Bioactive phenolic constituents from the seeds of Pharbitis nil

Two new lignans, termed pharsyringaresinol (1) and pharbilignoside (2), a new phenylethanoid glycoside, termed pharbiniloside (3), and 22 known compounds, were isolated from the ethanol extract of the seeds of Pharbitis nil. The structures of the new compounds (1-3) were determined on the basis of spectroscopic analyses, including 2D-NMR and circular dichroism (CD) spectroscopy studies. Among the isolates, compounds 2, 11, 12, and 24 exhibited significant cytotoxicity against human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT-15) with IC(50) values ranging from 8.07 to 28.30 μM. In addition, compounds 11, 12 and 24 potently inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-activated BV-2 cells, a microglia cells with IC(50) values ranging from 14.7 to 19.9 μM.     

On formulas for the velocity of Stoneley waves propagating along the loosely bonded interface of two elastic half-spaces

Formulas for the velocity of Stoneley waves propagating along the loosely bonded interface of two isotropic elastic half-spaces are derived using the complex function method. The derivation also shows that if a Stoneley wave exists, then it is unique. By using the obtained formulas, we can easily reproduce the numerical results previously obtained by Murty [G. S. Murty, Phys. Earth Planet. Interiors 11 (1975), 65–79.] by directly solving the secular equation.     

N-Methylative aziridine ring opening and asymmetric synthesis of MeBmt

Asymmetric synthesis of MeBmt, an unusual amino acid constituent of cyclosporine A, was achieved from aziridine-(2R)-carboxaldehyde through the highly stereoselective addition of (E)-crotylboronate and the subsequent N-methylative aziridine ring opening as key steps.     

Crystal Structure and Spectroscopic Properties of cis‐β‐Diazido(1,4,7,11‐tetraazaundecane)chromium(III) Bromide

The new complex, cis‐β‐[Cr(2,2,3‐tet)(N₃)₂]Br (2,2,3‐tet = 1,4,7,11‐tetraazaundecane), was prepared and its structure was determined by single‐crystal X‐ray diffraction. The chromium(III) atom is in a distorted octahedral environment coordinated by four nitrogen atoms of 2,2,3‐tet and two azido ligands in a cis‐β arrangement, with bent Cr–N₃ linkages at the coordinating azide nitrogen atoms. The mean Cr–N(2,2,3‐tet) and Cr–N(azide) bond lengths are 2.084(5) and 2.021(5) Å, respectively. The crystal structure is stabilized by ionic interactions, supported by N–H ··· N(azide) and N–H ··· Br hydrogen bonds. The IR and electronic spectroscopic properties are also discussed.     

Responsive polymer/gold nanoparticle composite thin films fabricated by solvent-induced self-assembly and spin-coating

Self-assembled poly(4-vinylpyridine)-grafted gold (Au) nanoparticles (NPs) and polystyrene-b-poly(4-vinylpyridine) block copolymers were fabricated by the introduction of a selective solvent to a common solution. The assembled mixtures were spin-coated onto solid substrates to fabricate composite gold/polymer thin films composed of copolymer-hybridized Au NPs and independent copolymer micelles. The obtained composite Au thin films had variable localized surface plasmon resonance (LSPR) bands and microscopic morphologies upon vapor annealing with selective solvents because the adsorption and dissolving of solvent molecules into the films could rearrange the copolymer block. The hybrid nanostructured Au thin films may have potential in vapor sensing and organic assays.     

A tutorial and mini-review of the ICP-MS technique for determinations of transition metal ion and main group element concentration in the neurodegenerative and brain sciences

Abstract  

New techniques in the biosciences are always welcomed and important. Reviews help in updating and disseminating information in scientific fields, especially when there are many advances such as in the vital area in neuroscience. Herein is a recent review of inductively coupled plasma mass spectrometry (ICP-MS) in the context of trace elements, relating to neurodegenerative diseases. The accurate determination of such elemental distributions in Alzheimer’s disease, Parkinson’s disease, etc. allows for a better understanding of such diseases and relates to the sensitivity and scope of the ICP-MS technique. The elements detected are often “trace” and can be analyzed for both body tissues and fluids. We discuss the practical use of ICP-MS. This includes the explanations of the instrumental setup, elements and their detection limits, a brief comparison of ICP-MS with other inorganic analysis instruments, sample preparation, and the analysis method. Next, we discuss neurodegenerative disease and metal ion analysis with ICP-MS. This includes introductions to neurodegenerative diseases, tissue analysis, fluid analysis, and bioimaging of metals in brain tissue samples, and protein analysis application with metals and ICP-MS, broken down into the subtopics of (1) isotope dilution analysis, (2) related immunoassay techniques, and (3) hyphenated instrumental applications. This article is meant to be a primer for a synthetic chemist interested in utilizing this technique and is current through the middle of 2010.     

Two-dimensional virtual array for ultrasonic nondestructive evaluation using a time-reversal chaotic cavity

Despite its introduction more than a decade ago, a two-dimensional ultrasonic array remains a luxury in nondestructive evaluation because of the complexity and cost associated with its fabrication and operation. This paper describes the construction and performance of a two-dimensional virtual array that solves these problems. The virtual array consists of only two transducers (one each for transmit and receive) and an aluminum chaotic cavity, augmented by a 10 × 10 matrix array of rectangular rods. Each rod, serving as an elastic waveguide, is calibrated to emit a collimated pulsed sound beam centered at 2.5 MHz using the reciprocal time reversal. The resulting virtual array is capable of pulse-echo interrogation of a solid sample in direct contact along 10 × 10 scan lines. Three-dimensional imaging of an aluminum test piece, the nominal thickness of which is in the order of 1 cm, is successfully carried out using the virtual array.     

Global existence and uniform decay of a damped Klein-Gordon equation in a noncylindrical domain

In this paper, we consider a damped Klein-Gordon equation in a noncylindrical domain. This work is devoted to proving the existence of global solutions and decay for the energy of solutions for a damped Klein-Gordon equation in a noncylindrical domain.     

Observation of B(s)⁰→J/ψf₀(980) and evidence for B(s)⁰→J/ψf₀(1370)

We report the observation of B(s)?→J/ψf?(980) and evidence for B(s)?→J/ψf?(1370), which are CP eigenstate decay modes. These results are obtained from 121.4 fb?1 of data collected at the Υ(5S) resonance with the Belle detector at the KEKB e(+)e? collider. We measure the branching fractions B(B(s)?→J/ψf?(980); f?(980)→π(+)π?)=(1.16(-0.19)(+0.31)(stat)(-0.17)(+0.15)(syst)(-0.18)(+0.26)(N(B(s)((*))B(s)((*)))))×10?? with a significance of 8.4σ, and B(B(s)?→J/ψf?(1370); f?(1370)→π(+)π?)=(0.34(-0.14)(+0.11)(stat)(-0.02)(+0.03)(syst)(-0.05)(+0.08)(N(B(s)((*))B(s)((*)))))×10?? with a significance of 4.2σ. The last error listed is due to uncertainty in the number of produced B(s)((*))B(s)((*)) pairs.