Policy Brief: How to Promote Energy Efficiency and Energy Conservation in Ethiopia

In this policy brief we investigate a research question on " Why do households use energy efficient appliances and other energy conservation methods? How can adoption be improved in Ethiopia? " We provide insights from the energy systems development pathways for Ethiopia (PATHWAYS) project, based on a survey of urban households

Small ruminant production in coffee-based mixed crop-livestock system of Western Ethiopian Highlands: Status and prospectus for improvement

The study was conducted in Goma district of Jimma Zone of Ethiopia with the objectives of documenting the reasons why farmers in coffee dominant mixed-farming systems of western Ethiopia keep small ruminants, and identifying the constraints and opportunities for improvement of this sector. Results are based on diagnostic survey of 160 sample households, group discussions and personal observation. The study district was stratified into three groups based on flock distribution as: sheep dominating, goat dominating and mixed flock sites. The average land holding per household was 1.93 ha. In Goma where coffee and chat are the major cash sources for farmers, small ruminant are also primarily kept for cash generation as reported by 94% of the sampled households. The second main reason for keeping small ruminant in the study area was for saving mainly in time of coffee failure. Keeping small ruminants as a source of manure was the third important reason. From the interviewed households, 59.4, 32.1, 23.5, and 19.4% of them utilize communal grazing, aftermath grazing, roadside grazing, and riverside grazing, respectively for their animal as a sources of feed. Most small ruminants are either tethered or herded all the seasons due to the cultivation of perennial crops and predators. All small ruminants are housed for protection from adverse weather conditions and predators. The major problems for small ruminant production and marketing were: feed and grazing land shortage, lack of input, predators, diseases and parasites and marketing problems. In order to exploit the current growing demand of small ruminant meat at local and international markets, research and development interventions are required with regard to the identification of alternative feed resources and strategic feeding management, identification of causes of diseases and their control methods and improving marketing efficiency through appropriate policy

Stability analysis of homogenized stone column reinforced foundations using a numerical yield design approach

International audienceThis paper deals with the ultimate bearing capacity of soft clayey soils, rein-forced by stone columns, analyzed in the framework of the yield design theory. Since such geotechnical structures are almost impossible to analyze directly due to the strong heterogeneity of the reinforced soil, an alternative homogenization approach is advocated here. First, numerical lower and upper bound estimates for the macroscopic strength criterion of the stone column reinforced soil are approximated in a rigorous way with convex ellipsoidal sets, which makes the approximated criteria much easier to handle than the initial ones. Then, both static and kinematic approaches are carried out numerically on the homoge-nized problem using the above approximated macroscopic strength domains in an adapted finite element method. The whole numerical procedure is applied on one classical geotechnical problem: the ultimate bearing capacity of stone column reinforced foundations. The strength capacity of the structure is rigor-ously framed and the efficiency of the proposed numerical method is highlighted in terms of accuracy and calculation time

Observation on Variance and Covariance Estimates for Carcass Traits in Bull and Steer Progeny

Carcass measures from 970 cattle were collected at the Iowa State University Rhodes and McNay research farms over a 6-year period. Data were from bull and steer progeny of composite, Angus, and Simmental sires mated to three composite lines of dams. The objective of this study was to evaluate effects of sex differences on genetic parameter estimates for carcass traits. Estimation of genetic parameters using a threetrait mixed model showed differences between bulls and steers in h2 and genetic correlations. Heritability for carcass weight, percentage retail product, retail product weight, fat thickness, and longissimus muscle area from bull data were .43, .04, .46, .05, and .21, respectively. The corresponding values for steer data were in order of .32, .24, .40, .42, and .07, respectively. Furthermore, genetic correlations between some of the traits were different both in magnitude and direction when evaluated by sex. The results suggested possible differences in genetic parameter estimates between bulls and steer data. Hence, further study on effects of sex differences on genetic parameter estimation and a designing possible strategy to overcome the problem were emphasized

Phytophthora infestans Has a Plethora of Phospholipase D Enzymes Including a Subclass That Has Extracellular Activity

In eukaryotes phospholipase D (PLD) is involved in many cellular processes. Currently little is known about PLDs in oomycetes. Here we report that the oomycete plant pathogen Phytophthora infestans has a large repertoire of PLDs divided over six subfamilies: PXPH-PLD, PXTM-PLD, TM-PLD, PLD-likes, and type A and B sPLD-likes. Since the latter have signal peptides we developed a method using metabolically labelled phospholipids to monitor if P. infestans secretes PLD. In extracellular medium of ten P. infestans strains PLD activity was detected as demonstrated by the production of phosphatidic acid and the PLD specific marker phosphatidylalcohol

Long-Term Impacts of Stocking Rate on Soil Carbon Sequestration in Arid Areas of South Africa

Overstocking is one of the most important factors which results in changes of carbon stocks (Reeder and Schuman, 2002) and soil degradation, particularly in sandy soil, vulnerable to degradation through physical erosion. South African (RSA) topsoil is characterized by the low level of organic matter (Du Preez et al. 2011). Like most other African countries, little is known about the level of C sequestration under various grazing strategies in the vast dry grassland areas of RSA. It is well known that long-term studies with various stocking rate would be able to shed light on the level of C sequestration in varying soil types (Peneiro et al. 2010). Although studies have been undertaken concerning impacts of grazing on vegetation dynamics in RSA (Du Toit 2000), only few have focused on soil carbon stocks. Hence, this study was designed to assess impacts of long-term grazing at different stocking rate on carbon sequestration in Grootfontein, South Africa