(Cont.) A kinematic coupling that uses planar flexures was designed, constructed and tested. This coupling showed similar repeatability to a rigid coupling used as a control when the ball-and-flat contacts of both were free of wear; however, the flexure-based coupling performed much better than the control coupling after the contacts had been roughened by material failures resulting from repeated loading.

In the first edition of The Enzymes of Biological Membranes, published in four volumes in 1976, we collected the mass of widely scattered information on membrane-linked enzymes and metabolic processes up to about 1975. This was a period of transition from the romantic phase of membrane biochemistry, preoccupied with conceptual developments and the general properties of membranes, to an era of mounting interest in the specific properties of membrane-linked enzymes analyzed from the viewpoints of modem enzymology. The level of sophistication in various areas of membrane research varied widely; the structures of cytochrome c and cytochrome b5 were known to atomic detail, while the majority of membrane-linked enzymes had not even been isolated. In the intervening eight years our knowledge of membrane-linked enzymes ex panded beyond the wildest expectations. The purpose of the second edition of The Enzymes of Biological Membranes is to record these developments. The first volume describes the physical and chemical techniques used in the analysis of the structure and dynamics of biological membranes. In the second volume the enzymes and met abolic systems that participate in the biosynthesis of cell and membrane components are discussed. The third and fourth volumes review recent developments in active transport, oxidative phosphorylation and photosynthesis.

Drosophila melanogaster (fruit fly) is a highly versatile model with a genetic legacy of more than a century. It provides powerful genetic, cellular, biochemical and molecular biology tools to address many questions extending from basic biology to human diseases. One of the most important questions in biology is how a multi-cellular organism develops from a single-celled embryo. The discovery of the genes responsible for pattern formation has helped refine this question and has led to other questions, such as the role of various genetic and cell biological pathways in regulating the process of pattern formation and growth during organogenesis. The Drosophila eye model has been extensively used to study molecular genetic mechanisms involved in patterning and growth. Since the genetic machinery involved in the Drosophila eye is similar to humans, it has been used to model human diseases and homology to eyes in other taxa. This updated second edition covers current progress in the study of molecular genetic mechanisms of pattern formation, mutations in axial patterning, genetic regulation of growth, and more using the Drosophila eye as a model.