We based the study on the concept that composite scaffold materials, especially when combined with inorganic materials, are more suited to the mechanical and physiological demands of the host tissue than individual scaffold materials.
In order to maintain life, the regenerating liver must still support, even if partially, the metabolic demands of the host and provide for some liver synthetic function.
In these, the cyanobacterium has taken on a new physiological role, i.e. to fulfill the full nitrogen demands of the host via their enhanced nitrogen-fixing capacity [7].
One reason may be attributed to the immunological demands of the host at various sites [ 14].
However, what is true for virus infections, whether in compatible or incompatible interactions, is the increase in nutrient demands of the host as well as the cellular demands of mounting a defence response.
Depending on the relative demands of the host and the parasite for the limiting nutrient, intensified resource competition under nutrient limitation can either reduce the parasite's effect on the host or further reduce the fitness of the nutrient-limited host.
"Quality starvation" of hosts would be expected to increase the strength of competition for limiting elements between hosts and parasites, and the net outcome of this enhanced competition would depend on the demands of the host and the parasite for the limiting nutrient [ 12].
A commensal fungus frequently colonizing human mucosal surfaces, C. albicans has long been adapted to the human host and has evolved because of the specific demands of the human host environment.
This striking similarity between completely independent examples of mutualistic symbiosis suggests that increased ploidy of symbionts has been selected as a consequence of a symbiotic lifestyle, possibly because of increased demands from the host on productivity of the symbionts and relaxation of the selective constraints found in non-mutualistic relatives.
An event of this magnitude and cost, so demanding on the resources of the host nation, was unimaginable in Africa until now.
