Patients with Complex Chronic Diseases: Perspectives on Supporting Self-Management

A Complex Chronic Disease (CCD) is a condition involving multiple morbidities that requires the attention of multiple health care providers or facilities and possibly community (home)-based care. A patient with CCD presents to the health care system with unique needs, disabilities, or functional limitations. The literature on how to best support self-management efforts in those with CCD is lacking. With this paper, the authors present the case of an individual with diabetes and end-stage renal disease who is having difficulty with self-management. The case is discussed in terms of intervention effectiveness in the areas of prevention, addiction, and self-management of single diseases. Implications for research are discussed

Geochemical Evidence for Suppression of Pelagic Marine Productivity at the Cretaceous/Tertiary Boundary

The normal, biologically productive ocean is characterized by a gradient of the 13C /12C ratio from surface to deep waters. Here we present stable isotope data from planktonic and benthic microfossils across the Cretaceous/Tertiary boundary in the North pacific, which reveal a rapid and complete breakdown in this biologically mediated gradient. The fluxes of barium (a proxy for organic carbon) and CaCO, also decrease significantly at the time of the major marine plankton extinctions. The implied substantial reduction in oceanic primary productivity persisted for ~0.5 Myr before the carbon isotope gradient was gradually re-established. In addition, the stable isotope and preservational data indicate that environmental change, including cooling, began at least 200 kyr before the Cretaceous/Tertiary boundary, and a peak warming of ~3 °C occurred 600 kyr after the boundary event

Isotopic constraints on carbon exchange between deep ocean sediments and sea water

THE vast reservoirs of organic carbon in marine sediments1–3 have the potential to influence the properties of organic matter in the overlying water column. For example, it has been suggested that marine sediments are a possible source of the old, refractory dissolved organic carbon (DOC) found in deep water3–4. Natural radiocarbon and stable carbon isotope ratios (Δ14C and δ13C) can be used to constrain the role of sediments in the ocean carbon cycle5–8. Here we report the distributions of Δ14C and δ13C associated with dissolved organic and inorganic carbon in sediment pore water, together with those of the particulate sedimentary organic carbon, from two geochemically distinct marine environments. Concentration gradients of dissolved organic and inorganic carbon across the sediment–water interface imply significant diffusive fluxes of these solutes from the sediment to the water column. But the DOC fraction in the sediments is greatly enriched in 14C compared with that in the overlying sea water (by as much as 370%), indicating that the DOC supplied by sediments to ocean waters must be relatively young, and that its remnant ages in the water column itself. © 2015 Nature Publisher Group