Norcoclaurine synthases (NCS), catalyzing a Pictet-Spengler reaction in plants as one of the first enzymes in the biosynthetic benzylisoquinoline pathway, are investigated for biocatalytic transformations. The library of NCS available is extended by two novel NCSs from Argemone mexicana (AmNCS1, AmNCS2) and one new NCS from Corydalis saxicola (CsNCS); furthermore, it is shown that the NCS from Papaver bracteatum (PbNCS) is a highly productive catalyst leading to the isoquinoline product with up to >99% e.e. Under certain conditions lyophilized whole Escherichia coli cells containing the various overexpressed NCS turned out to be suitable catalysts. The reaction using dopamine as substrate bears several challenges such as the spontaneous nonstereoselective background reaction and side reactions. The PbNCS enzyme is successfully immobilized on various carriers whereby EziG3 proved to be the best suited for biotransformations. Dopamine showed limited stability in solution resulting in the coating of the catalyst over time, which could be solved by the addition of ascorbic acid (e.g., 1 mg ml À1 ) as antioxidant.

We devise a framework based on the generalized contact formalism that combines the nuclear shell model and quantum Monte Carlo methods and compute the neutrinoless double-beta decay of experimentally relevant nuclei, including 76 Ge, 130 Te, and 136 Xe. In light nuclei, we validate our nuclear matrix element calculations by comparing against accurate variational Monte Carlo results. Due to additional correlations captured by quantum Monte Carlo and introduced within the generalized contact formalism, in heavier systems, we obtain long-range nuclear matrix elements that are about 30% smaller than previous shell-model results. We also evaluate the recently recognized short-range nuclear matrix element estimating its coupling by the charge-independence-breaking term of the Argonne v18 potential used in the Monte Carlo calculations. Our results indicate an enhancement of the total nuclear matrix element by around 30%.

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Appropriate use of HITH leads to greater patient and caregiver satisfaction, efficient in-hospital bed use, and financial efficiencies. Patients receiving intravenous antibiotics, wound care, parenteral nutrition, or transfusions do not always need to be in the hospital.

We calculate the nuclear matrix element for the two-neutrino ββ decay of 136 Xe into the first excited 0 + state of 136 Ba. We use different many-body methods: the quasiparticle random-phase approximation (QRPA) framework, the nuclear shell model, the interacting boson model (IBM-2), and an effective field theory (EFT) for β and ββ decays. While the QRPA suggests a decay rate at the edge of current experimental limits, the shell model points to a half-life about two orders of magnitude longer. The predictions of the IBM-2 and the EFT lie in between, and the latter provides systematic uncertainties at leading order. An analysis of the running sum of the nuclear matrix element indicates that subtle cancellations between the contributions of intermediate states can explain the different theoretical predictions. For the EFT, we also present results for two-neutrino ββ decays to the first excited 0 + state in other nuclei.

We investigate neutrinoless double-beta decay (0νββ) in the minimal extension of the standard model of particle physics, the νSM, where gauge-singlet right-handed neutrinos give rise to Dirac and Majorana neutrino mass terms. We focus on the associated sterile neutrinos and argue that the usual evaluation of their contributions to 0νββ, based on mass-dependent nuclear matrix elements, is missing important contributions from neutrinos with ultrasoft and hard momenta. We identify the hadronic and nuclear matrix elements that enter the new contributions, and calculate all relevant nuclear matrix elements for 136 Xe using the nuclear shell model. Finally, we illustrate the impact on 0νββ rates in specific neutrino mass models and show that the new contributions significantly alter the 0νββ rate in most parts of the νSM parameter space.

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