kg CP) had the greatest effective CP degradation (EPD) than other legume species examined, P < 0.001, which was approaching that measured in the control samples. The amount of protein fraction ‘a’ (rapidly degradable) was larger in JCU9 (551 g/kg CP), and G. sepium (472 g/kg CP), and lower in B. hookeri (10.9 g/kg CP) and P. pterocarpum (14.8 g/kg CP), P < 0.001. The V. sutherlandii (386 g/kg CP) and G. sepium (272 g/kg CP) exceeded other legumes in the proportion of fraction ‘b’ (slowly degradable), P < 0.001, but not the controls. The undegradable fraction increased with increasing phenolic content and reached more than 940 g/kg CP for both B. hookeri and P. pterocarpum. The Desmanthus cultivars showed intermediate values among the tested legumes in fermentation characteristics and shows potential to provide slowly degradable protein while reducing methane. The findings indicate the possibility of using V. sutherlandii and G. sepium to substitute other forages for their greater slowly degradable protein content. Moreover, B. hookeri and P. pterocarpum plants emerged as candidates to assist protein protection in the rumen and reduce methane emissions. However, these legumes need to be evaluated in vivo before promoting for further use to confirm the variability reported here

    Effectiveness of a simple lymphoedema treatment regimen in podoconiosis management in southern Ethiopia: one year follow-up

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    Background: Podoconiosis is a non-filarial elephantiasis caused by long-term barefoot exposure to volcanic soils in endemic areas. Irritant silicate particles penetrate the skin, causing a progressive, debilitating lymphoedema of the lower leg, often starting in the second decade of life. A simple patient-led treatment approach appropriate for resource poor settings has been developed, comprising (1) education on aetiology and prevention of podoconiosis, (2) foot hygiene (daily washing with soap, water and an antiseptic), (3) the regular use of emollient, (4) elevation of the limb at night, and (5) emphasis on the consistent use of shoes and socks. Methodology/Principal Findings: We did a 12-month, non-comparative, longitudinal evaluation of 33 patients newly presenting to one clinic site of a non-government organization (the Mossy Foot Treatment & Prevention Association, MFTPA) in southern Ethiopia. Outcome measures used for the monitoring of disease progress were (1) the clinical staging system for podoconiosis, and (2) the Amharic Dermatology Life Quality Index (DLQI), both of which have been recently validated for use in this setting. Digital photographs were also taken at each visit. Twenty-seven patients completed follow up. Characteristics of patients completing follow-up were not significantly different to those not. Mean clinical stage and lower leg circumference decreased significantly (mean difference -0.67 (95% CI -0.38 to -0.96) and -2.00 (95% CI -1.26 to -2.74), respectively, p<0.001 for both changes). Mean DLQI diminished from 21 (out of a maximum of 30) to 6 (p<0.001). There was a non-significant change in proportion of patients with mossy lesions (p = 0.375). Conclusions/Significance: This simple, resource-appropriate regimen has a considerable impact both on clinical progression and self-reported quality of life of affected individuals. The regimen appears ideal for scaling up to other endemic regions in Ethiopia and internationally. We recommend that further research in the area include analysis of cost-effectiveness of the regimen

    Electrocatalytic reduction of carbon dioxide on gold–copper bimetallic nanoparticles: Effects of surface composition on selectivity

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    In this work, bimetallic nanoparticles (NPs) of Au and Cu are synthesized for the electrochemical reduction reaction of CO2 (CO2RR). It is known that the binding strength between the reduction intermediates and the electrocatalyst affects the selectivity of products, but how to correlate the performance with the surface composition, structure, and properties of a bimetallic electrocatalyst, instead of stoichiometric or bulk composition remains less discussed. AuCu and AuCu3 NPs with the size around similar to 8 nm were prepared. By excluding the size effect, the work studies the effects of surface composition and heteroatomic interaction on the selectivity and faradaic efficiency of the reduction products. Based on X-ray absorption spectroscopy (XAS), one can quantify the alloying extent and surface compositions of electrocatalysts, which are supposed to have the pivotal effects on the reaction pathways and the corresponding reduction products. It is found that high activity and notably improved CO selectivity of Au-Cu bimetallic NPs can be attributed to the heterometallic coordination and their electronic interactions. The reduction products were analyzed by gas chromatography and nuclear magnetic resonance (NMR) spectroscopy. Nearly 60 mA cm(-2) of current density was recorded at -0.91 V vs. RHE, and selectivity of 78 +/- 4.3% CO was obtained using AuCu. (C) 2020 Published by Elsevier Ltd

    A morphological study of galaxies in ZwCl0024+1652, a galaxy cluster at redshift z ∼ 0.4

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    ABSTRACT: he well-known cluster of galaxies ZwCl0024+1652 at z ∼ 0.4 lacks an in-depth morphological classification of its central region. While previous studies provide a visual classification of a patched area, we used the public code called galaxy Support Vector Machine GALSVM) and HST/ACS data as well as the WFP2 master catalogue to automatically classify all cluster members up to 1 Mpc. GALSVM analyses galaxy morphologies through support vector machine (SVM). From the 231 cluster galaxies, we classified 97 as early types (ETs) and 83 as late types (LTs). The remaining 51 stayed unclassified (or undecided). By cross-matching our results with the existing visual classification, we found an agreement of 81 per cent. In addition to previous Zwcl0024 morphological classifications, 121 of our galaxies were classified for the first time in this work. In addition, we tested the location of classified galaxies on the standard morphological diagrams, colour–colour and colour–magnitude diagrams. Out of all cluster members, ∼20 per cent are emission-line galaxies, taking into account previous GLACE results. We have verified that the ET fraction is slightly higher near the cluster core and decreases with the clustercentric distance, while the opposite trend has been observed for LT galaxies. We found a higher fraction of ETs (54 per cent) than LTs (46 per cent) throughout the analysed central region, as expected. In addition, we analysed the correlation between the five morphological parameters (Abraham concentration, Bershady–Concelice concentration, asymmetry, Gini, and M20 moment of light) and the clustercentric distance, without finding a clear trend. Finally, as a result of our work, the morphological catalogue of 231 galaxies containing all the measured parameters and the final classification is available in the electronic form of this paper.MP also acknowledges support from the Spanish MINECO under projects AYA2013-42227-P and AYA2016-76682-C3-1-P- This work was supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under the grants AYA2014-58861-C3-2-P, AYA2014-58861-C3-3-P, AYA2017-88007-C3-1-P, and AYA2017-88007-C3-2-P

    Effect of a self-care educational intervention to improve self-care adherence among patients with chronic heart failure: a clustered randomized controlled trial in Northwest Ethiopia

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    Background: As the burden of cardiovascular disease increases in sub-Saharan Africa, there is a growing need for low-cost interventions to mitigate its impact. Providing self-care health education to patients with chronic heart failure (CHF) is recommended as an intervention to prevent complications, improve quality of life, and reduce financial burdens on fragile health systems. However, little is known about health education’s effectiveness at improving CHF self-management adherence in sub-Saharan Africa. Therefore the present study aimed to assess the effectiveness of an educational intervention to improve self-care adherence among patients with CHF at Debre Markos and Felege Hiwot Referral Hospitals in Northwest Ethiopia. Methods: To address this gap, we adapted a health education intervention based on social cognitive theory comprising of intensive four-day training and, one-day follow-up sessions offered every four months. Patients also received illustrated educational leaflets. We then conducted a clustered randomized control trial of the intervention with 186 randomly-selected patients at Debre Markos and Felege Hiwot referral hospitals. We collected self-reported data on self-care behavior before each educational session. We analyzed these data using a generalized estimating equations model to identify health education's effect on a validated 8-item self-care adherence scale. Results: Self-care adherence scores were balanced at baseline. After the intervention, patients in the intervention group (n = 88) had higher adherence scores than those in the control group (n = 98). This difference was statistically significant (β = 4.15, p < 0.05) and increased with each round of education. Other factors significantly associated with adherence scores were being single (β = − 0.25, p < 0.05), taking aspirin (β = 0.76, p < 0.05), and having a history of hospitalization (β = 0.91, p < 0.05). Conclusions: We find that self-care education significantly improved self-care adherence scores among CHF patients. This suggests that policymakers should consider incorporating self-care education into CHF management
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