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Mineral nanoparticle suspensions with consolidating properties have been successfully applied in the restoration of weathered architectural surfaces. However, the design of these consolidants is usually stone-specific and based on trial and error, which prevents their robust operation for a wide range of highly heterogeneous monumental stone materials. In this work, we develop a facile and versatile method to systematically study the consolidating mechanisms in action using a surface forces apparatus (SFA) with real-time force sensing and an X-ray surface forces apparatus (X-SFA). We directly assess the mechanical tensile strength of nanosilica-treated single mineral contacts and show a sharp increase in their cohesion. The smallest used nanoparticles provide an order of magnitude stronger contacts. We further resolve the microstructures and forces acting during evaporation-driven, capillary-force-induced nanoparticle aggregation processes, highlighting the importance of the interactions between the nanoparticles and the confining mineral walls. Our novel SFA-based approach offers insight into nano- and microscale mechanisms of consolidating silica treatments, and it can aid the design of nanomaterials used in stone consolidation.

The presence of KIR2DS1 does not predict enhanced NK cell alloreactivity

Karin Melanie Cabanillas Stanchi,1,* Martin Ebinger,1,* Ulrike Hartmann,2 Manon Queudeville,1 Judith Feucht,1 Michael Ost,1 Marie-Sarah Koch,1 Carmen Malaval,1 Markus Mezger,1 Sarah Schober,1 Simone Weber,1 Sebastian Michaelis,1 Veit Lange,1 Peter Lang,1 Rupert Handgretinger,1 Michaela Döring1 1Department of General Pediatrics, Hematology/Oncology, University Children‘s Hospital Tübingen, Tübingen 72076, Germany; 2University Pharmacy, Eberhard-Karls-University of Tübingen, Tübingen 72076, Germany*These authors contributed equally to this workCorrespondence: Michaela DöringUniversity Hospital Tübingen - Children’s Hospital, Department I – General Pediatrics, Hematology/Oncology, Hoppe-Seyler-Str. 1, Tübingen 72076, GermanyTel +49-(0)7071-2981355Fax +49-(0)7071-295203Email michaela.doering@med.uni-tuebingen.deBackground: Chemotherapy-induced nausea and vomiting (CINV) are a major burden for patients undergoing emetogenic chemotherapy. International guidelines recommend an antiemetic prophylaxis with corticosteroids, 5-HT3R-antagonists and NK1R-antagonists. The NK1R-antagonist fosaprepitant has shown favorable results in pediatric and adult patients. There is little pediatric experience with fosaprepitant.Methods: This non-interventional observation study analyzed 303 chemotherapy courses administered to 83 pediatric patients with a median age of 9 years (2–17 years), who received antiemetic prophylaxis either with fosaprepitant and granisetron with or without dexamethasone (fosaprepitant group/FG; n=41), or granisetron with or without dexamethasone (control group/CG; n=42), during moderately (CINV risk 30–90%) or highly (CINV risk>90%) emetogenic chemotherapy. The two groups’ results were compared with respect to the safety and efficacy of the antiemetic prophylaxis during the acute (0-24hrs after chemotherapy), delayed (>24

QC 20190514

After a century of research, the potential-dependent ion distribution at electrode/electrolyte interfaces is still under debate. In particular for solvent-free electrolytes such as room-temperature ionic liquids, classical theories for the electrical double layer are not applicable. Using a combination of in situ high-energy X-ray reflectivity and impedance spectroscopy measurements, we determined this distribution with sub-molecular resolution. We find oscillatory charge density profiles consisting of alternating anion- and cation-enriched layers at both cathodic and anodic potentials. This structure is shown to arise from the same ion-ion correlations dominating the liquid bulk structure. The relaxation dynamics of the interfacial structure upon charging/discharging were studied by impedance spectroscopy and time resolved X-ray reflectivity experiments with sub-millisecond resolution. The analysis revealed three relaxation processes of vastly different characteristic time scales: a 2 ms scale interface-normal ion transport, a 100 ms scale molecular reorientation, and a minute scale lateral ordering within the first layer.

In the present contribution, we investigated catalytically active mixtures of 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and aqueous H2O2 by molecular dynamics simulations. It is clearly observable that the HFIP molecule strongly binds to the H2O2, which is necessary for the desired catalytic reaction to occur. Upon the addition of the substrate cyclooctene to the solution, this interaction is enhanced, which suggests that the catalytic activity is increased by the presence of the hydrocarbon. We could clearly observe the microheterogeneous structure of the mixture, which is the result of the separation of the hydroxyl groups, water, and H2O2 from the fluorinated alkyl moiety in the form of large domains, which span through large areas of the system. The hydrocarbon, however, does not fit into either one of these two microphases, and it forms separate aggregates in the macroscopically homogeneous liquid, creating thereby a triphilic mixture. The latter kinds of aggregates are mostly surrounded by the fluorous moieties, and therefore, the H2O2 has to move from the polar through the fluorous domain to be able to react with the cyclooctene. Accordingly, the present reaction should be described figuratively as a phase transfer or an interfacial reaction, rather than a homogeneous liquid-phase process.

On the surface of water ice, a quasi-liquid layer (QLL) has been extensively reported at temperatures below its bulk melting point at 273 K. Approaching the bulk melting temperature from below, the thickness of the QLL is known to increase. To elucidate the precise temperature variation of the QLL, and its nature, we investigate the surface melting of hexagonal ice by combining noncontact, surfacespecific vibrational sum frequency generation (SFG) spectroscopy and spectra calculated from molecular dynamics simulations. Using SFG, we probe the outermost water layers of distinct single crystalline ice faces at different temperatures. For the basal face, a stepwise, sudden weakening of the hydrogen-bonded structure of the outermost water layers occurs at 257 K. The spectral calculations from the molecular dynamics simulations reproduce the experimental findings; this allows us to interpret our experimental findings in terms of a stepwise change from one to two molten bilayers at the transition temperature.