in this study, the substrate diffusion in an immobilized spherical cell-support aggregate is studied and effects of various parameters are investigated on substrates profile. analyses are performed by using of an analytical solution called the least square method (lsm) and results are compared with numerical solution. the effects of effective diffusion coefficient ( d e ), maximum specific grow...

Toll-like receptors (TLRs) are ancient microbial pattern recognition receptors highly conserved from Drosophila to humans. To investigate if subsets of human dendritic cell precursors (pre-DC), including monocytes (pre-DC1), plasmacytoid DC precursors (pre-DC2), and CD11c(+) immature DCs (imDCs) are developed to recognize different microbes or microbial antigens, we studied their TLR expression...

Soil microbial communities have the metabolic and genetic capability to adapt to changing environmental conditions on very short time scales. In this paper we combine biogeochemical and molecular approaches to reveal this potential, showing that microbial biomass can turn over on time scales of days to months in soil, resulting in a succession of microbial communities over the course of a year....

Heterotrophic microbes colonizing detritus obtain nitrogen (N) for growth by assimilating N from their substrate or immobilizing exogenous inorganic N. Microbial use of these two pools has different implications for N cycling and organic matter decomposition in the face of the global increase in biologically available N. We used sugar maple leaves labeled with 15N to differentiate between micro...

Microbial testing performed in support of pharmaceutical and biopharmaceutical production falls into three main categories: detection (qualitative), enumeration (quantitative), and characterization/identification. Traditional microbiological methods listed in the compendia and discussed by using the conventional growth-based techniques, which are labor intensive and time consuming. In general, ...

Cultivation-independent molecular phylogenetic techniques are now widely employed to examine environmental microbial diversity; however, the relationship between microbial community structure and ecosystem function is unclear. This review synthesizes cultivation-independent views of microbiological diversity with our current understanding of nutrient dynamics in alpine and arctic soils. Recentl...

Diversity is often associated with the functional stability of ecological communities from microbes to macroorganisms. Understanding how diversity responds to environmental perturbations and the consequences of this relationship for ecosystem function are thus central challenges in microbial ecology. Unimodal diversity-disturbance relationships, in which maximum diversity occurs at intermediate...

Subalpine grasslands are highly seasonal environments and likely subject to strong variability in nitrogen (N) dynamics. Plants and microbes typically compete for N acquisition during the growing season and particularly at plant peak biomass. During snowmelt, plants could potentially benefit from a decrease in competition by microbes, leading to greater plant N uptake associated with active gro...

Toranzos of NSF provided guidance and logistical support for the workshop. We thank Myrna Watanabe for help with report preparation. Executive Summary Introduction The National Science Foundation (NSF) Microbial Observatory (MO) and Life in Extreme Environments (LExEn) programs have fostered significant advances in microbial ecosystems research in a wide variety of natural environments. The inv...