Girth (tack) slightly too small, a girth extender may be used. A girth extender attaches to the billets of the saddle and lengthens them, so that a shorter girth may be used. Most jumping saddles have three billets. This not only allows the rider a spare should one break, but can also provide an adjustment option. For horses on which the saddle sits nicely, neither slipping forward or back, the first and third billets should be used. On horses where the saddle slips back, the first and second billets should be used. The second and third should never be used together, as
Organ-on-a-chip it can facilitate cross-species extrapolation. Used in conjunction with PBPK models, the devices permit an estimation of effective concentrations that can be used for studies with animal models or predict the human response. In the development of multicompartment devices, representations of the human body such as those in used PBPK models can be used to guide the device design with regard to the arrangement of chambers and fluidic channel connections to augment the drug development process, resulting in increased success in clinical trials. Organ-on-a-chip An organ-on-a-chip (OOC) is a multi-channel 3-D microfluidic cell culture chip that simulates the activities, mechanics