Macroporous polymer nanocomposites synthesised from high internal phase emulsion templates stabilised by reduced graphene oxide

Reduced graphene oxide (rGO) is known to be electrically conductive and adsorb at oil–water interfaces. It has also been shown to mechanically reinforce bulk materials. This work combines these favourable characteristics of two-dimensional rGO to develop 3D macroporous polymer nanocomposites via emulsion templating. rGO proved to be an efficient emulsifier as only 0.2 mg/ml (with respect to the oil phase) of rGO was required to stabilise water-in-oil high internal phase emulsions (HIPE) of up to 80 vol.% internal phase. After polymerisation of the continuous minority monomer (styrene and divinylbenzene) phase, macroporous polymer nanocomposites with tuneable microstructures were obtained. The storage modulus of rGO-poly(styrene-co-divinylbenzene) HIPEs increased by almost an order of magnitude when the rGO concentration used to stabilise the HIPE template increased from 0.4 to 5.0 mg/ml. The adsorption and organisation of rGO at the o/w interface in HIPEs prior to polymerisation and partial aggregation in the polymer cell walls after polymerisation resulted in conductive nanocomposites with a rGO content of as low as 0.006 vol.% (with respect to bulk polymer volume or 0.8 mg/ml with respect to the monomer volume used in the emulsion template) compared to 0.1 vol.% for dense nanocomposites previously reported. This provided evidence for the efficient arrangement of rGO within the macroporous polymer nanocomposite, creating an electrically conductive network.     

Polymerised high internal phase emulsion cement hybrids: Macroporous polymer scaffolds for setting cements

We polymerised the continuous styrene/divinylbenzene monomer phase of high internal phase emulsions (HIPEs) containing 70 vol.% cement slurry as internal phase to synthesise polymer cement hybrid materials. These novel cement containing poly(merised)HIPEs have an interconnected bi-phasic structure consisting of an interpenetrating network of set cement and polymer. Incorporating 14 wt.% of polymer into the cement resulted in an increased compressive strain to failure as compared to pure set cement but both elastic modulus and crush strength decreased. These novel polymer cement hybrid materials have a better chemical resistance against acetic acid then pure cement and showed also no shrinkage when exposed to xylene and dodecane.     

Tropinone-Derived Alkaloids as Potent Anticancer Agents: Synthesis,Tyrosinase Inhibition,Mechanism of Action,DFT Calculation,and Molecular Docking Studies

A new series of hybrid compounds with tropinone and thiazole rings in the structure was designed and synthesized as potential anticancer agents. They were tested against human multiple myeloma (RPMI 8226), lung carcinoma (A549), breast adenocarcinoma (MDA-MB-231), and mouse skin melanoma (B16-F10) cell lines. Toxicity was tested on human normal skin fibroblasts (HSF) and normal colon fibroblasts (CCD-18Co). The growth inhibition mechanism of the most active derivative was analyzed through investigation of its effect on the distribution of cell cycle phases and ability to induce apoptosis and necrosis in RPMI 8226 and A549 cancer cells. The tyrosinase inhibitory potential was assessed, followed by molecular docking studies. Compounds 3a–3h show high anticancer activity against MDA-MB-231 and B16-F10 cell lines with IC₅₀ values of 1.51–3.03 µM. Moreover, the cytotoxic activity of the investigated compounds against HSF and CCD-18Co cells was 8–70 times lower than against the cancer cells or no toxicity was shown in our tests, with derivative 3a being particularly successful. The mechanism of action of compound 3a in RPMI 8226 cell was shown to be through induction of cell death through apoptosis. The derivatives show ability to inhibit the tyrosinase activity with a mixed mechanism of inhibition. The final molecular docking results showed for IC₅₀ distinct correlation with experiment.     

Handling epistemic and aleatory uncertainties in probabilistic circuits

Machine Learning - When collaborating with an AI system, we need to assess when to trust its recommendations. If we mistakenly trust it in regions where it is likely to err, catastrophic failures...     

First tests of standardized biocrystallization on milk and milk products

The biocrystallization method has been standardized for plant products. The standardized biocrystallization method is tested on milk and butter samples from controlled feeding trials. When computerized image analysis is applied, samples from different origins (feeding regimes) can be distinguished significantly.     

Decreased density of amygdaloid parvalbumin-positive interneurons and behavioral changes in dystonic hamsters (Mesocricetus auratus).

The dtsz hamster represents a model of primary paroxysmal nonkinesiogenic dyskinesia in which dystonic episodes can be induced by stress and anxious stimuli. This disease is regarded as a basal ganglia disorder. In fact, a deficit of striatal interneurons could play a key role in the pathophysiology in dystonic hamsters. Because the involvement of limbic structures cannot be excluded so far, the density of parvalbumin-immunoreactive (PV+) interneurons was determined in the basolateral amygdala in the present study. Compared with nondystonic hamsters, the density of PV+ interneurons was moderately decreased in the dtsz mutant. The functional consequence of this finding was examined by behavioral analyses. Examinations in the elevated plus maze and in a modified open field failed to disclose an enhanced anxiety-related behavior in dtsz hamsters (Mesocricetus auratus). A lower acoustic startle response and a stronger habituation in mutant hamsters than in controls correlated with a decreased body weight. Interestingly, prepulse inhibition was absent in mutant hamsters. The latter finding suggests a disturbed sensorimotor gating that can be related to alterations in both the basal ganglia nuclei and in limbic structures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Kontrolle des Schengener Informationssystems

Zusammenfassung  Der Hessische Datenschutzbeauftragte ist als Vertreter der Bundesl?nder neben dem BfDI Mitglied der Gemeinsamen Kontrollinstanz für das Schengener Informationssystem. Die Autorin des folgenden Beitrags vertritt ihn in dieser Kontrollinstanz und berichtet über deren Arbeitsweise in den letzten Jahren. Angelika Schriever-Steinberg Referatsleiterin Verfassungschutz, Ausl?nderrecht, Europarecht, Schengener-Informationssystem     

Variational Bayesian functional PCA

A Bayesian approach to analyze the modes of variation in a set of curves is suggested. It is based on a generative model thus allowing for noisy and sparse observations of curves. A Demmler-Reinsch(-type) basis is used to enforce smoothness of the latent (‘eigen’)functions. Inference, including estimation, error assessment and model choice, particularly the choice of the number of eigenfunctions and their degree of smoothness, is derived from a variational approximation of the posterior distribution. The proposed analysis is illustrated with simulated and real data.