Efficacy and Costs of Handheld Sprayers in the Subhumid Savanna for Cogongrass Control

2005 ◽  
Vol 19 (3) ◽  
pp. 568-574 ◽  
Author(s):  
Ole K. Nielsen ◽  
David Chikoye ◽  
Jens C. Streibig
Keyword(s):  
Sub Saharan Africa ◽  
Response Curves ◽  
Knapsack Sprayer ◽  
Sub Saharan ◽  
High Doses ◽  
Hand Weeding ◽  
Carrier Volume ◽  
User Friendly ◽  
On Farm ◽  
Very High

Cogongrass continues to be one of the most invasive weeds in the subhumid savanna. Herbicide application expenses depend on equipment costs, costs of water transport for spraying, and chemical costs. In three on-farm experiments on land heavily infested with cogongrass, the effectiveness of a knapsack sprayer (KS), a very low volume sprayer (VLV), and a rope wick (RW) applicator was tested at Ijaye, Nigeria, from 2000 to 2001. The sprayers differed in application method, price, and carrier volume required. The dose–response curves for the three applicators were identical in all parameters except at very high doses for the RW. Consequently, there were no apparent differences in glyphosate effectiveness, even when it was applied with different equipment and different carrier volumes. However, even at very high doses, the RW was not as efficient as was the KS and VLV. Actual biomass reduction of cogongrass was greater with the KS and VLV. Even though the KS and VLV generally gave better control levels than the RW, the latter is more user-friendly because it does not require protective masks, which are often unavailable in sub-Saharan Africa. In a situation with labor scarcity, weeding with the RW was cheaper than hand weeding with hoes. The VLV was more economical when used on areas larger than 10 ha than was the RW. The KS was more economical than all other methods when used on areas larger than 2 ha.

scholarly journals Production And Use Of A Shelf-Stable Bovine Blood Powder For Food Fortification As A Food-Based Strategy To Combat Iron Deficiency Anaemia In Sub-Saharan Africa

2005 ◽  
Vol 05 (01) ◽  
pp. 01-18
Author(s):  
JK Kikafunda ◽  
◽  
P Sserumaga ◽  
Keyword(s):  
Developing Countries ◽  
Iron Deficiency ◽  
Iron Deficiency Anaemia ◽  
Sub Saharan Africa ◽  
Bovine Blood ◽  
High Concentration ◽  
Deficiency Anaemia ◽  
Sub Saharan ◽  
Shelf Stable ◽  
Very High

Iron deficiency anaemia (IDA) is the most widespread micro-nutrient deficiency disease world-wide, particularly in developing countries. Although there are several strategies to combat IDA, food-based strategies are the most sustainable and yet little research has been carried out in this area. The study aimed at developing a technology for processing and preserving bovine blood into a shelf-stable powder, which would easily be utilised in fortifying commonly consumed food items, as a food-based strategy in the fight against iron deficiency anaemia. A shelf-stable powder was processed from fresh bovine blood and the physical, chemical, microbiological and shelf-life characteristics assessed using conventional methods. The results of the chemical analysis showed that bovine blood powder has a very high concentration of haeme iron at 195.46 mg/100g of powder. This is more than ten times the level of iron in bovine liver, one of the most commonly used food source of haeme iron whose iron content is only 17 mg/100gm of liver. Although microbiological tests carried out on the freshly processed blood powder and on the same powder after one and three months of storage at room temperature found a significant rise in yeast, mould and total plate counts, these values were low and within safe limits. The blood powder was used to fortify a bean sauce. Sensory analysis panellists considered the fortified bean sauce moderately acceptable with a mean score of 4.667 (like slightly) compared to a mean score of 2.333 (like very much) for the non-fortified sauce, on a nine point Hedonic scale. These findings show that processed bovine blood powder has very high levels of haeme iron and thus has great potential as a food-based strategy to combat iron-deficiency anaemia in resource-poor developing countries, particularly those in sub-Saharan Africa. However, more research is needed to improve the microbiological and sensory characteristics of the blood powder.

On-farm rice yield and its association with biophysical factors in sub-Saharan Africa

2017 ◽  
Vol 85 ◽  
pp. 1-11 ◽  
Author(s):  
Atsuko Tanaka ◽  
Jean-Martial Johnson ◽  
Kalimuthu Senthilkumar ◽  
Cyriaque Akakpo ◽  
Zacharie Segda ◽  
...  
Keyword(s):  
Rice Yield ◽  
Sub Saharan Africa ◽  
Biophysical Factors ◽  
Sub Saharan ◽  
On Farm

scholarly journals Labor-Saving Weed Technologies for Lowland Rice Farmers in sub-Saharan Africa

2015 ◽  
Vol 29 (4) ◽  
pp. 751-757 ◽  
Author(s):  
Jonne Rodenburg ◽  
Kazuki Saito ◽  
Runyambo Irakiza ◽  
Derek W. Makokha ◽  
Enos A. Onyuka ◽  
...  
Keyword(s):  
Weed Control ◽  
Weed Management ◽  
Sub Saharan Africa ◽  
Herbicide Application ◽  
Control Efficacy ◽  
Rice Farmers ◽  
Time Requirements ◽  
Rice Yields ◽  
Sub Saharan ◽  
Hand Weeding

Time requirements, weed control efficacy, and yield effects of three labor-saving weed technologies were tested against hand weeding during three seasons in 2012 and 2013. The technologies included two hand-operated mechanical weeders, the straight-spike and the twisted-spike floating weeder, and the PRE application of oxadiazon. The straight-spike floating weeder reduced weeding time by 32 to 49%, the twisted-spike floating weeder reduced weeding time by 32 to 56%, and the application of herbicide required 88 to 97% less time than hand weeding. Herbicide application provided the best weed control in two of the three seasons. No differences in weed control efficacy were observed between mechanical and hand weeding. Yield differences were only observed in season 3 with higher rice yields after PRE application of oxadiazon compared with other weed management treatments.

EVALUATING PYRETHROID ALTERNATIVES FOR THE MANAGEMENT OF COTTON BOLLWORMS AND RESISTANCE IN CAMEROON

2009 ◽  
Vol 45 (1) ◽  
pp. 35-46 ◽  
Author(s):  
J. ACHALEKE ◽  
M. VAISSAYRE ◽  
T. BREVAULT
Keyword(s):  
Pyrethroid Resistance ◽  
Resistance Management ◽  
Sub Saharan Africa ◽  
Cross Resistance ◽  
Cotton Production ◽  
Suitable Alternative ◽  
Early Peak ◽  
Sub Saharan ◽  
On Farm ◽  
Cotton Pest

SUMMARYIn sub-Saharan Africa, the bollworm complex, including Helicoverpa armigera, Diparopsis watersi and Earias spp., threatens the continued success of cotton production. Pyrethroid resistance in H. armigera led to serious crop losses while endosulfan, a suitable alternative to pyrethroids, was banned for cotton pest management. Five candidates with no cross-resistance to pyrethroids were evaluated in both on-station and on-farm trials from 2002 to 2006. Two applications were made at the early peak of H. armigera infestation in September, the period when pyrethroid use should be restricted for resistance management purposes. Results showed that, as expected, bollworm infestation consistently peaked from mid-September to mid-October. Spinosad, thiodicarb and emamectin-benzoate were the most suitable alternatives to reduce damage, regardless of the cotton bollworm species. Indoxacarb and lufenuron were less effective in controlling D. watersi. On-farm experiments confirmed the suitability of spinosad for control of pyrethroid-resistant H. armigera, particularly on late sown fields. These new chemistries offer control of bollworms which justify their relevance for pyrethroid resistance management in Cameroon and sub-Saharan Africa.

scholarly journals Prevalence of dementia in Colombian populations

2014 ◽  
Vol 8 (4) ◽  
pp. 323-329 ◽  
Author(s):  
Efraín Amaya Vargas ◽  
Ángela Magnolia Ríos Gallardo ◽  
Guillermo González Manrrique ◽  
Lina M. Murcia-Paredes ◽  
María Consuelo Angarita Riaño ◽  
...  
Keyword(s):  
Gradual Increase ◽  
Scientific Progress ◽  
Sub Saharan Africa ◽  
High Rate ◽  
High Prevalence ◽  
Sub Saharan ◽  
The City ◽  
Very High ◽  
The U.S ◽  
Prevalence Of Dementia

With the gradual increase in the life expectancy of the population due to scientific progress and public health at the service of society, the prevalence of dementia has been increasing at different rates worldwide. Currently, the prevalence rates range between 5% and 7% (6.4% in the U.S. and up to 8.5 % in Latin America) in subjects older than 60 years. The lowest prevalence rate (2.1%) has been reported from sub-Saharan Africa, probably due to selective mortality under 60 years of age. By contrast, a very high prevalence of dementia (23.6% dementia in individuals ≥60 years) was observed in the city of Neiva, Southern Colombia. We believe that this high rate could be explained by the presence of several risk factors such as very low schooling, low socio-economic strata, chronic diseases, the inclusion of geriatric homes among others, and additional unknown factors.

scholarly journals Using mobile phone data to reveal risk flow networks underlying the HIV epidemic in Namibia

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Eugenio Valdano ◽  
Justin T. Okano ◽  
Vittoria Colizza ◽  
Honore K. Mitonga ◽  
Sally Blower
Keyword(s):  
Large Scale ◽  
Control Strategies ◽  
Sub Saharan Africa ◽  
Mobile Phone Data ◽  
Mathematical Framework ◽  
Sub Saharan ◽  
Administrative Units ◽  
Large Scale Networks ◽  
Living With Hiv ◽  
Very High

AbstractTwenty-six million people are living with HIV in sub-Saharan Africa; epidemics are widely dispersed, due to high levels of mobility. However, global elimination strategies do not consider mobility. We use Call Detail Records from 9 billion calls/texts to model mobility in Namibia; we quantify the epidemic-level impact by using a mathematical framework based on spatial networks. We find complex networks of risk flows dispersed risk countrywide: increasing the risk of acquiring HIV in some areas, decreasing it in others. Overall, 40% of risk was mobility-driven. Networks contained multiple risk hubs. All constituencies (administrative units) imported and exported risk, to varying degrees. A few exported very high levels of risk: their residents infected many residents of other constituencies. Notably, prevalence in the constituency exporting the most risk was below average. Large-scale networks of mobility-driven risk flows underlie generalized HIV epidemics in sub-Saharan Africa. In order to eliminate HIV, it is likely to become increasingly important to implement innovative control strategies that focus on disrupting risk flows.

scholarly journals Immigrant Children and the Internet in Spain: Uses, Opportunities, and Risks

2019 ◽  
Vol 7 (1) ◽  
pp. 56-65 ◽  
Author(s):  
Miguel Angel Casado ◽  
Carmelo Garitaonandia ◽  
Gorka Moreno ◽  
Estefania Jimenez
Keyword(s):  
Qualitative Methodology ◽  
Immigrant Children ◽  
Sub Saharan Africa ◽  
High Rate ◽  
The Internet ◽  
Foreign Born ◽  
Smartphone Use ◽  
Sub Saharan ◽  
Depth Interviews ◽  
Very High

This article describes the use made of the Internet by immigrant children living in Spain and the opportunities and risks it involves. Specifically, it deals with children from the Maghreb, Ecuador, and Sub-Saharan Africa, three regions which account for a quarter of Spain’s foreign-born population. A qualitative methodology was used, based on in-depth interviews with 52 children from these countries and educators from their support centres. Immigrant minors usually access the Internet via their smartphones rather than via computers. They have a very high rate of smartphone use and access the Internet over public Wi-Fi networks. However, they make little use of computers and tablets, the devices most closely associated with education and accessing information. Internet usage is fairly similar among immigrant and Spanish teens, although the former receive more support and mediation from their schools and institutions than from their parents. The Internet helps them to communicate with their families in their countries of origin. As one educator puts it, “they have gone from sending photos in letters to speaking to their families every day on Skype”. Some teens, particularly Maghrebis, sometimes suffer from hate messages on social networks.

scholarly journals WHICH OPTIONS FIT BEST? OPERATIONALIZING THE SOCIO-ECOLOGICAL NICHE CONCEPT

2016 ◽  
Vol 55 (S1) ◽  
pp. 169-190 ◽  
Author(s):  
KATRIEN DESCHEEMAEKER ◽  
ESTHER RONNER ◽  
MARY OLLENBURGER ◽  
ANGELINUS C. FRANKE ◽  
CHARLOTTE J. KLAPWIJK ◽  
...  
Keyword(s):  
Systems Analysis ◽  
Ecological Niche ◽  
Smallholder Farmers ◽  
Farming Systems ◽  
Sub Saharan Africa ◽  
Cultural Economic ◽  
Niche Concept ◽  
Sub Saharan ◽  
Farming Systems Analysis ◽  
On Farm

SUMMARYThe large diversity of farms and farming systems in sub-Saharan Africa calls for agricultural improvement options that are adapted to the context in which smallholder farmers operate. The socio-ecological niche concept incorporates the agro-ecological, socio-cultural, economic and institutional dimensions and the multiple levels of this context in order to identify which options fit best. In this paper, we illustrate how farming systems analysis, following the DEED cycle of Describe, Explain, Explore and Design, and embedding co-learning amongst researchers, farmers and other stakeholders, helps to operationalize the socio-ecological niche concept. Examples illustrate how farm typologies, detailed farm characterization and on-farm experimental work, in combination with modelling and participatory approaches inform the matching of options to the context at regional, village, farm and field level. Recommendation domains at these gradually finer levels form the basis for gradually more detailed baskets of options from which farmers and other stakeholders may choose, test and adjust to their specific needs. Tailored options identified through the DEED cycle proof to be more relevant, feasible and performant as compared to blanket recommendations in terms of both researcher and farmer-identified criteria. As part of DEED, on-farm experiments are particularly useful in revealing constraints and risks faced by farmers. We show that targeting options to the niches in which they perform best, helps to reduce this risk. Whereas the conclusions of our work about the potential for improving smallholders’ livelihoods are often sobering, farming systems analysis allows substantiating the limitations of technological options, thus highlighting the need for enabling policies and institutions that may improve the larger-scale context and increase the uptake potential of options.

Making the best of climatic variability: options for upgrading rainfed farming in water scarce regions

2004 ◽  
Vol 49 (7) ◽  
pp. 151-156 ◽  
Author(s):  
J. Rockström
Keyword(s):  
Soil Fertility ◽  
Water Scarcity ◽  
Social Impact ◽  
Climatic Variability ◽  
Sub Saharan Africa ◽  
Dry Spells ◽  
Rainfed Farming ◽  
Dry Spell ◽  
Sub Saharan ◽  
On Farm

Coping with climatic variability for livelihood security is part of everyday life for rural communities in semi-arid and dry sub-humid savannas. Water scarcity caused by rainfall fluctuations is common, causing meteorological droughts and dry spells. However, this paper indicates, based on experiences in sub-Saharan Africa and India, that the social impact on rural societies of climatically induced droughts is exaggerated. Instead, water scarcity causing food deficits is more often caused by management induced droughts and dry spells. A conceptual framework to distinguish between manageable and unmanageable droughts is presented. It is suggested that climatic droughts require focus on social resilience building instead of land and water resource management. Focus is then set on the manageable part of climatic variability, namely the almost annual occurrence of dry spells, short 2–4 week periods of no rainfall, affecting farmer yields. On-farm experiences in savannas of sub-Saharan Africa of water harvesting systems for dry spell mitigation are presented. It is shown that bridging dry spells combined with soil fertility management can double and even triple on-farm yield levels. Combined with innovative systems to ensure maximum plant water availability and water uptake capacity, through adoption of soil fertility improvement and conservation tillage systems, there is a clear opportunity to upgrade rainfed farming systems in vulnerable savanna environments, through appropriate local management of climatic variability.

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