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We describe an experimental investigation of the nonlinear optical properties of nanocomposites incorporating organic (hyperbranched polymer)-metallic (Au or Pt) nanoparticle complex embedded in polymer films. Zscan techniques are employed to measure the effective third-order nonlinear optical susceptibilities χ(3) eff of the composites with 35 ps pulses at 532 nm. The relative sign of the real and imaginary parts of χ(3) eff could be explained qualitatively by the Kramers-Kronig relation. The third-order nonlinear optical susceptibilities of Au and Pt nanoparticles from the measured values for χ(3) eff were also determined to be (-5.48 + 4.76i)×10-8 and (4.43 - 0.65i)×10-6 esu, respectively, at 532 nm.

A 74-year old man was admitted to our hospital with right diffuse pleural thickening and effusion and with subcarinal lymph node swelling. The effusion obtained by thoracentesis showed no malignant cells, although positron emission tomography showed abnormal uptake in the right pleural thickening and subcarinal lymph node. Histopathological examination of the lymph node specimens obtained by endobronchial ultrasound-guided transbronchial needle aspiration showed a sheet of epithelioid-like large atypical cells. The tumor cells were immunohistochemically positive for calretinin and cytokeratin 5/6, and negative for CEA and TTF-1. Therefore, malignant pleural mesothelioma of epithelioid type was diagnosed.

A differential optical switch based on parallel-connected AlGaAs-GaAs pnpn structures is presented. Continuous input light makes it possible to discriminate between two optical inputs with a power difference of as low as 0.1 nW. The minimum operating energy with pulse inputs was 400 fJ. With the introduction of a storage operation of pnpn structures, the optical S-R flip-flop operation is also demonstrated with a 7.2-pJ optical input energy. The expansibility of the 2-D array is attractive in optical parallel processing systems, especially in optical neural networks. >

Galectin-9 (Gal-9) plays pivotal roles in the modulation of innate and adaptive immunity to suppress T-cell-mediated autoimmune models. However, it remains unclear if Gal-9 plays a suppressive role for T-cell function in non-autoimmune disease models. We assessed the effects of Gal-9 on experimental hypersensitivity pneumonitis induced by Trichosporon asahii. When Gal-9 was given subcutaneously to C57BL/6 mice at the time of challenge with T. asahii, it significantly suppressed T. asahii-induced lung inflammation, as the levels of IL-1, IL-6, IFN-gamma, and IL-17 were significantly reduced in the BALF of Gal-9-treated mice. Moreover, co-culture of anti-CD3-stimulated CD4 T cells with BALF cells harvested from Gal-9-treated mice on day 1 resulted in diminished CD4 T-cell proliferation and decreased levels of IFN-gamma and IL-17. CD11b(+)Ly-6C(high)F4/80(+) BALF Mphi expanded by Gal-9 were responsible for the suppression. We further found in vitro that Gal-9, only in the presence of T. asahii, expands CD11b(+)Ly-6C(high)F4/80(+) cells from BM cells, and the cells suppress T-cell proliferation and IFN-gamma and IL-17 production. The present results indicate that Gal-9 expands immunosuppressive CD11b(+)Ly-6C(high) Mphi to ameliorate Th1/Th17 cell-mediated hypersensitivity pneumonitis.

We report on a GaAs/AlGaAs optical neurochip based on a three-layered feed-forward model. The optical neurochip consists of a light-emitting diode array with 66 elements, a fixed interconnection matrix, and a photodiode array with 110 elements. The interconnection matrix is determined by the backpropagation learning rule with three quantized levels. There are 35, 29, and 26 neurons, respectively, in the input, hidden, and output layers. The excitatory and inhibitory synapses are integrated on one chip. By using the chip and external electronics, we have succeeded in the recognition of 10 characters with 5 x 7 bits.

An optical flip-flop using parallel-connected pnpn (thyristor) structures is demonstrated for the first time to our knowledge. We utilize the differential optical switching technique for inverting the state of the flip-flop and the slow dissipation of carriers stored in the gate layers of pnpn structures for retaining the state. The flip-flop operation with 7.2 pJ of optical input energy was attained by using an AlGaAs/GaAs device. The expansibility to monolithic two-dimensional arrays, the high on–off contrast, and the high optical gain of the flip-flop are useful in the design and fabrication of optical parallel processing systems.

Organic nonlinear optical (NLO) materials have attracted much interest for their potential applications over the past two decades mainly because of their faster electronic response and larger optical nonlinearities than the conventional inorganic materials. Especially, electro-optic (EO) polymers have been promising candidates for fast and broadband EO modulators as a result of the development of the 2nd-order NLO chromophore. In this manuscript, we report fabrication and design of one dimensional (1D) polymeric photonic crystals (PCs) to additionally enhance the optical nonlinearities of the organic NLO materials. We fabricated polymeric high-reflection mirrors for 1D PCs by a simple alternatively spin-coating two polymers under control of their optical thickness, in which a novel polymer was applied to the higher refractive index layer. We also designed defect-mode 1D polymeric PC for effective light-localization in the defect layer and discussed their effect for enhancement of the 2nd-order optical nonlinearities.

Parallel-connected pn-pn optical switches can be used to realize pattern edge extraction. The authors describe a method of enhancing the on-edge/off-edge contrast ratio using voltage-controlled negative load resistors. Negative resistance can suppress the currents injected into the off-edge elements. In an experiment with the negative resistors based on serial-connected thyristors, a contrast ratio as high as 16:1 was obtained. >

Three new prenyl-benzoylfuranone type sesquiterpenoid derivatives, 3S*-(2, 4-dihydroxybenzoyl)-4R*, 5R*-dimethyl-5-(4, 8-dimethyl-3(E), 7(E)-nonadien-1-yl)tetrahydro-2-furanone, 3S*-(2, 4-dihydroxybenzoyl)-4R*, 5R*-dimethyl-5-[4-methyl-5-(4-methyl-2-furyl)-3(E)-penten-1-yl]tetrahydro-2-furanone and 3S*-(2, 4-dihydroxybenzoyl)-4R*, 5R*-dimethyl-5-[4-methyl-5-(4-methyl-2-furyl)-3(E)-penten-1-yl]tetrahydro-2-furanone were isolated from the roots of Ferula ferulioides. The structures were established by comprehensive spectral analysis. The biosynthetic pathway leading to their prenyl-benzoylfuranone type sesquiterpenoids is proposed based on their structures.

Several species of the general Tinospora (Menispermaceae) are widely distributed over Asia and Africa and are well-known for their medicinal properties. From the stems of Tinospora hainanensis, a new N-methyltetrahydroprotoberberine alkaloid, N-methyltetrahydrocolumbamine, was isolated and characterized on the basis of NMR, MS and X-ray.

The mutual injection-locking properties of a coupled pair of multiple-quantum-well distributed-feedback lasers with grating output couplers were investigated experimentally and theoretically. When the mutual injection locking occurred, the output of one laser decreased while that of the other increased. The locking curve was asymmetric, and a stable and an unstable locking region existed. From the theoretical analysis, it was found that the phase delay with which the electric field emitted from each laser to the other laser significantly influences the locking characteristics. The increase and decrease of the locked output power are caused by the phase delay. It is also shown that the laser which receives the larger optical injection behaves like a slave laser and the laser which has less optical injection behaves like a master laser, and the shape of the locking curve is determined by the balance between the alpha parameter and the thermal resistance. >

In order to consider the total atmospheric loadings of the PAHs (polycyclic aromatic hydrocarbons) from traffic activities, the emission factors of PAHs were estimated and from the obtained emission factors and vehicle transportation statistics, total atmospheric loadings were integrated and the loadings into the water body were estimated on a regional scale. The atmospheric concentration of PAHs was measured at the roadside of a road with heavy traffic in the Hiroshima area in Japan. The samplings were conducted in summer and winter. Atmospheric particulate matters (fine particle, 0.6–7 μm; coarse particle, over 7 μm) and their PAH concentration were measured. Also, four major emission sources (gasoline and diesel vehicle emissions, tire and asphalt debris) were assumed for vehicle transportation activities, the chemical mass balance method was applied and the source partitioning at the roadside was estimated. Furthermore, the dispersion of atmospheric particles from the vehicles was modelled and the emission factors of the sources were determined by the comparison to the chemical mass balance results. Based on emission factors derived from the modelling, an atmospheric dispersion model of nationwide scale (National Institute of Advanced Industrial Science and Technology - Atmospheric Dispersion Model for Exposure and Risk assessment) was applied, and the atmospheric concentration and loading to the ground were calculated for the Hiroshima Bay watershed area.

Simplified differential display of mRNA was applied to isolate and identify genes transcriptionally regulated in mouse liver by sho-saiko-to administration. A cDNA fragment up-regulated by sho-saiko-to was isolated and characterized. cDNA sequencing and subsequent database analysis revealed that the fragment showed significant sequence similarity with mouse testosterone 16-alpha-hydroxylase (cytochrome P-450[16alpha]) cDNA. The increased level of mRNA expression of cytochrome P-450(16alpha) in association with sho-saiko-to administration suggests the molecular mechanism of the chemopreventive effect of sho-saiko-to. This result indicates the usefulness of the mRNA differential display technique to investigate the molecular mechanism of Kampo medicine.

Five new tetranortriterpenoids, methyl 3β-tigloyloxy-2, 6-dihydroxy-1-oxo-meliac-8(30)-enate, methyl 3β-tigloyloxy-2-hydroxy-1-oxo-meliac-8(30)-enate, methyl 3β-tigloyloxy-2-hydroxy-8α, 30α-epoxy-1-oxo-meliacate, methyl 3β-acetoxy-2, 6-dihydroxy-8α, 30α-epoxy-1-oxo-meliacate and methyl 3β-isobutyryloxy-2, 6-dihydroxy-8α, 30α-epoxy-1-oxo-meliacate, were isolated from the seeds of Swietenia macrophylla. The structure of these five tetranortriterpenoids was established by comprehensive spectral analysis.

Ni(acac)2 catalyzes the five-component connection reaction of Me2Zn, alkynes, diene (of 1,3-dien-8-ynes and 1,3-dien-9-ynes), aldehydes and anisidine to furnish cyclic dienyl amines anti-2 with high remote 1,5-diastereoselectivity.

A nickel(0) species catalyzes the five-component connection reaction of dimethylzinc, alkynes, 1,3-butadiene, aldehydes, and amines, furnishing either 1 or 2 selectively in good yields depending on the kinds of amines, aromatic or aliphatic amines, respectively.

Under nickel catalysis, 1,3,8-nonatrienes and 1,3,9-decatrienes 3 react at room temperature with dimethylzinc and acetone at the alkene and diene termini, respectively, providing 1,2-disubstituted cycloalkanes 4 in good yield. The stereoselectivities of 4 provide useful information about the mechanistic frameworks for the present reaction and related cyclization reaction of ω-dienynes 1.

Under the nickel catalysis, in one pot, diethylzinc serves as a reducing agent to connect the three components of 1,3-dienes, alkyl or aryl aldehydes, and anilines to furnish 3-substituted 3,5-syn-5-(arylamino)pent-1-enes 1, the homoallylation products of aldimines with dienes, in excellent yields and with high regio- and stereoselectivity.

We have fabricated SSC-DFB laser transmitter modules, which give enough output power, and can tolerate strong reflection. They satisfy the SDH/SONET requirements for transmission up to 15 km at 2.5 Gbit/s. Because of the expected low packaging cost, the transmitter modules are expected to play a big role in the metro/access market.

We report a study of the effects of external optical feedback on the threshold and spectral characteristics of VCSELs with feedback levels in the range from /spl minus/25 dB to 0 dB. A large threshold current reduction and multi-extended-cavity-mode operation have been observed. The experimental results are in good agreement with the theoretical calculations based on a compound cavity laser model. >

The investigation of the importance of optical feedback on the optical properties of vertical-cavity surface emitting lasers (VCSELs) is important because of their potential applications in optical signal processing and light-wave communications. We report on the study of strong feedback effects on the threshold and spectral characteristics of a GaAs-AlGaAs VCSEL. Such studies have not yet been reported for VCSELs. >

Vertical cavity zone lasers (Z-lasers) operating at 980 nm and 850 nm have been fabricated. This new class of high power (>100 mW) high efficiency (/spl eta//spl ap/ 36%) large area (70 /spl mu/m diameter) vertical cavity laser has an output that is automatically focused to a spot at a particular distance away from the laser. This is in contrast to the conventional surface or edge emitting array devices that usually have multiple far-field lobes and need external optical components for focusing purposes. Among other applications, the unique properties of 980 nm Z-lasers makes them attractive as a pump laser for fiber amplifier systems.

We report on 160 Gbit/s single channel unrepeatered transmission over the record length of 200 km non-zero dispersion shifted fiber using an electro-absorption modulator for simultaneous demultiplexing and clock recovery, and distributed Raman amplification.

Polarization self‐modulation at frequencies up to 6 GHz is observed in a vertical‐cavity surface‐emitting laser. This self‐oscillation is observed when a portion of the laser output power is injected back into the laser after having rotated its polarization by 90° with respect to the initial laser polarization state. Our experiment demonstrates a simple technique for generating an ultrahigh frequency optical clock. New applications in optical storage are also envisioned.

We report over 130 °C continuous wave operation of unbonded vertical cavity top‐surface emitting lasers emitting more than 1.0 mW at 110 °C. Furthermore, we control threshold currents to within only ±1.35 mA (±12%) over a 150 °C temperature range. We are also able to control the threshold current to within a factor of 2 over a 50 nm wavelength range using the same epidesign.

We report the observation of bistable polarization switching in a vertical‐cavity surface‐emitting laser under optical injection. The wavelength dependence of the switching is measured. It is found that this polarization switching is achieved through injection locking where both the wavelength and the polarization of the vertical‐cavity laser are locked to the injected optical signal.

A micro-contact printing (µCP) method has been applied to the fabrication of microstructures and electronics. We have successfully fabricated a copper wiring structure on flexible substrates using a combination of µCP, electroless plating, and electroplating. A nucleating agent ink pattern was printed by µCP onto polyethylene terephthalate, and polyethylene naphthalate. Nickel and copper thin films were electrolessly plated onto the pattern, and used as a conductive layer for subsequent copper electroplating. Copper wiring structures with a half-pitch of a 100 µm and a 250 µm line-and-space pattern, were successfully produced on flexible films at temperatures below 100 °C.

In this paper, we examine the performance of several modulation formats in more than four dimensions for coherent optical communications systems. We compare two high-dimensional modulation design methodologies based on spherical cutting of lattices and block coding of a 'base constellation' of binary phase shift keying (BPSK) on each dimension. The performances of modulation formats generated with these methodologies is analyzed in the asymptotic signal-to-noise ratio regime and for an additive white Gaussian noise (AWGN) channel. We then study the application of both types of high-dimensional modulation formats to standard single-mode fiber (SSMF) transmission systems. For modulation with spectral efficiencies comparable to dual-polarization (DP-) BPSK, polarization-switched quaternary phase shift keying (PS-QPSK) and DP-QPSK, we demonstrate SNR gains of up to 3 dB, 0.9 dB and 1 dB respectively, at a BER of 10(-3).

Five alkaloids were isolated from the epigeal part of Oxytropis myriophylla. Three alkaloids were identified as N-benzoyl-β-phenylethylamine, N-trans-cinnamoyl-β-phenylethylamine, N-cis-cinnamoyl-β-phenylethylamine and the structures of two new alkaloids were elucidated to be N-benzoyl-β-hydroxyphenylethylarnine(2), N-trans-cinnamoyl-β-hydroxy-phenylethylamine(5). The absolu.te structures were established by modified Mosher method.

We demonstrate record high pulsed output power exceeding 530 mW from an electrically pumped phase‐coupled 8×8 vertical cavity surface emitting laser array (SELA) at room temperature. Three array types are compared: an 8×8 pixellated SELA(PSELA), an 8×8 grid contact SELA(CSELA), and a 78 μm×78 μm single broad area SEL(BSEL) emitter. The CSELA operating in a phase‐coupled supermode exhibits the lowest threshold current (100 mA) and voltage (1.6 V), highest damage threshold and a smooth L‐I characteristic with differential quantum efficiency ηd≳27%, the BSEL has the largest output power≳580 mW and a large ηd≳48%, the PSELA exhibited a large voltage with the largest ηd≳80%.

Nephritogenoside has been prepared by coupling of the acylazide derivative of N-triglycosyl dipeptide with nonadecapeptide, followed by deprotection of a desirable protected nephritogenoside

Isomers of O-alpha-D-glucopyranosyl-(1----6)-O-beta-D-glucopyranosyl- (1----6)-N-[L-aspart-1-oyl-(L-proline)-4-oyl]-alpha-D-glucopyranos ylamine have been prepared, as models for a derivative possibly present in the glomerular basement membrane of rats, by condensation of the corresponding dipeptide derivative (5) with triglycosylamine (4) in the presence of O,O-diethylcyanophosphonate, followed by deprotection of the trisaccharide-dipeptide derivative. During the deprotection process, cis- and trans-isomers containing proline were separated by silica gel column chromatography and also reversed-phase high performance liquid chromatography.

Edge extraction from optical input patterns using parallel-connected AlGaAs-GaAs pn-pn optical switches is discussed. For a binary optical input pattern, an optical output pattern with emphasis on edge elements is obtained. The contrast ratio of the output between the edge and intermediate elements is 1.3:1. Thresholding characteristics of laser diodes are effective in enhancing the contrast ratio up to 5.2:1. >

Differential optical switching operation with an optical input of as low as 400 fJ (0.07 fJ/μm2) was realized by using parallel‐connected AlGaAs/GaAs pnpn optical switches. An improvement in the sensitivity of more than two orders of magnitude has been attained by introduction of a new operating concept. The electrical transient time was 10 ns, almost independent of optical input levels.

Single quantum wells were grown on GaAs triangular gratings by molecular beam epitaxy. Cross‐sectional transmission electron microscopy revealed that the quantum wells had a triangular shape above the ridge of the grating. The photoluminescence spectra at 77 K showed strong anisotropy, indicating that the electrons are confined two dimensionally. The calculation confirmed that the electrons tend to be localized at the corner of the bent quantum well wires, and the effective width of the quantum well wire was estimated to be 30 nm.

We studied the effect of karasurin-A, a type-I ribosome-inactivating protein (RIP) isolated from fresh root tubers of Trichosanches kirilowii MAX. var. japonica KITAMURA, on the mitogenic response of murine splenocytes and nitric oxide (NO) production by murine peritoneal macrophages in vitro. Karasurin-A inhibited the lymphocyte proliferation by LPS, ConA and PHA and NO production by LPS at non-cytotoxic concentrations (10-1000 ng/ml for splenocytes and 10-100 ng/ml for macrophages, respectively). These data suggest that karasurin-A has immunosuppressive activity in vitro.

Four new minor saponins, papyrioside LE-LH, were isolated from the leaves of Tetrapanax papyriferum, and their structures were determined on the basis of spectroscopic evidence.

In order to meet the increasing market needs for uncooled lasers for such applications as fiber- in-the-loop, high efficiency, high power, and highly reliable 1.3 micrometer uncooled InGaAsP/InP strained multi-quantum well Fabry-Perot lasers were fabricated with 50 mm wafer processing. Slope efficiency as high as 0.39 W/A and peak power as high as 46 mW at 85 degrees Celsius was obtained by optimizing the device structure for high temperature operation. We have also demonstrated excellent uniformity and reproducibility over 6 wafers. Reliability was also shown to be very good. More than 10,000 chips sites are available on a 50 mm wafer, and the cost is expected to be low. Because of the high performance, these lasers are expected to be used for various applications.

A mode-evolution-based polarization rotator-splitter built on InP substrate is proposed by combining a mode converter and an adiabatic asymmetric Y-coupler. The mode converter, consisting of a bi-level taper and a width taper, effectively converts the fundamental TM mode into the second order TE mode without changing the polarization of the fundamental TE mode. The following adiabatic asymmetric Y-coupler splits the fundamental and the second order TE modes and also converts the second order TE mode into the fundamental TE mode. A shallow etched structure is proposed for the width taper to enhance the polarization conversion efficiency. The device has a total length of 1350 µm, a polarization extinction ratio over 25 dB and an insertion loss below 0.5 dB both for TE and TM modes, over the wavelength range from 1528 to 1612 nm covering all C + L band. Because the device is designed based on mode evolution principle, it has a large fabrication tolerance. The insertion loss remains below 1 dB and the polarization extinction ratio remains over 17 dB with respect to a width variation of +/- 0.12 µm at the wavelength of 1570 nm, or +/- 0.08 µm over the entire C + L band.

By using propylamine as a connector, a dimer (L2) and trimer (L3) of 2,2':6',2''-terpyridine (tpy) are synthesized. They showed the lowest energy π–π* absorption at 354 nm and blue fluorescence at 420 nm with a moderate quantum yield in solution. Spectral titrations, electrospray ionization mass spectrometry (ESI-MS), (1)H–(1)H rotating-frame nuclear Overhauser effect correlation spectroscopy (ROESY), and structure simulation (MOPAC/PM5) indicated that both L2 and L3 form duplex-type multi-component complexes with Cd(II), [Cd(2)(L2)(2)](4+) and [Cd(3)(L3)(2)](6+), respectively. While the luminescence of these complexes was quite weak in solution (quantum yield Φ0.005), the complexes showed enhanced emission in the solid state with remarkable increase of the quantum yield (Φ = 0.13).

We discuss the potential of using coherently-coupled vertical cavity surface emitting laser arrays ashigh-intensity light sources. In particular, the design and performance of a novel two-dimensional phase-coupled grid Contact vertical cavity Surface Emitting Laser Array (C-SELA) is reported. We discuss theoptical properties of the C-SELA; in addition to the usual out-of-phase array mode, we demonstrate in-phase SELA coupling. We introduce a simple physical model to describe our experimental results. Over 1.2Watt optical power emission is obtained at room temperature from an electrically-excited lOxlO C-SELA.This laser array exhibited a low threshold current density of only 600Amps/cm2 and over 60% single-endeddifferential quantum efficiency. I . INTRODUCTION High power semiconductor lasers have a number of important commercial, medical, and military appli-cations.1'2 To date, little research has been conducted into the potential of using Vertical Cavity SurfaceEmitting Lasers (VCSELs) as a high intensity light source. The advantages of using VCSELs for highpower include ease of manufacture and testing of 2D arrays and thus low cost production, good optical pro-perties, and a buried active region beneath a distributed mirror, low surface power density due to increasedemission area and hence, the potential for low catastophic optical damage. We have studied variousapproaches to achieving large coherent output power from VCSELs.3 These include using a broad-areaemission window, a closely-spaced individually-pixellated VCSEL array, and a novel approach using a gridcontact to force coherence across the array by modulating the gain and reflectivity. We demonstrated highcoherent optical output power exceeding 0.53 W in a single coherent supermode from an 8x8 phase-coupledpatterned grid Contact vertical cavity Surface Emitting Laser Array (C-SELA).3 The C-SELA exhibits asmooth L-I and a low-voltage (1 .6V threshold voltage) electrical characteristic overcoming some of themajor problems associated with VCSELs. Another similarly-sized 8x8 SELA was studied in which all ele-ments were individually pixellated. In contrast to the C-SELA, it was found that the pixelated SELA,although exhibiting an extremely large external quantUm efficiency rj

We report on experimental studies of the nonlinear optical properties of nanocomposites consisting of organic (hyperbranched polymer)-metallic (Au or Pt) nanoparticle complex embedded in polymer films. Open-aperture and closed-aperture z-scan techniques are used to measure the effective third-order nonlinear optical susceptibilities χeff(3) of the composites under picosecond laser radiation at a wavelength of 532 nm. The relative sign of the real and imaginary parts of χeff(3) could be explained qualitatively by the Kramers–Kronig relation. We also determined the third-order nonlinear optical susceptibilities of Au and Pt nanoparticles estimated from the measured values for χeff(3) to be (−5.48+4.76i)×10−8 esu and (4.41−0.65i)×10−6 esu, respectively, at 532 nm with a help of the Maxwell–Garnett model.