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Manufactured nanomaterials (MNMs) selected from a library of over 120 different MNMs with varied compositions, sizes, and surface coatings were tested by four different laboratories for toxicity by high-throughput/-content (HT/C) techniques. The selected particles comprise 14 MNMs composed of CeO, Ag, TiO, ZnO and SiO with different coatings and surface characteristics at varying concentrations. The MNMs were tested in different mammalian cell lines at concentrations between 0.5 and 250 µg/mL to link physical-chemical properties to multiple adverse effects. The cell lines are derived from relevant organs such as liver, lung, colon and the immune system. Endpoints such as viable cell count, cell membrane permeability, apoptotic cell death, mitochondrial membrane potential, lysosomal acidification and steatosis have been studied. Soluble MNMs, Ag and ZnO, were toxic in all cell types. TiO and SiO MNMs also triggered toxicity in some, but not all, cell types and the cell type-specific effects were influenced by the specific coating and surface modification. CeO MNMs were nearly ineffective in our test systems. Differentiated liver cells appear to be most sensitive to MNMs, Whereas most of the investigated MNMs showed no acute toxicity, it became clear that some show adverse effects dependent on the assay and cell line. Hence, it is advised that future nanosafety studies utilise a multi-parametric approach such as HT/C screening to avoid missing signs of toxicity. Furthermore, some of the cell type-specific effects should be followed up in more detail and might also provide an incentive to address potential adverse effects in vivo in the relevant organ.

The 56 tonne high resolution liquid scintillation calorimeter KARMEN at the beam stop neutrino source ISIS has been used to search for neutrino oscillations in the disappearance channel νe→ νx . The νe emitted in µ + decay at rest are detected with spectroscopic quality via the exclusive charged current reaction 12 C ( νe , e − ) 12 Ng.s. almost free of background. Analysis of the spectral shape of e − from the νe-induced reaction as well as a measurement of the absolute νe flux allow to investigate oscillations of the type νe→ ντ and νe→ νµ. The flux independent ratio R CC/NC of charged current events 12 C ( νe , e − ) 12 Ng.s. to neutral current events 12 C ( ν , ν ′ ) 12 C * provides additional information in the oscillation channel νe→ νx. All three analysis methods show no evidence for oscillations. For the νe→ ντ channel 90% CL limits of sin 2 (2Θ) < 0.338 for ∆m 2 ≥ 100 eV 2 /c 4 and ∆m 2 < 0.77 eV 2 /c 4 for maximal mixing in a simple 2 flavor oscillation formalism are derived. A complete 3 flavor analysis of the experimental data from five years of measurement with respect to νe↔ ντ and νe↔ νµ mixing is presented.

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