Cardiac Electrophysiology Procedures, Known Unknowns, and Unknown Unknowns

Sepsis-related stress response: known knowns, known unknowns, and unknown unknowns

The hypothalamic-pituitary-adrenal (HPA) axis response in sepsis remains to be elucidated. Apart from corticotropin-releasing hormone, adrenocorticotropic hormone, and cortisol, many other neuroendocrine factors participate in the regulation of HPA stress response. The HPA response to acute and chronic illness exerts a biphasic profile. Tissue corticosteroid resistance may also play an importan...

Known knowns, known unknowns, and unknown unknowns: can systems medicine provide a new approach to sepsis?

Known knowns, known unknowns, unknown unknowns and the propagation of scientific enquiry.

In February 2002, Donald Rumsfeld, the then US Secretary of State for Defence, stated at a Defence Department briefing: ‘There are known knowns. There are things we know that we know. There are known unknowns. That is to say, there are things that we now know we don’t know. But there are also unknown unknowns. There are things we do not know we don’t know.’ As a result, he was almost universall...

Known knowns, known unknowns, unknown unknowns and unknown knowns in DNA barcoding: a comment on Dowton et al.

RUPERT A. COLLINS1∗ AND ROBERT H. CRUICKSHANK2 1Laboratório de Evolução e Genética Animal, Departamento de Biologia, Universidade Federal do Amazonas, Av. Rodrigo Otávio, Manaus, Amazonas, Brazil and 2Department of Ecology, Faculty of Agriculture and Life Sciences, Lincoln University, Lincoln 7647, Canterbury, New Zealand ∗Correspondence to be sent to: Departamento de Biologia, Universidade Fed...

Known unknowns, unknown unknowns and information flow: new concepts in decentralized control

We introduce and analyze a model for decentralized control. The model is broad enough to include problems such as formation control, decentralization of the power grid and flocking. The objective of this paper is twofold. First, we show how the issue of decentralization goes beyond having agents know only part of the state of the system. In fact, we argue that a complete theory of decentralizat...