Sustainably feeding the world's growing population is a challenge, and closing yield gaps (that is, differences between farmers' yields and what are attainable for a given region) is a vital strategy to address this challenge. The magnitude of yield gaps is particularly large in developing countries where smallholder farming dominates the agricultural landscape. Many factors and constraints interact to limit yields, and progress in problem-solving to bring about changes at the ground level is rare. Here we present an innovative approach for enabling smallholders to achieve yield and economic gains sustainably via the Science and Technology Backyard (STB) platform. STB involves agricultural scientists living in villages among farmers, advancing participatory innovation and technology transfer, and garnering public and private support. We identified multifaceted yield-limiting factors involving agronomic, infrastructural, and socioeconomic conditions. When these limitations and farmers' concerns were addressed, the farmers adopted recommended management practices, thereby improving production outcomes. In one region in China, the five-year average yield increased from 67.9% of the attainable level to 97.0% among 71 leading farmers, and from 62.8% to 79.6% countywide (93,074 households); this was accompanied by resource and economic benefits.

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Self-piercing riveting (SPR) has become an important alternative joining technique for the automotive applications of aluminum sheets. Most existing SPR machines use electrical motors to drive a rivet into the sheets. A significant amount of research has been conducted to improve an SPR joint’s strength by increasing the mechanical interlock. In this paper, a new process is presented using gunpowder to drive the riveting process. A joint formed using the new process has different geometric characteristics from one created using a conventional system. The tensile-shear, cross-tension, fatigue, and impact performances of self-piercing riveted joints using the new device are compared to those of spot-welded joints on aluminum sheets. The experiment has proven that the new SPR joints have provided a similar or higher strength than resistance spot welds.

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