We prove that the class of 1324-avoiding permutations has exponential growth rate at most 13.74. To Richard Stanley, on the occasion of his seventieth birthday.

The ability of a virus to alter an expected immune response first received recognition over three-quarters of a century ago. At that time, Clements von Pirquet (1) observed that children who were tuberculin positive before contracting acute measles virus infection failed to mount specific skin responses to tuberculin during that virus infection. Later reports confirmed von Pirquet's observation...

Background and purpose: A likely explanation for the increase in lens fluorescence with aging and the acceleration of this process in patients with diabetes, is that lens proteins are altered by non-enzymatic glycosylation and the further steps of the Maillard reaction. Thus, the lens fluorescence intensity appears to represent a cumulative index of glycemia over the entire lifetime of the subj...