A Guide to Scaling Resource Recovery & Reuse (RRR) Business Innovations in Africa and Asia

Domestic waste is a continuously increasing urbanization challenge. Over the last decade, researchers with the International Water Management Institute (IWMI) have developed, tested and implemented (e.g. as PPP) a variety of RRR technologies and business models that simultaneously reduce the waste burden and support the return of resources like crop nutrients, biosolids and reclaimed water to agricultural production. The review compared over 20 scaling models and tools to identify those which best support the RRR innovations

Development and Evaluation of a Low-Cost Probe-Type Instrument to Measure the Equilibrium Moisture Content of Grain

Storage of grain in bags is common in Africa, Asia, and many other less developed countries making a bag probing method well-suited for moisture content (MC) measurement. A low-cost meter was developed under a USAID project to reduce post-harvest loss (PHL). The meter, referred to as the PHL meter, measures the MC of maize and other grains based on relative humidity (RH) and temperature (T) measurements obtained by a small digital sensor located in the tip of a tubular probe that can be inserted into bags of grain or other grain bulks. Measurements are used by equilibrium moisture content (EMC) equations programmed into the meter to predict MC. A handheld reader connected to the probe provides a user interface. The PHL moisture meter was evaluated based on laboratory studies in the United States and field studies in Ghana. Meter readings from field studies were compared to two commercial meters, a John Deere Chek-Plus-SW08120 grain moisture tester and a DICKEY-john GAC® 2100 Agri meter. The John Deere portable moisture meter is a low-cost meter by developed country standards (~US$250, 2016 price); the GAC 2100 bench-top moisture meter is an approved moisturetester by the Grain Inspection, Packers and Stockyards Administration (GIPSA) and has been a highly regarded and used electronic meter. Laboratory studies indicated that the PHL meter may require up to 6 min to take a measurement because of the time required by the probe tip and sensor to equilibrate to grain conditions. Methods to reduce the measurement time by measuring temporal equilibration rates were developed. These can be programmed into the reader to shorten measurement time for many conditions. The accuracy of the PHL moisture meter was comparable to the GAC 2100 moisture meter for maize below 15% MCwb. Average differences showed a positive offset of 0.45% for the PHL meter relative to the GAC 2100. The PHL meter provided an effective tool to probe bulk grain and bags

Genome-wide computational analysis reveals cardiomyocyte-specific transcriptional cis-regulatory motifs that enable efficient cardiac gene therapy

Gene therapy is a promising emerging therapeutic modality for the treatment of cardiovascular diseases and hereditary diseases that afflict the heart. Hence, there is a need to develop robust cardiac-specific expression modules that allow for stable expression of the gene of interest in cardiomyocytes. We therefore explored a new approach based on a genome-wide bioinformatics strategy that revealed novel cardiac-specific cis-acting regulatory modules (CS-CRMs). These transcriptional modules contained evolutionary-conserved clusters of putative transcription factor binding sites that correspond to a "molecular signature" associated with robust gene expression in the heart. We then validated these CS-CRMs in vivo using an adeno-associated viral vector serotype 9 that drives a reporter gene from a quintessential cardiac-specific a-myosin heavy chain promoter. Most de novo designed CS-CRMs resulted in a > 10-fold increase in cardiac gene - expression. The most robust CRMs enhanced cardiac-specific transcription 70- to 100-fold. Expression was sustained and restricted to cardiomyocytes. We then combined the most potent CS-CRM4 with a synthetic heart and muscle-specific promoter (SPc5-12) and obtained a significant 20-fold increase in cardiac gene expression compared to the cytomegalovirus promoter. This study underscores the potential of rational vector design to improve the robustness of cardiac gene therapy

Secondary bacterial infections of buruli ulcer lesions before and after chemotherapy with streptomycin and rifampicin

Buruli ulcer (BU), caused by Mycobacterium ulcerans is a chronic necrotizing skin disease. It usually starts with a subcutaneous nodule or plaque containing large clusters of extracellular acid-fast bacilli. Surrounding tissue is destroyed by the cytotoxic macrolide toxin mycolactone produced by microcolonies of M. ulcerans. Skin covering the destroyed subcutaneous fat and soft tissue may eventually break down leading to the formation of large ulcers that progress, if untreated, over months and years. Here we have analyzed the bacterial flora of BU lesions of three different groups of patients before, during and after daily treatment with streptomycin and rifampicin for eight weeks (SR8) and determined drug resistance of the bacteria isolated from the lesions. Before SR8 treatment, more than 60% of the examined BU lesions were infected with other bacteria, with Staphylococcus aureus and Pseudomonas aeruginosa being the most prominent ones. During treatment, 65% of all lesions were still infected, mainly with P. aeruginosa. After completion of SR8 treatment, still more than 75% of lesions clinically suspected to be infected were microbiologically confirmed as infected, mainly with P. aeruginosa or Proteus miriabilis. Drug susceptibility tests revealed especially for S. aureus a high frequency of resistance to the first line drugs used in Ghana. Our results show that secondary infection of BU lesions is common. This could lead to delayed healing and should therefore be further investigated

Nutrient recycling from organic wastes through viable business models in peri-urban areas in Sub-Saharan Africa

A major challenge of urbanisation, for relevant decision makers, is the provision of sufficient food and water for the emerging mega-cities and appropriate peri-urban sanitation management. This paper focuses on the results of a project carried out by International Water Management Institute (IWMI) in three major cities in Ghana. The project was designed to provide decision support for nutrient recycling from organic waste in peri-urban areas, through waste composting or co-composting with nightsoil. Experiences of existing compost stations from Nigeria, Benin, Mali, Burkina Faso and Togo were taken into consideration to formulate the research framework. Apart from the technical aspect, the study looked at actual waste supply and its quality, a quantification of the compost demand as well as economic viability of different scenarios and legal implications. The analysis showed that from the city perspective cost savings are only possible if large volumes of waste can be composted to reduce waste transport costs while compost sale (and agricultural use) is not a necessity from the perspective of cost savings. In fact, despite much interest the farmers’ willingness to pay remained limited at the reservation price of US$5 per 50 kg bag. As this includes transport costs peri-urban areas will be those benefiting most from composting projects. Closing the rural-urban nutrient cycle appears unrealistic given the increasing transport distance; at least as long as smallholder farmers are targeted. However, the consideration of alternative customer segments and implementation of innovative business models could help in reaching different scales

Financial and economic aspects of urban vegetable farming

This chapter explores some of the financial and economic aspects of urban and peri-urban agriculture in Ghana. Cost-benefit analysis comparisons were made of farm finances of common rural, peri-urban and urban farming systems. Substudies also tried to quantify benefits for society and to cost externalities related to soil nutrient depletion, pesticide use and urban malaria