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LIBS is a proven method for elemental analysis. It needs little to no sample preparation and relies solely on optical access to the sample. LIBS has therefore been handled as a promising analytical method for layered or structured samples with the potential to replace metallurgic cross-sections followed by SEM/EDX raster screenings. Due to the strong dependency of the ablation process on changing crater geometries, laser fluence, and plasma dynamics (e.g. laser absorption and scattering by the plasma, material dependent optical depth, reflecting coefficients, scattering processes, etc.), attributing an absolute depth to the number of laser pulses applied to the sample is not trivial. In this work, we show absolute depth recognition based on single-spot, non-scanning optical coherence tomography on LIBS craters produced with a standard LIBS setup. The results are verified with the use of ex-situ (electron-)microscopic techniques. Unlabelled Image • Non-scanning optical coherence tomography is able to measure ablation depth. • Within a single illumination spot several crater features can be acquired. • The unnecessity to scan the OCT-spot paves the way for fast measurements. • Using the un-ablated surface as reference enables in-situ applications. • Non-scanning OCT will allow for real calibrated in-situ depth profiling. [ABSTRACT FROM AUTHOR]

Abstract: Thyroid hormones induced rapid changes in phosphorylation in a membrane-containing lysate of synaptosomes purified from adult rat cerebral cortex. The in vitro addition of 3,5,3′-l-triiodothyronine or l-thyroxine strongly influenced incorporation of label from [γ-32P]-ATP into proteins in a cerebrocortical synaptosomal lysate. Incubation with 3,5,3′-l-triiodothyronine or l-thyroxine had strong biphasic dose-dependent effects on the phosphorylation of 38±1, 53±1, 62±1, and 113±1 kDa proteins (which we termed α, β, γ, and δ, respectively) and several others. Although we observed differing levels of phosphorylation among the four proteins, doses of 3,5,3′-l-triiodothyronine or l-thyroxine ranging from 1 to 30nM caused significant dose-dependent stimulation of the phosphorylation of all of them, an effect which occurred within three minutes. In each case, the enhancement of phosphorylation diminished with higher concentrations (100nM–1μM) of 3,5,3′-l-triiodothyronine. In contrast, incubations with similar doses of 3,3′,5′-l-triiodothyronine (reverse l-triiodothyronine) were without significant effect, indicating a specificity for 3,5,3′-l-triiodothyronine and l-thyroxine. Western blots of synaptosomal lysates incubated with 3,5,3′-l-triiodothyronine (1nM–1μM) demonstrated phosphorylation at the serine residues of a 112 kDa protein (matching δ) and phosphorylation at tyrosyl residues of a distinct 95 kDa protein. These data support the contention that thyroid hormones have a variety of rapid nongenomic pathways for regulation of protein phosphorylation in mature mammalian brain. [Copyright &y& Elsevier]