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The biotechnological exploitation of microorganisms enables the use of metabolism for the production of economically valuable substances, such as drugs or food. It is, thus, unsurprising that the investigation of microbial metabolism and its regulation has been an active research field for many decades. As a result, several theories and techniques were developed that allow for the prediction of metabolic fluxes and yields as biotechnologically relevant output parameters. One important approach is to derive macrochemical equations that describe the overall metabolic conversion of an organism and basically treat microbial metabolism as a black box. The opposite approach is to include all known metabolic reactions of an organism to assemble a genome-scale metabolic model. Interestingly, both approaches are rather successful at characterizing and predicting the expected product yield. Over the years, macrochemical equations especially have been extensively characterized in terms of their thermodynamic properties. However, a common challenge when characterizing microbial metabolism by a single equation is to split this equation into two, describing the two modes of metabolism, anabolism and catabolism. Here, we present strategies to systematically identify separate equations for anabolism and catabolism. Based on metabolic models, we systematically identify all theoretically possible catabolic routes and determine their thermodynamic efficiency. We then show how anabolic routes can be derived, and we use these to approximate biomass yield. Finally, we challenge the view of metabolism as a linear energy converter, in which the free energy gradient of catabolism drives the anabolic reactions. [ABSTRACT FROM AUTHOR]

This paper numerically simulates the vortex-induced vibrations of ocean current energy harvester with attached spinning cylinders by using the embedded iterative immersed boundary method.The variations of the hydrodynamic properties(the root-mean-square lift coefficient CL,rms,the mean and root-mean-square drag coefficient CD,mean and CD,rms,and the maximum non-dimensional vibration amplitude Ymax/D) with the energy harvest damping ratio ζharness,the non-dimensional spinning velocity α and azimuthal angle θ of the attached cylinders are investigated.Moreover,the variations of the maximum non-dimensional vibration amplitude Ymax/D with the combined parameter α/θ are further investigated.A set of formula is presented by using the curve fitting method.The variations of the coefficients in the formula with influencing parameters are discussed qualitatively. [ABSTRACT FROM AUTHOR]

The application of high-temperature superconducting (HTS) equipment faces challenges that thick current leads connecting superconducting devices with external power sources will generate huge thermal load loss and the difficulty in persistent current operation for a long period. In this work, we have proposed the mechanism of a novel mechanically operated HTS energy converter based on the electromagnetic coupling of the permanent magnet and the HTS coil. The proposed HTS energy converter can charge and discharge a closed superconducting coil without electrical contact, and convert mechanical energy to electromagnetic energy efficiently. However, its working mechanism is theoretically controversial, as it seems to violate Lenz's law. An analytical method based on the method of equivalent circuit is proposed to explain its working mechanism and replicate all experimental electrical behaviour of the HTS energy converter. Experimental results have verified the theoretical analysis. The proposed mechanically operated HTS energy converter is easily controllable, making it promising in various of applications, including superconducting magnetic energy storage (SMES), high field magnets, energy harvesting of urban rail transportation and electromagnetic propulsion. • An analytical model is proposed to explain the phenomenon seeming against Lenz's law. • A novel wireless HTS energy converter with promising applications is proposed. • Factors that could affect working performance of the proposed device are discussed. • Experiments were carried out to verify the proposed analytical model. [ABSTRACT FROM AUTHOR]