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Iodo-Gilman reagents Me 2 -CuLi´LiI, Bu 2 CuLi´LiI, and BuThCuLi´LiI and cyano-Gilman reagents (ne  e ªhigher order cyanocupratesº Me 2 CuLi´LiCN, Bu 2 CuLi´LiCN, and BuThCuLi´LiCN react with 2-cyclohexenone at various rates, which depend upon the R groups (Me, Bu, Th thienyl), Li salt (LiI vs. LiCN), solvent (ether vs. THF), and amount of trimethylsilyl chloride (TMSCl) additive. The effect of the Li salt (CuI vs. CuCN precursor) is less than that of solvent or TMSCl. The butylcuprate-iodocyclohexane reaction has also been examined as a function of Li salt, solvent, and TMSCl additive, and similar effects are observed. The reactivity matrix R with elements r i,j is a convenient way to store and present a large amount of relative reactivity data. Entry r i,j is the ratio of the rate with reagent i to the rate with reagent j, which we approximate by using yields measured after a short time (4 s). The logarithmic reactivity profile (LRP) provides an efficient means for determining yields under conditions where such comparisons are valid. The results of a large number of 4-point LRPs and related reactions are tabulated and analyzed to provide a clearer picture of organocuprate reactivity.

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Cell-free DNA analysis is becoming adopted for first line aneuploidy screening, however for most healthcare programs, cost and workflow complexity is limiting adoption of the test. We report a novel cost effective method, the Vanadis NIPT assay, designed for high precision digitally-enabled measurement of chromosomal aneuploidies in maternal plasma. Reducing NIPT assay complexity is achieved by using novel molecular probe technology that specifically label target chromosomes combined with a new readout format using a nanofilter to enrich single molecules for imaging and counting without DNA amplification, microarrays or sequencing. The primary objective of this study was to assess the Vanadis NIPT assay with respect to analytical precision and clinical feasibility. Analysis of reference DNA samples indicate that samples which are challenging to analyze with low fetal-fraction can be readily detected with a limit of detection determined at <2% fetal-fraction. In total of 286 clinical samples were analysed and 30 out of 30 pregnancies affected by trisomy 21 were classified correctly. This method has the potential to make cost effective NIPT more widely available with more women benefiting from superior detection and false positive rates.

Large plastic deformation in sheets made of dual phase steel DP800 is studied experimentally and numerically. Shear testing is applied to obtain large plastic strains in sheet metals without strain localisation. In the experiments, full-field displacement measurements are carried out by means of digital image correlation, and based on these measurements the strain field of the deformed specimen is calculated. In the numerical analyses, an elastoplastic constitutive model with isotropic hardening and the CockcroftLatham fracture criterion is adopted to predict the observed behaviour. The strain hardening parameters are obtained from a standard uniaxial tensile test for small and moderate strains, while the shear test is used to determine the strain hardening for large strains and to calibrate the fracture criterion. Finite Element (FE) calculations with shell and brick elements are performed using the non-linear FE code LS-DYNA. The local strains in the shear zone and the nominal shear stress-elongation characteristics obtained by experiments and FE simulations are compared, and, in general, good agreement is obtained. It is demonstrated how the strain hardening at large strains and the CockcroftLatham fracture criterion can be calibrated from the in-plane shear test with the aid of non-linear FE analyses.