Murdockmccallum6982

A series of macrocyclic molecules were self-assembled via imine condensation. In order to overcome the insolubility and lability of the amino precursors, amine deprotection and imine condensation are performed in a one-pot manner. Conformation preorganization of the precursors leads to high-yielding self-assembly of the cage products.Total synthesis of isatindigotindoline C, a 3,3'-spiropyrrolidine oxindole alkaloid, is achieved in two steps using an exo-selective decarboxylative 1,3-dipolar cycloaddition as the key step. The synthesis verifies the originally assigned relative anti-stereochemistry for the bis-oxindole core of isatindigotindoline C.We see affordability as a key challenge in making organs-on-chips accessible to a wider range of users, particularly outside the highest-resource environments. Here, we present an approach to barrier-on-a-chip fabrication based on double-sided pressure-sensitive adhesive tape and off-the-shelf polycarbonate. Besides a low materials cost, common also to PDMS or thermoplastics, it requires minimal (€100) investment in laboratory equipment, yet at the same time is suitable for upscaling to industrial roll-to-roll manufacture. We evaluate our microphysiological system with an epithelial (Caco-2/BBe1) barrier model of the small intestine, studying the biological effects of permeable support pore size, as well as stimulation with a common food compound (chili pepper-derived capsaicinoids). BIRB 796 chemical structure The cells form tight and continuous barrier layers inside our systems, with comparable permeability but superior epithelial polarization compared to Transwell culture, in line with other perfused microphysiological models. Permeable support pore size is shown to weakly impact barrier layer integrity as well as the metabolic cell profile. Capsaicinoid response proves distinct between culture systems, but we show that impacted metabolic pathways are partly conserved, and that cytoskeletal changes align with previous studies. Overall, our tape-based microphysiological system proves to be a robust and reproducible approach to studying physiological barriers, in spite of its low cost.Highly ordered superstructures of semiconductor nanocrystals contain abundant nanometer-scale pores between the crystals; however, there have been difficulties in controlling the size and orientation of these nanospaces without the use of a template or a capping reagent. This constraint has affected their development and applications in potential fields including catalysis and optoelectronics adversely. In this study, we synthesized a rod-shaped TiO2 mesocrystal (TMC) having a length of a few hundreds of micrometers and comprising regularly ordered anatase TiO2 nanocrystals that form oriented nanospaces by exposed 001 facets. Finite-difference time-domain (FDTD) calculations of electric fields and in situ fluorescence imaging with a polarization sensitive dye on a single mesocrystal were performed to reveal anisotropic adsorption and excitation of the dyes. Furthermore, the photodegradation of the dyes was found to be more facilitated in nanospaces formed by the specific facets, as compared with the dyes randomly adsorbed on the outer surfaces. Consequently, the selectivity of photocatalytic reactions based on the molecular size and redox was enhanced by introducing the concept of oriented nanospace.Direct machining and imprinting of Si are beneficial for simplifying the fabrication of microelectromechanical systems, nanoelectromechanical systems, optical devices, and fin field-effect transistors, and for reducing process costs. Electrochemical micromachining has been introduced for highly doped Si, but complex structures cannot be imprinted directly. With chemical imprinting, complex nano/micropatterns can be imprinted even on low-doped Si, but the physical contact can damage the templates. In this study, we demonstrated an electrochemical local etching (ELE) method for fabricating nano/micrometer structures on semiconductors in a noncontact manner. Polygon tips were prepared as templates on highly doped n-type Si via etching in KOH. A constant space is maintained between the template and the target Si using a gap layer to prevent damage and contamination. In the etchant vapor, the voltage bias between the template and the target Si leads to condensation of the etchant. Because the etching region is localized by the condensation of the etchant, even low-doped semiconductors can be imprinted in submicrometer patterns in a single step. When the etchant condensation is suppressed, the etching area is reduced and the resolution is increased, allowing direct imprinting of the polygonal submicrometer pattern. ELE has the potential to produce complex nano/micrometer structures in a single step without photoresists and physical contact.We report a way to make an air-gap-embedded flexible film to reduce the screen-door effect (SDE) in virtual reality (VR) displays. Oxygen plasma was treated with a polyethylene terephthalate substrate to produce wavelength-scale micropatterns. These micropatterns induce an effective haze, but it is easily destroyed by a very small external scratch. Such a problem could be solved by coating the patterns with poly(dimethylsiloxane) (PDMS). The viscosity of PDMS, controlled by the ratio of the base and curing agents, plays a key role in determining the size of air-gaps at the valleys of micropatterns. As the ratio of base agent increases to 40, the average haze abruptly increased from 0.9% to 88.6% in visible wavelengths, while the average total transmittance maintained was between 89.8 and 91.7%. The origin of air-gap-induced haze is confirmed by numerical simulations. The hazy film remarkably reduced the SDE of the VR display from 30.27% to 4.83% for red color, from 21.82% to 2.58% for green, and from 26.02% to 3.38% for blue, as the size of air-gaps increases from 0 to 406 ± 91 nm. No defects were found after 10 000 bending cycles with a bending radius of 3 mm.Phenanthroline based ligands have shown potential performance for partitioning trivalent actinides from lanthanides. In this work, we have explored four ester and amide ligands based on the phenanthroline skeleton and elucidated the separation mechanism between Am(iii) and Eu(iii) ions. The molecular geometries and extraction reactions of the metal-ligand complexes were modeled by using scalar-relativistic density functional theory. The results show that the amide based ligands have stronger coordination ability with the metal ions than the corresponding ester based ligands. According to the thermodynamic results, ligands N,N'-diethyl-N,N'-ditolyl-2,9-diamide-1,10-phenanthroline (L2) and N,N'-(1,10-phenanthroline-2,9-diyl)bis(N-ethyl-P-methyl-N-(p-tolyl)phosphinic amide) (L4) appear to have the strongest complexing ability, which is supported by the result of electrostatic potential (ESP) and the M-OL bond orders. Moreover, ligand L2 has excellent selectivity for Am(iii)/Eu(iii) among the four ligands. Additionally, the bonding properties between the metal ions and the ligands reveal that the Am(iii)/Eu(iii) selectivity stems from the Am-N bonds with more covalent character, which is supported by the analysis of the hardness of the ligands and the bond orders.