The fires that commonly occur during this period are necessary for the germination of many shrub seeds and also serve to clear away dense ground cover, thus maintaining the shrubby growth form of the vegetation by preventing the spread of trees.
Effects on lung macrophages may be especially prominent, because they serve to clear foreign materials like ENMs and bacterial pathogens.
Inflammation interferes with the activity of bacteria and viruses, and serves to clear them from the body.
In data also presented at the AAN meeting, another group of researchers demonstrated that sleep might serve to clear certain "toxic" protein products that have been linked to the development of Alzheimer disease.
These authors suggested that transient reduction in RNA metabolism serves to clear the gene expression palate to allow new programmes of gene expression to be established.
Astrocyte processes at synapses also play essential roles in transmitter homeostasis by expressing high levels of transporters for neurotransmitters such as glutamate, GABA, and glycine that serve to clear the neurotransmitters from the synaptic space [ 205, 212].
It serves to clear land for shifting cultivation, to convert forests to agricultural and pastoral lands, and to remove dry vegetation in order to promote agricultural productivity and the growth of higher yield grasses.
