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George Whitesides has developed a prototype for paper "chip" technology that could be used in the developing world to cheaply diagnose deadly diseases such as HIV, malaria, tuberculosis, hepatitis and gastroenteritis. The first products will be available in about a year, he said. His efforts, which find their inspiration from the simple designs of comic books and computer chips, are surprisingly low-tech and cheap. Patients put a drop of blood on one side of the slip of paper, and on the other appears a colorful pattern in the shape of a tree, which tells medical professionals whether the person is infected with certain diseases. Water-repellent comic-book ink saturates several layers of paper, he said. The ink funnels a patient's blood into tree-like channels, where several layers of treated paper react with the blood to create diagnostic colors. It's not entirely unlike a home pregnancy test, Whitesides said, but the chips are much smaller and cheaper, and they test for multiple diseases at once. They also show how severely a person is infected rather than producing only a positive-negative reading.

Solar-powered drip irrigation enhances food security in the Sudano–Sahel documents a field research project which found that: "solar-powered drip irrigation significantly augments both household income and nutritional intake, particularly during the dry season, and is cost effective compared to alternative technologies" Over the decades, irrigation has been shown to greatly increase agricultural productivity. Drip irrigation is spreading rapidly in Africa, with significant benefits. "Drip irrigation delivers water (and fertilizer) directly to the roots of plants, thereby improving soil moisture conditions; in some studies, this has resulted in yield gains of up to 100%, water savings of up to 40–80%, and associated fertilizer, pesticide, and labor savings over conventional irrigation systems" The solar-powered systems, however, look to offer the potential for even better results. From the study on impacts of PVDI systems it was reported: "The women’s agricultural group members utilizing the PVDI systems became strong net producers in vegetables with extra income earned from sales, significantly increasing their purchases of staples, pulses, and protein during the dry season, and oil during the rainy season. Finally, survey respondents were asked how frequently they were unable to meet their household food needs. Based on the frequency and most recent incident, households were assigned a food insecurity score ranging from zero (no problems during the previous year) to one (perpetually unable to meet food needs). This score changed significantly for project beneficiaries, as they were 17% less likely to feel chronically food-insecure. In short, the PVDI systems had a remarkable effect on both year-round and seasonal food access."