Atomic force microscopy (AFM) was used to study the structure of the staphylococcal alpha-hemolysin (alpha HL) oligomer formed in supported phospholipid bilayers. In contrast to the recent X-ray crystallographic demonstration of a heptameric stoichiometry for the oligomer formed in deoxycholate (DOC) micelles, the high-resolution unprocessed AFM images unequivocally revealed a hexamer in these ...

Phytoplankton growth and stoichiometry depend on the availability of multiple nutrients. We use a mathematical model of phytoplankton with flexible stoichiometry to explain patterns of phytoplankton composition in chemostat experiments and nutrient drawdown dynamics that are found in the field. Exponential growth and equilibrium represent two distinct phases, each amenable to mathematical analy...

This work presents thermoplastic analysis of FG rotating diskswith variable thickness and constant angular velocity. The solutions are obtained by variable material property (VMP) theory. In this theory, the domain is divided into some finite sub-domains in the radial direction, in which the properties are assumed to be constant and the form of the elastic response is used to solve elastic-plas...

data envelopment analysis (dea) is a non-parametric approach for performance analysis of decision making units (dmus) which uses a set of inputs to produce a set of outputs without the need to consider internal operations of each unit. in recent years, there have been various studies dealt with two-stage production systems, i.e. systems which consume some inputs in their first stage to produce ...

We present thermodynamic and empirical calculations for the iron-wüstite (IW) buffer applicable from 100 kPa to GPa 1000 3000 K. The calculation self-consistently accounts changing stoichiometry of iron-saturated wüstite as a function temperature pressure. In contrast some previous models calculating IW at high pressure, model incorporates thermodynamically valid representation free energy stoi...

Integrating microbial physiology and biomass stoichiometry opens far-reaching possibilities for linking microbial dynamics to ecosystem processes. For example, the growth-rate hypothesis (GRH) predicts positive correlations among growth rate, RNA content, and biomass phosphorus (P) content. Such relationships have been used to infer patterns of microbial activity, resource availability, and nut...