Λ and K0 production in p↑p interactions at 6 GeV/c

Results on K⁰ and Λ production in p↑p interactions at 6 GeV are presented. The data are from an exposure of the Argonne 12 ft bubble chamber to a 60% transversely polarized proton beam. Results include data on Λ and K⁰ inclusive production, and on the reactions p↑p → pΛK⁺(pΣ⁰K⁺). The beam asymmetry parameter for $\text{p}\text{↑}\text{p}\text{→}\text{K}{}^0\text{(}\text{K}{}^0\text{) +}\text{X}$ is determined to be (?0.52 ± 0.12).     

The first isolable pentacoordinate 1,2 lambda 5-azaphosphetine: synthesis,X-ray crystallographic analysis,and dynamic behaviour

Cycloaddition reaction of an iminophosphorane bearing the Martin ligand with an alkyne gave the first stable 1,2 lambda 5-azaphosphetine, whose structure was determined by X-ray crystallographic analysis, and variable temperature NMR spectroscopy revealed the existence of equilibrium with the corresponding alpha-iminoalkylidenephosphorane.     

Solid-state Er:Yb:glass laser mode-locked by using single-wall carbon nanotube thin film

We design single-wall carbon nanotube (SWNT) thin-film saturable absorbers (SAs) integrated onto semiconductor distributed Bragg reflectors for mode-locking solid-state Er:Yb:glass lasers. We characterize the low nonsaturable loss, high-damage-threshold SWNT SAs and verify their operation up to a pulse fluence of 2 mJ/cm(2). We demonstrate passive fundamental continuous-wave mode locking with and without group-delay dispersion compensation. Without compensation the laser produces chirped 1.8 ps pulses with a spectral width of 3.8 nm. With compensation, we obtain 261 fs Fourier-transform-limited pulses with a spectral width of 9.6 nm.     

Accumulation of photofrin in lesions of airway stenosis rabbit models

Airway stenosis in childhood is resistant to conventional treatments. Endoscope-assisted photodynamic therapy (PDT) is a potent candidate for the therapeutic modality owing to the easy approach to the tracheal lesion and low degree of invasiveness. The aim of the present study was to examine whether a photosensitizer preferentially accumulates in the lesion of airway stenosis in order to explore the possible applicability of PDT. The tracheal mucosa of rabbits was scraped off, and the rabbits were intravenously administered with Photofrin. The tissue concentration of Photofrin was quantitatively measured by fluorometric analysis. Granulation formation was seen in the mucosa-deprived lesion, causing airway stenosis. Photofrin concentration in the granulation tissue was four-fold higher than that in the intact trachea and 10-fold higher than that in the liver, spleen, skin and muscle. Photofrin preferentially accumulated in the lesion of airway stenosis. A preliminary experiment on PDT using transtracheal illumination showed an amelioration of airway stenosis, resulting in reduction in respiratory stridor.     

Structure of cymbidine A, a monomeric peptidoglycan-related compound with hypotensive and diuretic activities, isolated from a higher plant, Cymbidium goeringii (Orchidaceae)

The structure of a new monomeric peptidoglycan-related compound with hypotensive and diuretic activities, cymbidine A (1) isolated from the orchid Cymbidium goeringii, was elucidated mainly by spectroscopic analysis. The structure of 1 was shown to involve four amino acids (D-alanin, meso-diaminopimelic acid, D-gultamic acid, and L-valine) and two amino sugars (N-acetylglucosamine and 1,6-anhydro-N-acetylmuramic acid). The sequence of the amino acids and amino sugars was determined by the analysis of 2D NMR data. The absolute stereochemistries of the three amino acids (D-Ala, D-Glu and L-Val) were determined by the modified Marfey's method, and the (6S,10R) configurations of meso-diaminopimelic acid in 1 were indicated on the basis of the CD analysis. The absolute stereochemistry of 1,6-anhydro-N-acetylmuramic acid was also determined by CD data.     

ClickFerrophos: new chiral ferrocenyl phosphine ligands synthesized by click chemistry and the use of their metal complexes as catalysts for asymmetric hydrogenation and allylic substitution

The new ferrocenyl P,P- and P,N-ligands 5 and 6 (collectively, "ClickFerrophos") were readily prepared in four steps using Click Chemistry methodology, starting from the commercially available aminoferrocene 1. Rhodium and ruthenium complexes of ClickFerrophos 5 were effective catalysts for the hydrogenation of alkenes and ketones, respectively, producing products with up to 99.7% ee. The analogous palladium complex with 6 worked well for asymmetric allylic alkylation.     

Switching of the enzymatic activity synchronized with signal recognition by an artificial DNA receptor on a liposomal membrane

We constructed a supramolecular system on a liposomal membrane that is capable of activating an enzyme via DNA hybridization. The design of the system was inspired by natural signal transduction systems, in which enzymes amplify external signals to control signal transduction pathways. The liposomal membrane, providing a platform for the system, was prepared by the self-assembly of an oligonucleotide lipid, a phospholipid and a cationic synthetic lipid. The enzyme was immobilized on the liposomal surface through electrostatic interactions. Selective recognition of DNA signals was achieved by hybridizing the DNA signals with the oligonucleotide lipid embedded in the liposome. The hybridized DNA signal was sent to the enzyme by a copper ion acting as a mediator species. The enzyme then amplified the event by the catalytic reaction to generate the output signal. In addition, our system demonstrated potential for the discrimination of single nucleotide polymorphisms.