Simple and low-cost drip irrigation system: An alternative approach to raise household farm productivity

Drip irrigationIrrigation designCrop production

Kinematic Modeling and Analysis of a Walking Machine (Robot) Leg Mechanism on a Rough Terrain

Many manmade machines and mechanisms including robots function based on the concept of nature-inspired design so that they can perform their intended duties by mimicking the working mechanisms of animals and insects. Accordingly, walking machines (robots) use wheels and tracks to cross rough terrain efficiently and in a stable way than more conventional robots. Legged walking robots in particular get a discontinuous contact with the ground that provides them the capability to select tractions such that obstacles or holes are escaped. This article reports a study conducted on kinematic modelling and analysis of a walking machine (robot) leg mechanism that can operate on rough terrain. Its kinematic mechanisms is analyzed using the Denavit-Hartenberg (DH) convention approach. Symbolic computations are also implemented to parametrically optimize the motion parameters of the robot leg mechanism. The equation of motion is derived from the dynamic analysis using the Euler-Lagrange method which involves kinetic and potential energy expressions. In order to validate the performance of the robot leg mechanism and motion behaviors, kinematic motion analysis in SolidWorks and MATLAB are used. The leg mechanism used is effective for rough terrain areas because it is capable of walking on terrain with different amplitudes due to surface toughness and aerodynamics.publishedVersio

Direct approach to the problem of strong local minima in Calculus of Variations

The paper introduces a general strategy for identifying strong local minimizers of variational functionals. It is based on the idea that any variation of the integral functional can be evaluated directly in terms of the appropriate parameterized measures. We demonstrate our approach on a problem of W^{1,infinity} weak-* local minima--a slight weakening of the classical notion of strong local minima. We obtain the first quasiconvexity-based set of sufficient conditions for W^{1,infinity} weak-* local minima.Comment: 26 pages, no figure

Capacity Gaps in Post Disaster Waste Management: Case Study in Sri Lanka

Disaster waste is one of the major consequences aftermath of any disaster, impacts on public and environment, rescue and emergency services, provision of lifeline support and socio-economic recovery of affected areas. Thus, management of wastes created by disasters has become an increasingly important issue to be addressed in responding to a disaster. This chapter intends to present the prevailing gaps in disaster waste management and approaches to minimize the impacts on disaster management at developing countries with special emphasis to Sri Lankan context. Findings revealed that, unavailability of single point responsibility and provisions for disaster waste in existing policies and capacity constraints of the prevailing peace time solid waste management practices as major capacity gaps. Establishment of a regulatory body and enforceable rules and regulations with necessary levels of capacities were identified with seven areas for capacity building for post disaster waste management. The research enabled to attain sustainable post disaster waste management for future resilience

Semi-Dwarf Tef Lines for High Seed Yield and Lodging Tolerance in Central Ethiopia

Tef [ Eragrostis tef (Zucc.) Trotter] is the major cereal crop in the Horn of Africa, especially in Ethiopia where it is a staple food for over 60% of its 90 million population. The crop performs better than other cereal crops under extreme environmental conditions. The grain of tef is not only nutritious but also gluten-free, the cause for celiac disease, which affects humans world wide. The objective of this study was to evaluate the morpho-agronomic performance of newly developed semi-dwarf tef genotypes for grain yield and yield related agronomic traits under diverse environmental conditions. Twenty-four tef lines were evaluated, along with one local and three standard checks, at three locations in the Central Ethiopia. The mean squares due to genotypes, locations and genotype by location interactions were highly significant (P<0.01) for all the studied traits. Three genotypes, namely RIL- 91, RIL-244 and RIL-11, gave the highest seed yield, ranging between 4.4 to 4.7 t ha-1, compared to the popular and widely cultivated tef variety called Quncho which gave 4.2 t ha-1. Genotypic and phenotypic coefficients of variations ranged from 0.002 to 173.9% and from 0.004 to 255.9%, respectively. The highest genetic advance (20.2 cm) and heritability estimates (86.7%) were obtained for plant height indicating that selection for this trait can be made easily. Grain yield showed significant and positive genotypic association with plant height, whole culm and second culm internode length, second culm internode diameter, number of spikelet per panicle and shoot biomass yield. Cluster analysis grouped the genotypes into six distinct classes. The first five principal components with eigenvalues greater than one accounted for 85% of the total variation. Generally, this study identified tef genotypes with better grain yield and reasonable lodging tolerance for further evaluation and eventual release to the farming communities.Tef [ Eragrostis tef (Zucc.) Trotter] est une\ua0culture majeure de c\ue9r\ue9ale dans la corne de l\u2019Afrique, particuli\ue8rement en Ethiopie o\uf9 elle est un aliment de base pour plus de 60% de son 90\ua0million de population. La culture performe mieux que d\u2019autres cultures c\ue9r\ue9ali\ue8res dans des conditions environnementales extr\ueames. Les grains du tef ne sont pas seulement nutritifs mais aussi ne contiennent pas de gluten, la cause des maladies des c\ue9r\ue9ales, qui affectent les hommes dans le monde. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer la performance morpho-agronomique des g\ue9notypes semi-nain de tef nouvellement d\ue9velopp\ue9s pour le rendement en grain et les composantes du rendement sous diverses conditions environnementales. Vingt-quatre lign\ue9es de tef \ue9taient \ue9valu\ue9es, ensemble avec un local et trois contr\uf4les standards, dans trois locations dans la r\ue9gion centrale de l\u2019Ethiopie. Les carr\ue9es moyens dus aux g\ue9notypes, locations et aux interactions entre le g\ue9notype et l\u2019environnement \ue9taient hautement significatifs (P<0.01) pour tous les traits \ue9tudi\ue9s. Trois g\ue9notypes, nomm\ue9s RIL-91, RIL-244 and RIL-11, ont donn\ue9 les rendements les plus \ue9lev\ue9s en grain variant de 4,4 \ue0 4,7 t ha-1, compar\ue9s \ue0 la vari\ue9t\ue9 de tef populaire et largement cultiv\ue9e appel\ue9e Ounho qui a donn\ue9 4,2 t ha-1. Les coefficients de variation g\ue9notypique et ph\ue9notypique ont vari\ue9 de 0,002 \ue0 173,9% et de 0,004 \ue0 255,9%, respectivement. La plus grande avanc\ue9e g\ue9notypique (20,2 cm) et les estimations d\u2019h\ue9ritabilit\ue9 (86,7%) \ue9taient obtenues pour la taille de la plante montrant que la s\ue9lection pour ce trait peut \ueatre faite plus t\uf4t. Le rendement en grain a montr\ue9 une association significative et positive avec la taille de la plante, la longueur de l\u2019entre-n\u153ud au niveau de la canne int\ue9grale et la seconde canne, le diam\ue8tre de la seconde canne de l\u2019entre-n\u153ud, le nombre d\u2019\ue9pillet par panicule et le rendement en biomasse de la tige. L\u2019analyse en class a group\ue9 les g\ue9notypes en six classes distinctes. Les cinq premi\ue8res composantes principales avec des valeurs propres sup\ue9rieures \ue0 un ont pris en compte 85% de la variation totale. En g\ue9n\ue9rale, cette \ue9tude a identifi\ue9 des g\ue9notypes de tef avec des meilleurs rendements en grains et de tol\ue9rance raisonnable \ue0 la verse pour davantage \ue9valuation et \ue9ventuelle lib\ue9ration aux communaut\ue9s paysannes

Factors related to discontinued clinic attendance by patients with podoconiosis in southern Ethiopia: a qualitative study

Background Podoconiosis is a lymphoedema of non-infectious cause which results in long-term ill health in affected individuals. Simple, effective treatment is available in certain parts of Ethiopia, but evidence indicates that not all patients continue collecting treatment supplies from clinic sites once started. We used qualitative techniques to explore factors related to discontinued attendance at outreach clinics of a non-government organization in southern Ethiopia. Methods A cross-sectional qualitative study was conducted in four clinic sites through unstructured in-depth interviews, key informant interviews and focus group discussions with the involvement of 88 study subjects. Results Discontinuation of clinic visits is common among podoconiosis patients. The reasons were: remoteness from the clinic sites, unrealistic expectation of ‘special’ aid, worry about increasing stigma, illness and misconceptions about treatment. Conclusions Several of these factors are remediable through community and individual information and education. Appropriate routes to deliver this information must be identified. Certain factors (such as distance to clinic sites and stigma) require substantial expansion of services or liaison with village-level government health services

Technology generation to dissemination:lessons learned from the tef improvement project

Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef\u2014an orphan crop important to the food security in the Horn of Africa, a region of the world with recurring devastating famines. We have established an efficient pipeline to bring improved tef lines from the laboratory to the farmers of Ethiopia. Of critical importance to the long-term success of this project is the cooperation among participants in Ethiopia and Switzerland, including donors, policy makers, research institutions, and farmers. Together, European and African scientists have developed a pipeline using breeding and genomic tools to improve the orphan crop tef and bring new cultivars to the farmers in Ethiopia. We highlight a new variety, Tesfa, developed in this pipeline and possessing a novel and desirable combination of traits. Tesfa\u2019s recent approval for release illustrates the success of the project and marks a milestone as it is the first variety (of many in the pipeline) to be released

Performance of Bt maize event MON810 in controlling maize stem borers Chilo partellus and Busseola fusca in Uganda

Stem borers are major insect pests of maize in Uganda. A study was conducted in 2014–2016 to assess the performance of Bt hybrids expressing Cry1Ab (event MON810) against the two major stem borer species in Uganda – the African stem borer (Busseola fusca) and the spotted stem borer (Chilo partellus) – under artificial infestation. The study comprised 14 non-commercialized hybrids, including seven pairs of Bt and non-Bt hybrids (isolines), three non-Bt commercial hybrids and a conventional stem borer resistant check. All stem borer damage parameters (leaf damage, number of internodes tunneled and tunnel length) were generally significantly lower in Bt hybrids than in their isolines, the conventionally resistant hybrid, and local commercial hybrids. Mean yields were significantly higher by 29.4–80.5% in the Bt hybrids than in the other three categories of non-Bt hybrids. This study demonstrated that Bt maize expressing Cry1Ab protects against leaf damage and can limit entry of stem borers into the stems of maize plants, resulting in higher yield than in the non-transgenic hybrids. Thus, Bt maize has potential to contribute to the overall management package of stem borers in Uganda