An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles.

New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test's ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence. New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact

The recovery of the non-diagonal dail in a tiled triangular matrix ring.

NatuurwetenskappeWiskundePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]

Numerical simulation of conductive particle behaviour at the surface of a plate electrode affected by a dc corona field

International audienc

Isomorphisms between Morita context rings

Let (R, S, RM S, SN R,f,g) be a general Morita context, and let, be the ring associated with this context. Similarly, let, be another Morita context ring. We study the set Iso(T, T′) of ring isomorphisms from T to T′. Our interest in this problem is motivated by: (i) the problem to determine the automorphism group of the ring T, and (ii) the recovery of the non-diagonal tiles problem for this type of generalized matrix rings. We introduce two classes of isomorphisms from T to T′, the disjoint union of which is denoted by Iso 0(T, T′). We describe Iso 0(T, T′) by using the ℤ-graded ring structure of T and T′. Our main result characterizes Iso 0(T, T′) as the set consisting of all semigraded isomorphisms and all anti-semigraded isomorphisms from T to T′, provided that the rings R′ and S′ are indecomposable and at least one of M′ and N′ is nonzero; in particular, Iso 0(T, T′) contains all graded isomorphisms and all anti-graded isomorphisms from T to T′. We also present a situation where Iso 0(T, T′) = Iso(T, T′). This is in the case where R, S, R′ and S′ are rings having only trivial idempotents and all the Morita maps are zero. In particular, this shows that the group of automorphisms of T is completely determined. © 2012 Copyright Taylor and Francis Group, LLC

Factors that influence the surface potential decay on a thin film of polyethylene erephtalate

International audienc

Isomorphism of generalized triangular matrix-rings and recovery of tiles.

NatuurwetenskappeWiskundePlease help us populate SUNScholar with the post print version of this article. It can be e-mailed to: [email protected]