RESUMEN
While Li-ion batteries are abundant in everyday life from smart phones to electric vehicles, there are a lack of educational resources that can explain their operation, particularly their rechargeable nature. It is also important that any such resource can be understood by a wide range of age groups and backgrounds. To this end, we describe how modified tower block games sets, such as Jenga, can be used to explain the operation of Li-ion batteries. The sets can also be utilized to explain more advanced topics such as battery degradation and challenges with charging these batteries at high rates. In order to make the resource more inclusive, we also illustrate modifications to prepare tactile tower block sets, so that the activity is also suitable for blind and partially sighted students. Feedback from a range of groups supports the conclusion that the tower block sets are a useful tool to explain Li-ion battery concepts.
RESUMEN
A gene encoding bovine prochymosin (PC) was fused to the coding sequence (phoA) for the Escherichia coli alkaline phosphatase (AP) signal peptide and expressed in E. coli under the control of the phoA promoter. Upon induction, an AP-PC fusion protein was produced which was neither processed nor exported into the periplasm. We investigated this lack of secretion by constructing a series of gene fusions in which different regions of the PC gene were inserted between the coding regions of the AP leader and mature protein. Analysis of the cellular location of the proteins encoded by these fusions revealed that a region of PC (between amino acids 6 and 29) prevented processing and secretion of an AP-PC fusion when inserted near to the AP signal peptide. In contrast, when this 'blocking sequence' was inserted elsewhere in AP the hybrid proteins were efficiently processed and translocation was initiated.