Continuum Electromechanical Modeling of Protein-Membrane Interaction

A continuum electromechanical model is proposed to describe the membrane curvature induced by electrostatic interactions in a solvated protein-membrane system. The model couples the macroscopic strain energy of membrane and the electrostatic solvation energy of the system, and equilibrium membrane deformation is obtained by minimizing the electro-elastic energy functional with respect to the dielectric interface. The model is illustrated with the systems with increasing geometry complexity and captures the sensitivity of membrane curvature to the permanent and mobile charge distributions.Comment: 5 pages, 12 figure

Multi-stakeholder Platforms Strengthening Selection and use of Fodder Options in Ethiopia: Lessons and Challenges

N° ISBN - 978-2-7380-1284-5International audienceAlthough existing literature eloquently elaborates the role of an “innovation systems perspective” in rural development and provides theoretical insights into the concepts of the approach, there are few practical lessons emerging from application of the approach in research for development projects in various contexts. This paper analyzes a project designed to strengthen the ability of smallholders to innovate in ways that improved the returns to fodder use in Ethiopia. The paper applies an innovation systems perspective to the innovation process as a means of describing the contribution of a project-driven multi-stakeholder platform. A number of key lessons were gleaned from our research. Participatory selection of technologies that addressed farmers' priority problems and demonstrating tangible economic benefits were found to be effective in winning the trust of farmers and drawing the attention of a wider group of stakeholders. The benefits from the technologies needed to carry limited risk and accrue early economic gains to be attractive to farmers. Linking forage technologies with a range of value chain issues in livestock enterprises was essential for successful adoption of forage technologies by farmers. Engaging diverse actors in stakeholder platforms, including local decision makers, along the dairy/fattening value chain was found to be instrumental in turning the wealth of knowledge surrounding fodder technologies and practices into action and creating immediate benefits to poor livestock keepers. On the other hand we found that nurturing collective capacity of a network of organizations and individuals was a major challenge for small projects with limited mandate and resources. For sustainability, organizations with a long term commitment and strong decision-making power need to play a leading role in facilitating innovation processes. An effective agricultural innovation system requires a cadre of professionals with a new skill set and mind set (markets, agribusiness, rural institutions, rural microfinance, facilitation, system analysis, conflict management, etc.). This implies the need for research and development organizations to re-skill, and the need for the reform of university curricula to include skills in agribusiness, communication and partnership facilitation. Large scale institutional and policy change requires piloting of the concept and practices of facilitating innovation through stakeholder platforms in different contexts, documenting and sharing experiences, building on successes and engaging policy makers in the research process

Study on knowledge, attitude and dog ownership patterns related to rabies prevention and control in Addis Ababa, Ethiopia

The study was conducted from May 2003 to August 2003 in Addis Ababa with the objective of understanding the distribution of stray and owned dogs, dog ownership patterns and attitudes of people towards rabies and its prevention and control methods. A total of 2390 households were selected from 6 Sub Cities of Addis Ababa using stratified random sampling and were interviewed using structured questionnaires. From the total households interviewed, 969 (40.5%) of them were known to own one or more dogs, and the total number of owned dogs was estimated to be 225,078. Male dogs make up 1042 (78.4%) of the total owned dogs. Almost half of all the dogs 463 (47.8%) were tied only for some time during the day whereas 320 (33.1%) of the dogs were not tied at all and freely move from place to place and contribute to high dog bites in human beings and for the widespread occurrence of canine rabies in Addis Ababa. Six hundred fifty five (67.6%) of the interviewed households who owned dogs had a well fenced house. Most of the owned dogs 856 (88.4%) get their food from their owners and only 321 (33.3%) of the owners reported that they let their dogs to be vaccinated while the majority of the owners 644 (66.5%) do not let their dogs vaccinated regularly. A significant proportion of the interviewed households 2,323 (97.2%), (P < 0.05) indicated that they have the knowledge that dogs, cats and other animals can transmit rabies to humans and 1,752 (73.4%) of the households replied that rabies can be transmitted through bite, scratch and lick to open wounds. Analysis of the list of 2400 post exposure human antirabies treatments recorded at the EHNRI Zoonoses Laboratory from February 2002 to October 2003 showed that the most common animals involved in biting people were dogs. A total of 2198 (91.6%) people were bitten by dogs during the same period and most of them, 2053 (85.5%) were bitten on their hands and legs. All the above data indicated the need for a strong and coordinated rabies control activities to be conducted in the city

Characterization of Ethiopian mega hydrogeological regimes using GRACE, TRMM and GLDAS Datasets

Understanding the spatio-temporal characteristics of water storage changes is crucial for Ethiopia, a country that is facing a range of challenges in water management caused by anthropogenic impacts as well as climate variability. In addition to this, the scarcity of in situ measurements of soil moisture and groundwater, combined with intrinsic ‘‘scale limitations’’ of traditional methods used in hydrological characterization are further limiting the ability to assess water resource distribution in the region. The primary objective of this study is therefore to apply remotely sensed and model data over Ethiopia in order to (i) test the performance of models and remotely sensed data in modeling water resources distribution in un-gauged arid regions of Ethiopia, (ii) analyze the inter-annual and seasonal variability as well as changes in total water storage (TWS) over Ethiopia, (iii) understand the relationship between TWS changes, rainfall, and soil moisture anomalies over the study region, and (iv) identify the relationship between the characteristics of aquifers and TWS changes. The data used in this study includes; monthly gravity field data from the Gravity Recovery And Climate Experiment (GRACE) mission, rainfall data from the Tropical Rainfall Measuring Mission (TRMM), and soil moisture from the Global Land Data Assimilation System (GLDAS) model. Our investigation covers a period of 8 years from 2003 to 2011.The results of the study show that the western part and the north-eastern lowlands of Ethiopia experienced decrease in TWS water between 2003–2011, whereas all the other regions gained water during the study period. The impact of rainfall seasonality was also seen in the TWS changes. Applying the statistical method of Principal Component Analysis (PCA) to TWS, soil moisture and rainfall variations identified the dominant annual water variability in the western, north-western, northern, and central regions, and the dominant seasonal variability in the western, north-western, and the eastern regions. A correlation analysis between TWS and rainfall indicated a minimum time lag of zero to a maximum of six months, whereas no lag is noticeable between soil moisture anomalies and TWS changes. The delay response and correlation coefficient between rainfall and TWS appears to be related to recharge mechanisms, revealing that most regions of Ethiopia receive indirect recharge. Our results also show that the magnitude of TWS changes is higher in the western region and lower in the north-eastern region, and that the elevation influences soil moisture as well as TWS

Morphological Characterization of Goat Populations in Central Zone of Tigray, Ethiopia

Ethiopia has huge livestock resource, but poor in their productivity. It stated national small ruminant breeding policy and strategy focused on genetic improvement. This is intended to design appropriate breeding programs based on the indigenous breeds status. Study of phenotypic variation is among the prerequisite activities of genetic improvement that is limited in this study area. The objective of this study was to describe morphological characteristics and variations of goat populations in the Central zone of Tigray. Qualitative and quantitative data of 403 young to matured goats (326 lactating does and 77 bucks) were used to analyze by frequency procedure, GLM procedure, Pearson correlation, and multivariate analysis of SAS version 9.4. The study revealed that goats in Adwa district were distinct in coat colors and pattern, horn shape, ear orientation, head profile and ruff, significantly heavier (p<0.01) and larger (p<0.001) in height at withers and in height at pelvic than those in Tanqua Abergele (TA) and Kola Tembien (KT) districts. Goats found in Adwa district were morphologically distinct from those found in TA and KT districts with the higher discriminating values in female goats