Complexes between the anionic polyelectrolyte sodium polyacrylate (PA) and an oppositely charged divalent azobenzene dye are prepared in aqueous solution. Depending on the ratio between dye and polyelectrolyte stable aggregates with a well-defined spherical shape are observed. Upon exposure of these complexes to UV light, the trans → cis transition of the azobenzene is excited resulting in a better solubility of the dye and a dissolution of the complexes. The PA chains reassemble into well-defined aggregates when the dye is allowed to relax back into the trans isomer. Varying the temperature during this reformation step has a direct influence on the final size of the aggregates rendering temperature in an efficient way to easily change the size of the self-assemblies. Application of time-resolved small-angle neutron scattering (SANS) to study the structure formation reveals that the cis → trans isomerization is the rate-limiting step followed by a nucleation and growth process.

Stable, creaming-free oil in water emulsions with high volume fractions of oil (ϕ = 0.05−0.40, density matched to water) and polysorbate 80 as an emulsifier were characterized without dilution by Photon Density Wave spectroscopy measuring light absorption and scattering behavior, the latter serving as the basis for droplet size distribution analysis. The emulsion with ϕ = 0.10 was used to investigate flocculation processes induced by xanthan as a semi-flexible linear nonabsorbing polymer. Different time regimes in the development of the reduced scattering coefficient μ s ′ could be identified. First, a rapid, temperature-dependent change in μ s ′ during the depletion process was observed. Second, the further decrease of μ s ′ follows a power law in analogy to a spinodal demixing behavior, as described by the Cahn− Hilliard theory.

Is presenting patients with moral reminders prior to psychological testing a fruitful deterrence strategy for symptom over-reporting? We addressed this question in three ways. In study 1, we presented individuals seeking treatment for ADHD complaints (n = 24) with moral primes using the Mother Teresa Questionnaire and compared their scores on an index of symptom over-reporting (i.e., the Structured Inventory of Malingered Symptomatology, SIMS) with those of unprimed patient controls (n = 27). Moral primes slightly decreased SIMS scores, but the effect was not significant. In study 2, we took a different approach to activate moral categories: we recruited individuals seeking treatment for ADHD complaints and asked some of them to sign a moral contract (i.e., prime; n = 19) declaring that they would complete the tests in an honest way and compared their scores on the SIMS and standard clinical scales measuring self-reported psychopathology with those of unprimed patient controls (n = 17). Again, we found no convincing evidence that moral cues suppress symptom over-reporting. In study 3, we gave individuals from the general population (N = 132) positive, negative, or neutral moral primes and implicitly induced them to feign symptoms, after which they completed a brief validated version of the SIMS and an adapted version of the b Test (i.e., an underperformance measure). Again, primes did not affect over-reporting tendencies. Taken together, our findings illustrate that moral reminders are not going to be useful in clinical practice. Rather, they point towards the importance of studying contextual and individual difference factors that guide moral decision-making in patients and may be modified to discourage symptom over-reporting.