Radiation-Induced Grafting of Ethyl Vinyl Ether onto Polyvinyl Chloride)

The radiation-induced graft polymerization of ethyl vinyl ether (EVE) onto polyvinyl chloride) (PVC) was studied under a variety of conditions. Graft copolymer and homopoly(EVE) were formed in all cases. The presence of water reduced overall polymerization rates, percentage grafting, and homopoly(EVE) molecular weights. With “superdry” EVE, grafting reached 29% at a total dose of 6.9 Mrad. Grafting to PVC films was less efficient than grafting to PVC powder. Application of a relatively poor swelling agent for PVC resulted in an increase in the efficiency of grafting. From a comparison of studies of radiation-induced EVE homopolymerization and the present work, it was concluded that dry and superdry EVE are grafted to PVC by a cationic mechanism and wet EVE is grafted mainly by a free-radical mechanism.     

Self-cleaning perovskite type catalysts for the dry reforming of methane

Gas-to-liquid processes are generally used to convert natural gas or other gaseous hydrocarbons into liquid fuels via an intermediate syngas stream. This includes the production of liquid fuels from biomass-derived sources such as biogas. For example, the dry reforming of methane is done by reacting CH₄ and CO₂, the two main components of natural biogas, into more valuable products, i.e., CO and H₂. Nickel containing perovskite type catalysts can promote this reaction, yielding good conversions and selectivities; however, they are prone to coke laydown under certain operating conditions. We investigated the addition of high oxygen mobility dopants such as CeO₂, ZrO₂, or YSZ to reduce carbon laydown, particularly using reaction conditions that normally result in rapid coking. While doping with YSZ, YDC, GDC, and SDC did not result in any improvement, we show that a Ni perovskite catalyst (Na_0.5La_0.5Ni_0.3Al_0.7O_2.5) doped with 80.9 ZrO₂ 15.2 CeO₂ gave the lowest amount of carbon formation at 800 ℃ and activity was maintained over the operating time.     

A Series of Potent CREBBP Bromodomain Ligands Reveals an Induced‐Fit Pocket Stabilized by a Cation–π Interaction

The benzoxazinone and dihydroquinoxalinone fragments were employed as novel acetyl lysine mimics in the development of CREBBP bromodomain ligands. While the benzoxazinone series showed low affinity for the CREBBP bromodomain, expansion of the dihydroquinoxalinone series resulted in the first potent inhibitors of a bromodomain outside the BET family. Structural and computational studies reveal that an internal hydrogen bond stabilizes the protein‐bound conformation of the dihydroquinoxalinone series. The side chain of this series binds in an induced‐fit pocket forming a cation–π interaction with R1173 of CREBBP. The most potent compound inhibits binding of CREBBP to chromatin in U2OS cells.     

Spectral Asymptotics for Higher-Order Ordinary Differential Equations

This paper gives one-term componentwise asymptotics for theM and spectral matrices of a self-adjoint realisation of aneven-order ordinary differential expression. The underlyinginterval is assumed to have at least one regular endpoint, andthe boundary conditions are supposed to be separated. Furthermore,the weight function and the reciprocal of the highest-ordercoefficient are supposed to be of regular variation at the regularendpoint, in the sense of Bingham, Goldie and Teugels. 1991Mathematics Subject Classification: 34B24, 34E05.     

Calix[4]arene Schiff bases—potential ligands for fluorescent studies

A series of novel double-armed calix[4]arene derivatives incorporating imine substituents were synthesised from the Schiff-base reaction of 25,27-bis[2-[(1-formyl-2-phenyl)oxy]ethyl]-p-tert-butylcalix[4]arene (1) with the appropriate amine or hydrazone. All compounds were characterised by various spectroscopic and analytical techniques, and in three cases, by X-ray crystallographic studies. In the case of compound 2, inclusion compounds were synthesised with both m-xylene and dimethylformamide and their X-ray structures revealed these inclusion sites—between the pendant arms and in the upper cavity, respectively. In all cases, the pendant arms are bent away from each rather than adopting a face-to-face conformation.     

Isoxazole‐Derived Amino Acids are Bromodomain‐Binding Acetyl‐Lysine Mimics: Incorporation into Histone H4 Peptides and Histone H3

A range of isoxazole‐containing amino acids was synthesized that displaced acetyl‐lysine‐containing peptides from the BAZ2A, BRD4(1), and BRD9 bromodomains. Three of these amino acids were incorporated into a histone H4‐mimicking peptide and their affinity for BRD4(1) was assessed. Affinities of the isoxazole‐containing peptides are comparable to those of a hyperacetylated histone H4‐mimicking cognate peptide, and demonstrated a dependence on the position at which the unnatural residue was incorporated. An isoxazole‐based alkylating agent was developed to selectively alkylate cysteine residues in situ. Selective monoalkylation of a histone H4‐mimicking peptide, containing a lysine to cysteine residue substitution (K12C), resulted in acetyl‐lysine mimic incorporation, with high affinity for the BRD4 bromodomain. The same technology was used to alkylate a K18C mutant of histone H3.     

Biomimetic total synthesis of cruentaren A via aromatization of diketodioxinones

The total synthesis of cruentaren A, a biologically active resorcylate natural product, is reported. The aromatic unit was constructed via late-stage cyclization and aromatization from a diketodioxinone intermediate and macrocyclization using Fürstner ring-closing alkyne metathesis.     

TRPM5-expressing microvillous cells in the main olfactory epithelium

Background  

The main olfactory epithelium (MOE) in the nasal cavity detects a variety of air borne molecules that provide information regarding the presence of food, predators and other relevant social and environmental factors. Within the epithelium are ciliated sensory neurons, supporting cells, basal cells and microvillous cells, each of which is distinct in morphology and function. Arguably, the least understood, are the microvillous cells, a population of cells that are small in number and whose function is not known. We previously found that in a mouse strain in which the TRPM5 promoter drives expression of the green fluorescent protein (GFP), a population of ciliated olfactory sensory neurons (OSNs), as well as a population of cells displaying microvilli-like structures is labeled. Here we examined the morphology and immunocytochemical properties of these microvillous-like cells using immunocytochemical methods.     

A robust interface enabled by electrospun membrane with optimal resistance in lithium metal batteries

A uniform diffusion layer is essential for non-dendritic deposition of lithium in high-density lithium batteries.However,natural pristine solid electrolyte interface(SEI)is always porous and inhomogeneous because of repeated breakdown and repair cycles,whereas ideal materials with excellent mechanical property for artificial SEIs remain a challenge.Herein,a robust and stable interface is achieved by spinning soft polymer associated with few MoO₃ into fibers,and thus mechanical property of fibers other than materials determines mechanical performance of the interface which can be optimized by adjusting parameters.Furthermore,lithium deposited underneath the layer is enabled by constructing an optimal resistance to make the membrane serve as an artificial SEI rather than lithium host.As a result,dendritefree lithium was observed underneath the membrane,and stable interface for long-term cycling was also indicated by EIS measurements.The lithium iron phosphate(LiFePO₄)full-cell with coated electrode demonstrated an initial capacity of 155.2 m Ah g^-1,and 80%of its original capacity was retained after 500 cycles at 2.0℃ without any additive in carbonate-based electrolyte.