Composite Yb : YAG/Cr4+: YAG ceramics picosecond microchip lasers

Efficient laser-diode pumped picosecond self-Q-switched all-ceramic composite Yb: YAG/ Cr4+: YAG microchip lasers with 0.72 MW peak power has been developed. Lasers with nearly diffraction-limited beam quality (M-2 < 1.09), oscillate at stable single- and multi- longitudinal-modes due to the combined etalon effects in the Yb:YAG and Cr4(+:) YAG parts of its binary structure. (C) 2007 Optical Society of America

Infrared and upconversion spectroscopic studies of high Er3+content transparent YAG ceramic

In this article, we report the detailed spectroscopic studies of high Er3+content (50%) transparent YAG ceramic co-doped with nominal Cr3+ content (0.1 mol %). Various radiative and non-radiative spectroscopic properties such as radiative decay time, fluorescence branching ratio, emission/absorption cross sections, internal radiative quantum yields of the infrared and the upconverted emission bands are explored using standard experimental and theoretical methods and compared with YAG single crystal. Results show that although the non-radiative losses are high for 50% Er doped ceramic; several radiative spectral properties are almost in agreement with those for the single crystal YAG. Furthermore, because of the low dopant concentration of Cr3+, the sensitizing effect of Cr3+ was not observed. © 2011 Optical Society of America

Near-diffraction-limited passively Q-switched Yb : Y3Al5O12 ceramic lasers with peak power > 150 kW

Laser-diode pumped nearly diffraction-limited beam quality (M-2 < 1.05), high peak power, subnanosecond passively Q-switched Yb:Y3Al5O12 ceramic miniature laser with Cr4+:Y3Al5O12 ceramic as saturable absorber has been achieved. The slope efficiency is as high as 36% for 80% initial transmission of Cr4+:Y3Al5O12 ceramic. The pulse width of 335 ps and peak power of over 150 kW at repetition rate of 5 kHz were obtained. Laser oscillates at single-longitudinal-mode oscillation and wide-separated multilongitudinal-mode oscillation due to the combined etalon effect of the Cr4+:YAG thin plate and thin glass plate as output coupler. (c) 2007 American Institute of Physics

Laser-diode pumped heavy-doped Yb : YAG ceramic lasers

Laser performance of heavy-doped Yb:YAG ceramics was investigated using a two-pass pumping miniature laser configuration. Slope efficiency of 52% and optical-to-optical efficiency of 48% have been achieved for 1-mm-thick YAG ceramic doped with 20 at. % ytterbium ions. Laser spectra of Yb:YAG ceramic and single-crystal lasers were addressed under different intracavity laser intensities. Heavy-doped Yb:YAG ceramic is more suitable for a thin disk laser than a single-crystal with the same Yb3+-ion lasants. (c) 2007 Optical Society of America

Ytterbium and chromium doped composite Y3Al5O12 ceramics self-Q-switched laser

Composite Yb:Y3Al5O12/Cr:Y3Al5O12 ceramics were fabricated by using vacuum sintering technique and nanocrystalline technology. Self-Q-switched composite Yb:Y3Al5O12/Cr:Y3Al5O12 ceramic lasers with pulse energy of 125 mu J and peak power of over 105 kW at repetition rate of 3.8 kHz have been demonstrated. Nearly diffraction-limited beam quality with M-2 less than 1.35 was achieved in this composite Yb:Y3Al5O12/Cr:Y3Al5O12 ceramic self-Q-switched lasers. (C) 2007 American Institute of Physics

New nonlinear-laser effects in crystalline fine-grained ceramics based on cubic Sc2O3 and Lu2O3 oxides: second and third harmonic generation, and cascaded self-sum-frequency mixing in UV spectral region

We report on the first observation of the nonlinear cascading chi((3)) chi((3)) effects in UV spectral range and second harmonic generation stipulated by the "defect" nonlinearity under one-micron pumping in crystalline ceramics based on cubic oxides Sc2O3 and Lu2O3. Broadband their multi-wavelength Stokes and anti-Stokes combs with the extension of 10475 cm(-1) (for Sc2O3) and 8232 cm(-1) (for Lu2O3) were recorded as well

Mechanical and optical properties of Lu2O3 host-ceramics for Ln(3+) lasants

Micro-hardness and fracture toughness, as well as linear optical properties (full transmission spectrum and refractive index dispersion) of fine-grained Lu2O3 ceramics fabricated by VSN method are presented

Arabidopsis IRE1 catalyses unconventional splicing of bZIP60 mRNA to produce the active transcription factor

IRE1 plays an essential role in the endoplasmic reticulum (ER) stress response in yeast and mammals. We found that a double mutant of Arabidopsis IRE1A and IRE1B (ire1a/ire1b) is more sensitive to the ER stress inducer tunicamycin than the wild-type. Transcriptome analysis revealed that genes whose induction was reduced in ire1a/ire1b largely overlapped those in the bzip60 mutant. We observed that the active form of bZIP60 protein detected in the wild-type was missing in ire1a/ire1b. We further demonstrated that bZIP60 mRNA is spliced by ER stress, removing 23 ribonucleotides and therefore causing a frameshift that replaces the C-terminal region of bZIP60 including the transmembrane domain (TMD) with a shorter region without a TMD. This splicing was detected in ire1a and ire1b single mutants, but not in the ire1a/ire1b double mutant. We conclude that IRE1A and IRE1B catalyse unconventional splicing of bZIP60 mRNA to produce the active transcription factor

First-in-Human Phase I Study of an Oral HSP90 Inhibitor, TAS-116, in Patients with Advanced Solid Tumors.

HSP90 is involved in stability and function of cancer-related proteins. This study was conducted to define the MTD, safety, pharmacokinetics, pharmacodynamics, and preliminary antitumor efficacy of TAS-116, a novel class, orally available, highly selective inhibitor of HSP90. Patients with advanced solid tumors received TAS-116 orally once daily (QD, step 1) or every other day (QOD, step 2) in 21-day cycles. Each step comprised a dose escalation phase to determine MTD and an expansion phase at the MTD. In the dose escalation phase, an accelerated dose-titration design and a "3+3" design were used. Sixty-one patients were enrolled in Japan and the United Kingdom. MTD was determined to be 107.5 mg/m2/day for QD, and 210.7 mg/m2/day for QOD. In the expansion phase of step 1, TAS-116 was administered 5 days on/2 days off per week (QD × 5). The most common treatment-related adverse events included gastrointestinal disorders, creatinine increases, AST increases, ALT increases, and eye disorders. Eye disorders have been reported with HSP90 inhibitors; however, those observed with TAS-116 in the expansion phases were limited to grade 1. The systemic exposure of TAS-116 increased dose-proportionally with QD and QOD regimens. Two patients with non-small cell lung cancer and one patient with gastrointestinal stromal tumor (GIST) achieved a confirmed partial response. TAS-116 had an acceptable safety profile with some antitumor activity, supporting further development of this HSP90 inhibitor.This is a result from a first-in-human study, in which the HSP90 inhibitor TAS-116 demonstrated preliminary antitumor efficacy in patients with advanced solid tumors, including those with heavily pretreated GIST