Biotechnology in the Fine-Chemicals Industry: Cyclic Amino Acids by Enantioselective Biocatalysis

Enantiomerically pure cyclic amino acids are of increasing interest for the life-science industry. To meet this demand, Lonza has developed biotransformation processes with emphasis on the integration of chemistry and biocatalysis for the production of homochiral proline, piperidine-2-carboxylic acid and piperazine-2-carboxylic acid, and valuable derivatives of these compounds. The processes are designed for use on industrial scale; they have been optimised with respect to availability and cost of starting materials and biocatalyst, productivity of the process and a feasible product isolation procedure. Because of the extraordinarily high enantioselectivity of the enzymes, the (R)- and the (S)-enantiomers of the unnatural cyclic amino acids, which are both of commercial interest, can be produced in a single reaction. The examples presented demonstrate the benefit from interdisciplinary research for the production of fine chemicals by the combination of chemistry and biotechnology

Diurnal variations in vegetation activity affecting shallow groundwater flow identified by microthermal measurements

Observations of summer microthermal temperature variations suggest, next to hydrological factors, a significant influence of plant activity on groundwater flow in fractured claystone materials. Variations in groundwater microtemperature were compared to variations in meteorological parameters and electrical potential of plants. With an increase in surface temperature, relative air humidity decreases and an increase in tree electrical potential, measured as the difference between the northern and the southern stem exposure (N–S), can be observed. This increase in electrical potential is concomitant with a change in groundwater temperature of approximately 2 mK. This relationship does not always occur. At high temperatures (+30° C) the decrease amounts to just 1 mK. This fact is related to the change in transpiration of plants, decreased or even suspended at high surface temperatures. A frequency analysis of all data showed a daily frequency of high magnitude in all parameters. Possibly changes in the macro weather situation events were observed in the results of atmospheric pressure, southern electric potential and groundwater temperature. The lag time between changes in electric potential and subsurface microtemperature changes amounts to 17 hours, possibly a result of the electrical potential difference between the northern and the southern exposure of the stem (N–S), and 5 hours, the result of the change in electrical potential difference between the southern and the northern stem exposure side (S–N). A comparison between potential changes and the computed change in gravity resulting from earth tidal effects showed that the correlation between the subsurface temperature variation with up to 2 mK and the change in surface temperature variation does not match directly. Other study shows that the impact of earth tides on subsurface microtemperature variation amounts to ca. 1mK. The effect of groundwater abstraction by mature vegetation is determined at the same range. Atmospheric tides can be correlated with the changes in north and south electric potentials

Numerical Analysis of Algorithms for Infinitesimal Associated and Non-Associated Elasto-Plasticity

The thesis studies nonlinear solution algorithms for problems in infinitesimal elastoplasticity and their numerical realization within a parallel computing framework. New algorithms like Active Set and Augmented Lagrangian methods are proposed and analyzed within a semismooth Newton setting. The analysis is often carried out in function space which results in stable algorithms. Large scale computer experiments demonstrate the efficiency of the new algorithms

Development of a numerical workflow based on μ-CT imaging for the determination of capillary pressure-saturation-specific interfacial area relationship in 2-phase flow pore-scale porous-media systems: A case study on Heletz sandstone

In this case study, we present the implementation of a finite element method (FEM)-based numerical pore-scale model that is able to track and quantify the propagating fluid–fluid interfacial area on highly complex micro-computed tomography (μ-CT)-obtained geometries. Special focus is drawn to the relationship between reservoir-specific capillary pressure (pc), wetting phase saturation (Sw) and interfacial area (awn). The basis of this approach is high-resolution μ-CT images representing the geometrical characteristics of a georeservoir sample. The successfully validated 2-phase flow model is based on the Navier–Stokes equations, including the surface tension force, in order to consider capillary effects for the computation of flow and the phase-field method for the emulation of a sharp fluid–fluid interface. In combination with specialized software packages, a complex high-resolution modelling domain can be obtained. A numerical workflow based on representative elementary volume (REV)-scale pore-size distributions is introduced. This workflow aims at the successive modification of model and model set-up for simulating, such as a type of 2-phase problem on asymmetric μ-CT-based model domains. The geometrical complexity is gradually increased, starting from idealized pore geometries until complex μ-CT-based pore network domains, whereas all domains represent geostatistics of the REV-scale core sample pore-size distribution. Finally, the model can be applied to a complex μ-CT-based model domain and the pc–Sw–awn relationship can be computed

Radion production in exclusive processes at CERN LHC

In the Randall-Sundrum (RS) scenario the compactification radius of the extra dimension is stabilized by the radion, which is a scalar field lighter than the graviton Kaluza-Klein states. It implies that the detection of the radion will be the first signature of the stabilized RS model. In this paper we study the exclusive production of the radion in electromagnetic and diffractive hadron - hadron collisions at the LHC. Our results demonstrate that the diffractive production of radion is dominant and should be feasible of study at CERN LHC.Comment: 6 pages, 3 figures, 1 tabl