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Effective interaction potentials suitable for Cu/δ-Ni 2 Si and Cu/β-Ni 3 Si are developed. We optimise the potential parameters of an embedded atom method potential to reproduce forces, energies, and stresses obtained from ab initio calculations. Details of the potential generation are given, and its validation is demonstrated. The potentials are used in molecular dynamics simulations of shear tests to study the interactions of edge dislocations with coherent δ-Ni 2 Si and β-Ni 3 Si precipitates embedded in a copper matrix. In spite of significantly different crystallographic structures of copper and δ-Ni 2 Si which usually result in circumvention of dislocations, we also observed cutting processes in our simulations. Dislocations cut for a specific orientation of the δ-Ni 2 Si precipitate and in some cases where dislocation loops originating from previous circumvention processes are present in the glide plane. It is found that β-Ni 3 Si precipitates have a similar effect on precipitation strengthening as δ-Ni 2 Si. Dislocations usually cut β-Ni 3 Si but increased coherency strain can lead to circumvention processes.

Here, we describe the production of stable isotope-labeled human immunoglobulin G1 ([ 13 C]-hIgG1) using [ 13 C]-L-lysine/arginine-labeled hIgG1. The fermentation process was run in shake flasks containing labeled arginine and lysinethat were incorporated into the produced recombinant hIgG1. The [ 13 C]-hIgG1 was purified, and label incorporation was determined to be >99% at all lysine and arginine moieties. Sequence coverage was confirmed by peptide mapping. [ 13 C]-hIgG1 was then used as an internal standard (IS) for the development of a liquid chromatography-tandem mass spectrometry method applicable to the quantitative analysis of all human types of hIgG1 in rat serum. Four conserved peptides, namely, GPSVFPLAPSSK, TTPPVLDSDGSFFLYSK, VVSVLTVLHQDWLNGK, and FNWYVDGVEVHNAK, originating from different parts of the fraction crystallizable region of hIgG1, were used for quantitation of hIgG1 in rat serum. The calibration curves with a coefficient of determination (r 2 ) between 0.9950 and 0.9962 resulting from the peak area ratio of each peptide to its respective labeled IS were reproducible. A mean bias within ±20.0% of the nominal values and a precision of ≤20.0 % were obtained for the calibration standards and quality control samples for each peptide. [ 13 C]-hIgG1 was shown as a suitable IS for quantitative hIgG1 analysis in preclinical species by LC-MS/MS., (Copyright © 2016 John Wiley & Sons, Ltd.)