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The thermo-responsive behavior of Poly(N-isopropylacrylamide) makes it an ideal candidate to easily embed cells and allows the polymer mixture to be injected. However, P(NiPAAm) hydrogels possess minor mechanical properties. To increase the mechanical properties, a covalent bond is introduced into the P(NIPAAm) network through a biocompatible thiol-ene click-reaction by mixing two polymer solutions. Co-polymers with variable thiol or acrylate groups to thermo-responsive co-monomer ratios, ranging from 1% to 10%, were synthesized. Precise control of the crosslink density allowed customization of the hydrogel's mechanical properties to match different tissue stiffness levels. Increasing the temperature of the hydrogel above its transition temperature of 31 °C induced the formation of additional physical interactions. These additional interactions both further increased the stiffness of the material and impacted its relaxation behavior. The developed optimized hydrogels reach stiffnesses more than ten times higher compared to the state of the art using similar polymers. Furthermore, when adding cells to the precursor polymer solutions, homogeneous thermo-responsive hydrogels with good cell viability were created upon mixing. In future work, the influence of the mechanical micro-environment on the cell's behavior can be studied in vitro in a continuous manner by changing the incubation temperature. [ABSTRACT FROM AUTHOR]

The etherification of β-citronellene with bioalcohols over zeolite beta was performed in a continuous flow liquid phase reactor. At 80 °C, the catalyst exhibits 50% β-citronellene conversion with a high selectivity for the etherification reaction. High chemoselectivity (90%) at the β-double bond of β-citronellene was observed, while β-citronellene isomers were formed as minor products. In order to rationalize the observed chemoselectivity, the relative stabilities of the protonated reaction intermediates were estimated using theoretical calculations. The zeolite beta catalyst exhibits high stability as well as low coke formation. Considering the industrial importance of terpene ethers as sophisticated solvents, fragrance or flavor additives, a novel and environmentally friendly synthesis is presented as an alternative to homogeneous catalysis using strong Brønsted or Lewis acids in solution. [ABSTRACT FROM AUTHOR]

One-dimensional supramolecular structures formed by adsorbing low coverages of 1,4-diisocyanobenzene on Au(111) at room temperature are obtained and imaged by scanning tunneling microscopy (STM) under ultrahigh vacuum (UHV) conditions. The structures originate from step edges or surface defects and arrange predominantly in a straight fashion on the substrate terraces along the 〈110〉 directions. They are proposed to consist of alternating units of 1,4-diisocyanobenzene molecules and gold atoms with a unit cell in registry with the substrate corresponding to four times the lattice interatomic distance. Their long 1-D chains and high thermal stability offer the potential to use them as conductors in nanoelectronic applications. [ABSTRACT FROM AUTHOR]

An abstract of the paper "Montecrinanes A-C: Triterpenes with an Unprecedented Rearranged Tetracyclic Skeleton from Celastrus vulcanicola. Insights into Triterpenoid Biosynthesis Based on DFT Calculations" is presented.

Title compounds are synthesized by iron(III)-catalyzed Prins cyclization of bis-homoallylic alcohols with aldehydes in the presence of trimethylsilyl chloride to avoid the formation of tetrahydrofurans. [ABSTRACT FROM AUTHOR]