High-energy diode-pumped picosecond regenerative amplification at 999 nm in wavelength with a cryogenically cooled Yb:LuLiF(4) crystal

A diode-pumped, cryogenically cooled Yb:LuLiF(4) regenerative amplifier has been developed for the first time to our knowledge. A chirped-seed pulse was amplified and compressed in the regenerative amplifier, simultaneously, which generated approximately 6 mJ, 13 ps pulses at 999 nm in wavelength without a pulse compressor. Simultaneous lasing at 999 and 1024 nm, respectively, was demonstrated, which could be used for different frequency generation in the terahertz region.     

Shielded planar write head

Field calculation with a finite-element method was performed for optimization of the shielded planar head composed of a tapered pole in both down and cross track directions and a wrap-around shield. Especially, effect of the taper angle of the main pole and the gap length and the height of the shield on head field was investigated to obtain a strong head field with a sharp distribution. In order to explore potential of the planar head, comparison with a conventional head with a normal main pole with a short throat was made and feasibility of 1 Tbit/in² recording with patterned media was discussed in terms of magnetization reversals of aimed track and thermal stability of magnetization on adjacent tracks.     

Synthesis and Polymerization of Optically Active N‐Propargylphosphonamidates: A Novel Helical Polymer Carrying a P‐Chiral Center

Summary: A diastereomeric pair of novel N‐propargylphosphonamidates, HCCCH₂NHP(O)(CH₃)O‐L ‐menthyl was synthesized by the successive condensations of methylphosphonic dichloride with L ‐menthol and propargylamine. The (R)‐P‐isomer ( 1a ) was isolated, and the absolute configuration was determined by XRD. Polymerization of 1a , and a mixture of 1a and (S)‐P‐isomer ( 1b ) was carried out with a zwitterionic Rh complex as a catalyst. cis‐Stereoregular polymers with number‐average molecular weights of 5 600–9 800 were obtained in good yields. Poly( 1a ) and poly( 1a ₂₉‐co‐ 1b ₇₁) exhibited large specific rotations (+408 and −146°), and intense Cotton effects ([θ] = +2.25 and −0.9 × 10⁴ deg · cm² · dmol⁻¹) based on the conjugated polyacetylene backbone around 325 nm in CHCl₃, indicating that these polymers have helical structures, whose predominant helical senses are opposite.

Polymerization of N‐propargylphosphonamidate.     

Synthesis of γ-Cyclodextrin Pyrene-Labeled at the Hetero Rim and Its Use in Fluorescent Molecular Sensing

Fluorogenic active host labeled at the upper and lower rims of -cyclodextrin, namely, mono-3^A-deoxy-3^A-pyrenebutylamido-6^X-O-mono-pyrenebutylate-mono-altro--cyclodetrin (mixture -1,X = A, B, C, D, E, F, G, or H), has been synthesized in order to investigate their host-guest complexation with steroidal compoundsusing fluorescence spectra. Monomer and excimer fluorescence was observed for mixture host. Inclusion of a guest molecule in the cyclodextrin cavity resultedin increased monomer fluorescence and decreased excimer fluorescence. The extent of monomerand excimer fluorescence variations ofmixture -1 with the guestwas used as an indication for the sensing ability. The guest inducedfluorescence changes were measured for 10^-7 M solutions of mixture -1.The values I/I ⁰ , where I ⁰ and I are fluorescence intensities in the absence and presence of a guest, respectively, and I is I ⁰ - I, were then used to describe the sensing ability.     

Synthesis of a proposed isomer of F420 having α-glutamyl bonding

A proposed isomer of redox coenzyme F₄₂₀, having α? glutamyl bonding, has been synthesized from 8-benzyloxy-10-D-ribityl-5-deazaflavin and α-L-glutamyl-L-glutamic acid moiety, by the phosphite triester approach followed by deprotection procedures.     

Organometallic Compounds XIV. Formation of novel [4]ferrocenophanes by the acid-catalyzed reaction of 1,1′-bis (α-hydroxy-α-phenylethyl) ferrocene

The acid-catalyzed reaction of 1,1′-bis(α-hydroxy-α-phenylethyl)ferrocene gave several [4] ferrocenophanes including a peroxide derivative. Their structures have been confirmed by spectrometric methods and from a study of their reaction behavior.     

Free transportation cost inequalities via random matrix approximation

By means of random matrix approximation procedure, we re-prove Biane and Voiculescus free analog of Talagrands transportation cost inequality for measures on R in a more general setup. Furthermore, we prove the free transportation cost inequality for measures on T as well by extending the method to special unitary random matrices.Supported in part by Grant-in-Aid for Scientific Research (C)14540198 and by the program R&D support scheme for funding selected IT proposals of the Ministry of Public Management, Home Affairs, Posts and Telecommunications.Supported in part by MTA-JSPS project (Quantum Probability and Information Theory) and by OTKA T032662.Supported in part by Grant-in-Aid for Young Scientists (B)14740118.Mathematics Subject Classification (2000): Primary: 46L54, 46L53; Secondary: 60F10, 15A52, 94A17.     

A new lignan from Balanophora abbreviata and inhibition of lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression

Six lignans including a new lignan (1), beta-sitosterol glucopyranoside and phenylpropanoids were isolated from the whole plants of Balanophora abbreviata Bl. (Balanophoraceae). Their structures were determined by NMR, MS analysis and other spectroscopic methods. Lignans (1, 2 and 4) showed potent inhibitory activities on the lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression in RAW 264.7 cells.     

3-epicabraleahydroxylactone and other triterpenoids from camellia oil and their inhibitory effects on Epstein-Barr virus activation

The structure of a triterpenoid isolated from the nonsaponifiable lipid (NSL) of the seed oil of the camellia (Camellia japonica L.; Theaceae) was established to be (20S)-3beta-hydroxy-25,26,27-trisnordammaran-24,20-olide (1; 3-epicabraleahydroxylactone) on the basis of spectroscopic and chemical methods. Six other triterpenoids isolated from the NSL were identified as 3-epicabraleadiol (2), ocotillol II (3), ocotillol I (4), dammarenediol II (5), (20R)-taraxastane-3beta,20-diol (6), and lupane-3beta,20-diol (7). Upon evaluation of the seven triterpenoids (1-7) with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, three compounds (5-7) showed potent inhibitory effects against EBV-EA induction (IC(50) values of 277-420 mol ratio/32 pmol TPA).