The assembly of nanoparticles into polymer-like architectures is challenging and usually requires highly defined colloidal building blocks. Here, we show that the broad size-distribution of a simple dispersion of magnetic nanocolloids can be exploited to obtain various polymer-like architectures. The particles are assembled under an external magnetic field and permanently linked by thermal sintering. The remarkable variety of polymer-analogue architectures that arises from this simple process ranges from statistical and block copolymer-like sequencing to branched chains and networks. This library of architectures can be realized by controlling the sequencing of the particles and the junction points via a size-dependent self-assembly of the single building blocks.

We describe the design of the Sunrise Filter Imager (SuFI) and the Image Stabilization and Light Distribution (ISLiD) unit onboard the Sunrise balloon borne solar observatory. This contribution provides the necessary information which is relevant to understand the instruments' working principles, the relevant technical data, and the necessary information about calibration issues directly related to the science data.

The enhanced relaxation of hydrogen atoms of surrounding water from suitable contrast agent promotes magnetic resonance imaging as one of the most important medical diagnosis technique. The key challenge for the preparation of performant contrast agents for magnetic resonance imaging with high relaxivity is to ensure a high local concentration of contrast agent while allowing a contact between water and the contrast agent. Both requirements are answered by tailoring a semipermeable confinement for a gadolinium complex used as contrast agent. A locally high concentration is achieved by successfully encapsulating the complex in polymer nanocontainers that serves to protect and retain the complex inside a limited space. The access of water to the complex is achieved by carefully controlling the chemistry of the shell and the core of the nanocontainers. The confinement of the nanocontainers enables an increased relaxivity compared to an aqueous solution of the contrast agent. The nanocontainers are successfully applied in vivo to yield enhanced contrast in magnetic resonance imaging.

Abstract-Meridiani Planum is the first officially recognized meteorite find on the surface of Mars. It was discovered at and named after the landing site of the Mars Exploration Rover Opportunity. Based on its composition, it was classified as a IAB complex iron meteorite. Mo¨ssbauer spectra obtained by Opportunity are dominated by kamacite (a-Fe-Ni) and exhibit a small contribution of ferric oxide. Several small features in the spectra have been neglected to date. To shed more light on these features, five iron meteorite specimens were investigated as analogs to Meridiani Planum with a laboratory Mo¨ssbauer setup. Measurements were performed on (1) their metallic bulk, (2) troilite (FeS) inclusions, (3) cohenite ((Fe,Ni,Co) 3 C) and schreibersite ((Fe,Ni) 3 P), and (4) corroded rims. In addition to these room-temperature measurements, a specimen from the Mundrabilla IAB-ungrouped meteorite was measured at Mars-equivalent temperatures. Based on these measurements, the features in Meridiani Planum spectra can be explained with the presence of small amounts of schreibersite and ⁄ or cohenite and iron oxides. The iron oxides can be attributed to a previously reported coating on Meridiani Planum. Their presence indicates weathering through the interaction of the meteorite with small amounts of water.

Much interest has been expressed in this work on the role of water diffusivity in the release media as a new parameter for predicting drug release. NMR was used to measure water diffusivity in different media varying in their osmolality and viscosity. Water self-diffusion coefficients in sucrose, sodium chloride, and polymeric hydroxypropyl methylcellulose (HPMC) solutions were correlated with water uptake, disintegration, and drug release rates from trospium chloride immediate release tablets. The water diffusivity in sucrose solutions was significantly reduced compared to polymeric HPMC and molecular sodium chloride solutions. Water diffusivity was found to be a function of sucrose concentration in the media. Dosage form disintegration and drug release was to be affected by water diffusivity in these systems. This observation can be explained by hydrogen bonding formation between sugar molecules, an effect which was not expressed in sodium chloride solutions of equal osmolality. Water diffusivity and not media osmolality in general need to be considered to predict the effect of disintegration and dissolution media on drug release. Understanding the relevance of water diffusivity for disintegration and dissolution will lead to better parametrization of dosage form behavior in gastrointestinal (GI) aqueous and semisolid media.