lates each of these developmental processes. *Department of Genetics One answer is that there are multiple Egfr ligands that Howard Hughes Medical Institute activate the RTK in a tissue-specific manner. CharacterHarvard Medical School ization of mutants that exhibit only a subset of the Egfr Boston, Massachusetts 02115 mutant phenotypes led to the identification of three can†Pediatric Surgical ...

A medical institution possesses both public and private inter­ ests. However, recently, the public side of things has been em­ phasized because medical practice can involve invading the hu­ man body for treatment. As a result of this emphasis on public interests, medical law stipulates symbolic regulations on a hos­ pital's duty to prevent infections and the duty of medical per­ sonnel to provi...

We exhibit a polynomial time computable plane curve Γ that has finite length, does not intersect itself, and is smooth except at one endpoint, but has the following property. For every computable parametrization f of Γ and every positive integer n, there is some positive-length subcurve of Γ that f retraces at least n times. In contrast, every computable curve of finite length that does not int...

Human computation is the technique of performing a computational process by outsourcing some of the difficult-toautomate steps to humans. In the social and behavioral sciences, when using humans as measuring instruments, reproducibility guides the design and evaluation of experiments. We argue that human computation has similar properties, and that the results of human computation must be repro...