The response of N2 fixation and [Formula: see text] uptake to environmental conditions and nutrient enrichment experiments in three western U.S. lake systems was studied (eutrophic Clear Lake; mesotrophic Walker Lake; oligotrophic Lake Tahoe). We tested the effect of additions of bioactive trace metals molybdenum as Mo(V) and iron (Fe) as well as phosphate (P), N2 fixation, [Formula: see text],...

The use of bicortical screws to fix metacarpal fractures has been suggested to provide no added biomechanical advantage over unicortical screw fixation. However, this was only demonstrated in static loading regimes, which may not be representative of biological conditions. The present study was done to determine whether similar outcomes are obtained when cyclic loading is applied. Transverse mi...

While we now know that N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N2 fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or do...

The exploitation of the soybe an [Glycine max (L.) Merr.] -Bradyrhizobium japonicum symbiosis in varied environments requires an understanding of factors that may affect fixed and soil N assimilation. Temperature affects both soybean maturity and N requirement, and soil N availability. Five soybean varieties belonging to four maturity groups (00, IV, VI, and VIII) and their respective nonnodula...

While we now know that N2 fixation is a significant source of new nitrogen (N) in the marine environment, little is known about the fate of this N (and associated C), despite the importance of diazotrophs to global carbon and nutrient cycles. Specifically, does N fixed during N2 fixation fuel autotrophic or heterotrophic growth and thus facilitate carbon (C) export from the euphotic zone, or do...

A physiological, unbalanced model is presented that explicitly describes growth of the marine cyanobacterium Trichodesmium sp. at the expense of N(2) (diazotrophy). The model involves the dynamics of intracellular reserves of carbon and nitrogen and allows the uncoupling of the metabolism of these elements. The results show the transient dynamics of N(2) fixation when combined nitrogen (NO(3)(-...

Biological nitrogen fixation (BNF) is vital to the terrestrial nitrogen (N) budget, balancing N losses from denitrification and providing N for organism growth and maintenance. Limited information exists, however, to verify the importance of BNF by actinorhizal shrubs in moistureand nutrient-limited forests of the interior west. A series of studies are presented that evaluate BNF by actinorhiza...

Res. 2011;26(3):553-560. 32. Perren SM. Physical and biological aspects of fracture healing with special reference to internal fixation. Clin Orthop Relat Res. 1979;(138):175-196. 33. Perren SM. Evolution of the internal fixation of long bone fractures. The scientific basis of biological internal fixation: choosing a new balance between stability and biology. J Bone Joint Surg Br. 2002;84(8):10...

Biological nitrogen (N2) fixation is the primary input of new nitrogen (N) to marine systems, and is important in meeting the N demands of primary producers. In this study, we determined whether restoration of the eelgrass Zostera marina L. in a shallow coastal bay facilitated increasing rates of N2 fixation as the meadows aged. Rates of N2 fixation were measured in a system that had been devoi...