Microbial carbon pump: additional considerations

The microbial carbon pump: from genes to ecosystems.

The majority of marine dissolved organic carbon (DOC) is resistant to biological degradation and thus can remain in the water column for thousands of years, constituting carbon sequestration in the ocean. To date the origin of such recalcitrant DOC (RDOC) is unclear. A recently proposed conceptual framework, the microbial carbon pump (MCP), emphasizes the microbial transformation of organic car...

HORIZONS Biological or microbial carbon pump? The role of phytoplankton stoichiometry in ocean carbon sequestration

Once fixed by photosynthesis carbon becomes part of the marine food web. The fate of this carbon has two possible outcomes, it may be respired and released back to the ocean and potentially to the atmosphere as CO2 or retained in the ocean interior and/or marine sediments for extended time scales. The most important biologically mediated processes responsible for long-term carbon storage in the...

Antidepressants in the postpartum period: additional considerations.

Sample sizes for usability studies: additional considerations.

Recently, Virzi (1992) presented data that support three claims regarding sample sizes for usability studies: (1) observing four or five participants will allow a usability practitioner to discover 80% of a product's usability problems, (2) observing additional participants will reveal fewer and fewer new usability problems, and (3) more severe usability problems are easier to detect with the f...

The Pill vs. the Sword: Additional Considerations; Comment on “The Pill Is Mightier Than the Sword”

In this paper, I present additional information for policy-makers and researchers to consider in response to the view proposed by Potts et al that “the pill is mightier than the sword.” I identify states with both high rates of terrorism and a youth bulge and discuss correlates of both these societal characteristics. The research examined supports the view that factors other than access to fami...