Excited-state absorption and 1064-nm end-pumped laser emission of Nd:YVO4 single-crystal fiber grown by laser-heated pedestal growth

We present an investigation of the excited-state absorption and laser emission of a 1.0-at. %-Nd3+-doped YVO4 single-crystal fiber grown by the low-cost and versatile laser-heated pedestal growth technique. Efficient laser emission at 1064 nm was achieved when the fiber was pumped, in an end-pump cavity, by a Ti:sapphire laser at 808 nm. A continuous-wave threshold of 10 mW was observed with an efficiency of 42% with respect to the absorbed pump power and the maximum output power of 200 mW. These results are excellent when compared with those of a commercial bulk crystal adapted to the same cavity (48% efficiency, 250-mW maximum output power). Thus the fibers are characterized as strong candidates for the construction of compact lasers that can also be pumped by low-cost diode lasers.     

A molecular dynamics description of the conformational flexibility of the L-iduronate ring in glycosaminoglycans

For a synthetic hexasaccharide model it is shown that the conformational flexibility of the L-iduronate ring in glycosaminoglycans can be adequately described by using the PME methodology together with simulation protocols suitable for highly charged systems.     

A programmable molecular diode driven by charge-induced conformational changes

The 3-nitro-2-(3'-nitro-2'-ethynylpyridine)-5-thiopyridine molecule shows charge-induced conformational switching and a rectifying behavior with a charge-induced controllable switching. This device can be used as a memory operated with an external field interacting with one of the rings local dipole. Alternatively, the molecule can be used as a nano-actuator controlling the rotation of the ring by charging the molecule with a bias voltage.     

Synthesis of monodisperse superparamagnetic Fe/silica nanospherical composites

A new method for the synthesis of monodisperse superparamagnetic nanospherical composites with a core containing metallic alpha-Fe nanocrystals dispersed in a silica matrix, and a shell only containing silica, is reported. Essential to the formation of this microstructure is to work with lamellar-like structures in conditions close to the upper-phase boundary limit for formation of microemulsions, and to control the solubility and pH of the metallic precursors. An advantage of the method is its versatility, which allows us to change the particle size (both for the nanomagnets and for the composite) and the spatial arrangement of the nanomagnets in the matrix. Our results indicate that this material could be adequate for biotechnology applications.     

A novel sulfonamidoglycosylation of glycals

[reaction: see text] The sulfonamidoglycosylation of benzylated glycals using a catalytic amount of triphenylphosphine hydrobromide proceeded in a highly stereoselective fashion to give the beta anomers with good to high yields. This process was demonstrated with d-galactal and d-glucal. Two of the new N-2-(deoxyglycosyl)sulfonamides were tested as inhibitors of tumor cell growth in vitro and showed antiproliferative properties in the micromolar range.     

Aziridines as a protecting and directing group. Stereoselective synthesis of (+)-bromoxone

[reaction: see text] The directing ability of an aziridine group for the epoxidation of adjacent double bonds is demonstrated. The aziridine group is also used to effectively protect a double bond in a cycloenone system for a short synthesis of the title compound.     

Highly stereoselective aldol reactions of titanium enolates from lactate-derived chiral ketones

[reaction: see text] Highly stereoselective titanium-mediated aldol reactions based on lactate-derived ketones are reported. The stereochemical outcome of the process depends on the protecting group (PMB or Bn) and the Lewis acid (i-PrOTiCl(3) or TiCl(4)) used in the enolization step, the corresponding anti-syn or syn-syn aldols being prepared in high yields and with diastereomeric ratios up to 99:1.     

Anatomical location of Macrophage Migration Inhibitory Factor in urogenital tissues,peripheral ganglia and lumbosacral spinal cord of the rat

Background

Previous work suggested that macrophage migration inhibitory factor (MIF) may be involved in bladder inflammation. Therefore, the location of MIF was determined immunohistochemically in the bladder, prostate, major pelvic ganglia, sympathetic chain, the L6-S1 dorsal root ganglia (DRG) and the lumbosacral spinal cord of the rat.

Results

In the pelvic organs, MIF immunostaining was prominent in the epithelia. MIF was widely present in neurons in the MPG and the sympathetic chain. Some of those neurons also co-localized tyrosine hydroxylase (TH). In the DRGs, some of the neurons that stained for MIF also stained for Substance P. In the lumbosacral spinal cord, MIF immunostaining was observed in the white mater, the dorsal horn, the intermediolateral region and in the area around the central canal. Many cells were intensely stained for MIF and glial fibrillary acidic protein (GFAP) suggesting they were glial cells. However, some cells in the lumbosacral dorsal horn were MIF positive, GFAP negative cells suggestive of neurons.

Conclusions

Therefore, MIF, a pro-inflammatory cytokine, is localized to pelvic organs and also in neurons of the peripheral and central nervous tissues that innervate those organs. Changes in MIF's expression at the end organ and at peripheral and central nervous system sites suggest that MIF is involved in pelvic viscera inflammation and may act at several levels to promote inflammatory changes.

     

-actions whose fixed data has a section

Given a collection of real vector bundles over a closed manifold , suppose that, for some is of the form , where is the trivial one-dimensional bundle. In this paper we prove that if is the fixed data of a -action, then the same is true for the Whitney sum obtained from by replacing by . This stability property is well-known for involutions. Together with techniques previously developed, this result is used to describe, up to bordism, all possible -actions fixing the disjoint union of an even projective space and a point.