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Arising out of civil conflict, disease, birth defects, and traumatic accidents, many people in developing countries lack hands or fingers. Prosthetic hands can help give these people a sense of agency and increased ability to perform everyday tasks. Unfortunately, many prostheses are prohibitively expensive and often require frequent maintenance and repair. Therefore, they are financially and geographically inaccessible to most people living in developing countries. A 3D printed, opensource hand is one possible solution owing to its low cost and potential for customization. However, the hand must be appropriate for the environmental conditions and lifestyles found in developing countries. To characterize the functionality of the 3D printed hand, a series of daily task and object tests were carried out. While the prosthesis was able to successfully complete a number of tasks, it had difficulty with those that required intricate movements and with heavy objects.

A need exists for a long-term, minimally-invasive system to monitor blood analytes. For certain analytes, such as glucose in the case of diabetics, a continuous system would help reduce complications. Current methods suffer significant drawbacks, such as low patient compliance for the finger stick test or short lifetime (i.e., 3–7 days) and required calibrations for continuous glucose monitors. Red blood cells (RBCs) are potential biocompatible carriers of sensing assays for long-term monitoring. We demonstrate that RBCs can be loaded with an analyte-sensitive fluorescent dye. In the current study, FITC, a pH-sensitive fluorescent dye, is encapsulated within resealed red cell ghosts. Intracellular FITC reports on extracellular pH: fluorescence intensity increases as extracellular pH increases because the RBC rapidly equilibrates to the pH of the external environment through the chloride-bicarbonate exchanger. The resealed ghost sensors exhibit an excellent ability to reversibly track pH over the physiological pH range with a resolution down to 0.014 pH unit. Dye loading efficiency varies from 30% to 80%. Although complete loading is ideal, it is not necessary, as the fluorescence signal is an integration of all resealed ghosts within the excitation volume. The resealed ghosts could serve as a long-term (>1 to 2 months), continuous, circulating biosensor for the management of diseases, such as diabetes.

Concept selection tools have been heavily integrated into engineering design education in an effort to reduce the risks and uncertainties of early-phase design ideas and aid students in the decision-making process. However, little research has examined the utility of these tools in promoting creative ideas or their impact on student team decision making throughout the conceptual design process. To fill this research gap, the current study was designed to compare the impact of two concept selection tools, the concept selection matrix (CSM) and the tool for assessing semantic creativity (TASC) on the average quality (AQL) and average novelty (ANV) of ideas selected by student teams at several decision points throughout an 8-week project. The results of the study showed that the AQL increased significantly in the detailed design stage, while the ANV did not change. However, this change in idea quality was not significantly impacted by the concept selection tool used, suggesting other factors may impact student decision making and the development of creative ideas. Finally, student teams were found to select ideas ranked highly in concept selection tools only when these ideas met their expectations, indicating that cognitive biases may be significantly impeding decision making.