Lump kidney

Fig. 4.5a-f. Six types of crossed renal ectopia with fusion a unilateral fused kidney, superior ectopia b sigmoid or S-shaped kidney c lump kidney d L-shaped kidney e disk kidney f unilateral fused kidney, inferior ectopia... 

Ordinarily, small amounts of calcium ions and oxalate ions are excreted in a person s urine, along with tiny crystals of calcium oxalate that may form. In exceptional cases, however, the crystals can lump together to form kidney stones. Kidney stones can block the tubes leading from the kidneys to the urethra. Passing a kidney stone may be extremely painful, and, in some cases, surgery may be required. 

The chapter itself is organized as follows. In Section 11.1, we discuss experiments in which data can be organized using mass transfer coefficients. Section 11.2 describes blood oxygenators and artificial kidneys, mass transfer devices whose geometry is exactly known. Section 11.3 discusses the role of mass transfer in pharmacokinetics, where the system s geometry is unknown, lumped into other parameters which may include the mass transfer coefficient. Thus the chapter provides an introduction for life scientists to important engineering ideas. 

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