OBJECTIVES Clinical trials in humans in Germany-as in many other countries-must be approved by local research ethics committees (RECs). The current study has been designed to document and evaluate decisions of chairpersons of RECs in the problematic field of non-therapeutic research with minors. The authors' purpose was to examine whether non-therapeutic research was acceptable for chairpersons...

It is well known that on classes of graphs of bounded tree-width, every monadic second-order property is decidable in polynomial time. The converse is not true without further assumptions. It follows from the work of Robertson and Seymour, that if a class of graphs K has unbounded tree-width and is closed under minors, then K contains all planar graphs. But on planar graphs, three-colorability ...

Lawmakers, children’s advocacy groups and modern society at large recognize the importance of protecting the Internet privacy of minors (under 18 years of age). Online Social Networks, in particular, take precautions to prevent third parties from using their services to discover and profile minors. These precautions include banning young children from joining, not listing minors when searching ...

We generalize Gaeta’s Theorem to the family of determinantal schemes. In other words, we show that the schemes defined by minors of a fixed size of a matrix with polynomial entries belong to the same G-biliaison class of a complete intersection whenever they have maximal possible codimension, given the size of the matrix and of the minors that define them.

It is known that the list of excluded minors for the minor-closed class of graphs of path-width 6 3 numbers in the millions. However, if we restrict the class to 3-connected graphs of path-width 6 3, then we can characterize it by five excluded minors.

When the directed graph of an n–by–n matrix A does not contain a Hamilton cycle, we exhibit a formula for detA in terms of sums of products of proper principal minors of A. The set of minors involved depends upon the zero/nonzero pattern of A.

SUMMARY This is the first of two articles reviewing consent in those under age 18 (also referred to as ‘minors’ UK law). can be a complex issue clinical practice because law endows competent/capacitated minors with absolute right accept treatment, but limited refuse. article summarises recent cases refusal treatment minors. It uses them ask central questions: how do we, clinicians, think about ...

Nancy G. Kinnersley and Michael A. Langston has determined [3] the excluded minors for the class of graphs with path-width at most two. Here we give a simpler presentation of their result. This also leads us to a new characterization, and a linear time recognition algorithm for graphs width path-width at most two. 1 History and introduction Based on the seminal work of Seymour and Robertson [4]...