Plasma-wall-interaction in ECRIS II

In an ECR-discharge, where the plasma is confined inside a copper-resonator by a simple magnetic mirror, it could be shown that sputtering of wall material has an important influence upon the plasma [1]. Spectroscopic measurements in ECRIS II with a copper vessel confirmed this model. Evidence for the presence of copper atoms and ions in the plasma could be found by ion extraction as well as with VUV-spectrometry. In a nitrogen discharge by adding helium as a mixing-gas we found that the extracted current of Cu-ions decreased and measured line intensities of copper emission lines dropped down. [1] D. Meyer, "Einfluss der Plasmainstabilitaet auf die Produktion hochgeladener Ionen in einer ECR-Entladung", Dissertation, Bochum, 199

Data-driven chance constrained programs over wasserstein balls

We provide an exact deterministic reformulation for data-driven, chance-constrained programs over Wasserstein balls. For individual chance constraints as well as joint chance constraints with right-hand-side uncertainty, our reformulation amounts to a mixed-integer conic program. In the special case of a Wasserstein ball with the 1-norm or the ∞-norm, the cone is the nonnegative orthant, and the chance-constrained program can be reformulated as a mixed-integer linear program. Our reformulation compares favorably to several state-of-the-art data-driven optimization schemes in our numerical experiments

"Sensory Fit Panel" – Development of a new Advertising Claim Support method to assess aesthetic diaper fit performance in an objective, reliable and reproducible way

For the product design of diapers, the fit on the baby plays a significant role. In particular, innovation in the areas of fit and freedom of movement have become increasingly important as lower order needs like leakage are sufficiently met by most products. Today’s methods to measure diaper fit focus on technical measurements (engineering and technical fit) and parents’ subjective perceptions. While these methods are useful tools for product development purposes, they are not seen as sufficient for Advertising Claim Support needs. However, when a new fit innovation should be advertised, particularly when this is done in a competitive way, a robust technical support is needed to defend this claim in case of challenges by competitors or regulatory bodies. For this purpose, methods need to be objective and technically sound in order to be acceptable to advertising regulatory bodies. Independent, objective ratings would substantiate claims on a more reliable and reproducible base. To meet this need, the diaper fit sensory panel method was developed. This test reapplies the established sensory methodology used, e.g. to assess taste or smell in food and beverages

Optimistic distributionally robust optimization for nonparametric likelihood approximation

The likelihood function is a fundamental component in Bayesian statistics. However, evaluating the likelihood of an observation is computationally intractable in many applications. In this paper, we propose a non-parametric approximation of the likelihood that identifies a probability measure which lies in the neighborhood of the nominal measure and that maximizes the probability of observing the given sample point. We show that when the neighborhood is constructed by the Kullback-Leibler divergence, by moment conditions or by the Wasserstein distance, then our optimistic likelihood can be determined through the solution of a convex optimization problem, and it admits an analytical expression in particular cases. We also show that the posterior inference problem with our optimistic likelihood approximation enjoys strong theoretical performance guarantees, and it performs competitively in a probabilistic classification task

Habitual night waking associates with dynamics of waking cortical theta power in infancy

The implications of the substantial individual differences in infant sleep for early brain development remains unclear. Here, we examined whether night sleep quality relates to daytime brain activity, operationalised through measures of EEG theta power and its dynamic modulation, which have been previously linked to later cognitive development (Braithwaite et al., 2020, Jones et al., 2020). For this longitudinal study 76 typically developing infants were studied (age: 4-14 months, 166 individual study visits) over the course of 6 months with 1, 2, 3, or 4 lab visits. Habitual sleep was measured with a 7-day sleep diary and actigraphy, and the BISQ. 20-channel EEG was recorded while infants watched multiple rounds of videos of women singing nursery rhymes; oscillatory power in the theta band was extracted. Key metrics were average theta across stimuli, and the slope of change in theta within the first novel movie. Both objective and subjective sleep assessment methods showed a relationship between more night waking, and higher overall theta power and reduced dynamic modulation of theta over the course of the novel video stimuli. These results may indicate altered learning and consolidation in infants with more disrupted night sleep, which may have implications for cognitive development

Angular Forces Around Transition Metals in Biomolecules

Quantum-mechanical analysis based on an exact sum rule is used to extract an semiclassical angle-dependent energy function for transition metal ions in biomolecules. The angular dependence is simple but different from existing classical potentials. Comparison of predicted energies with a computer-generated database shows that the semiclassical energy function is remarkably accurate, and that its angular dependence is optimal.Comment: Tex file plus 4 postscript figure

A compact laboratory transmission X-ray microscope for the water window

In the water window (2.2-4.4 nm) the attenuation of radiation in water is significantly smaller than in organic material. Therefore, intact biological specimen (e.g. cells) can be investigated in their natural environment. In order to make this technique accessible to users in a laboratory environment a Full-Field Laboratory Transmission X-ray Microscope (L-TXM) has been developed. The L-TXM is operated with a nitrogen laser plasma source employing an InnoSlab high power laser system for plasma generation. For microscopy the Ly α emission of highly ionized nitrogen at 2.48 nm is used. A laser plasma brightness of 5 × 1011 photons/(s × sr × μm2 in line at 2.48 nm) at a laser power of 70 W is demonstrated. In combination with a state-of-the-art Cr/V multilayer condenser mirror the sample is illuminated with 106 photons/(μm2 × s). Using objective zone plates 35-40 nm lines can be resolved with exposure times < 60 s. The exposure time can be further reduced to 20 s by the use of new multilayer condenser optics and operating the laser at its full power of 130 W. These exposure times enable cryo tomography in a laboratory environment

Jet-veto in bottom-quark induced Higgs production at next-to-next-to-leading order

We present results for associated Higgs+n-jet production in bottom quark annihilation, for n=0 and n>=1 at NNLO and NLO accuracy, respectively. We consider both the cases with and without b-tagging. Numerical results are presented for parameters relevant for experiments at the LHC.Comment: 27 pages, 13 figures, 8 table