Polysiloxanes terminated with one or more hydroxy functional carbamate groups are provided. The first and second barrier layers are formed to a combined thicknesses so that a Tunnelling Magnetoresistance versus voltage characteristic of the cell has a maximum at a non-zero bias voltage. Optionally, stomach acid may be captured and returned to the stomach. Specifically, when the gas sensor is installed in the exhaust pipe of the engine, the joint is located farther away from a heat source than the top end of the thread, thereby avoiding loosening of the joint or dislodgement of the cover from the housing. After that, the status of every interface cards is checked for confirming whether an error occurs or not. This approach is illustrated by recent findings that show that ferritin-H, an iron-binding protein that is present in cell nuclei, can repress the human -globin gene, the gene that is mutated in sickle cell disease.