From the Editors’ Desk: Challenging Problems, Challenging Patients

Challenging problems in cocarcinogenesis.

The role of hormones as sensitizers in mammary carcinogenesis can be surmised on a priori grounds: (a) from general evidence of hormone involvement in the maturation of mammary tissue; (b) from differences in incidence of mammary tumors between the sexes; (c) from dietary influences on the incidence of mammary tumors, a high-fat diet affecting the hormonal status of the body (8); and (d) more s...

Challenging Problems in Rhinoplasty.

Rhinoplasty is the most common facial plastic procedure practiced today. Since thenose is the central andmost prominent part of the face, the reasons for the popularity of this operation should be obvious. However, the major part of the credit for the acceptance of this operation by the public is due to the pioneer, dedicated surgeons who have contributed a great number of technical innovations...

Musings from the Editors' Desk

Algorithms for Challenging Motif Problems

Pevzner and Sze(19) have introduced the Planted (l,d)-Motif Problem to find similar patterns (motifs) in sequences which represent the promoter regions of co-regulated genes, where l is the length of the motif and d is the maximum Hamming distance around the similar patterns. Many algorithms have been developed to solve this motif problem. However, these algorithms either have long running time...

Image processing: some challenging problems.

Image processing can be broadly defined as the manipulation of signals which are inherently multidimensional. The most common such signals are photographs and video sequences. The goals of processing or manipulation can be (i) compression for storage or transmission; (ii) enhancement or restoration; (iii) analysis, recognition, and understanding; or (iv) visualization for human observers. The u...