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This paper reviews our recent device design activities on wavelength splitters/combiners. We start with blind optimization of MMIs having rectangular patches, and then based on the physical insight, the device structures are simplified to achieve even better performance. This methodology is applied to low insertion loss for two- and four-wavelength splitters/combiners, and it can be applied to other types of devices.

Background: In chronic respiratory diseases, it is difficult to evaluate daily exercise tolerance, physical activity and profile of oxygenation. While those evaluations are important to maintain their QOLs, those studies have not been fully performed except COPD. Aims & Methods: To investigate a predictor of daily activity and near respiratory failure in outpatient routine practice, we evaluated 4-meter gait speed (4MGS), 6MWD and pulmonary function testing in our outpatient clinic, and 24-hour pulse oximetry monitoring, daytime step counts and duration of physical activity by using electronic accelerometer in community-living 24 patients with stable chronic respiratory diseases (interstitial pneumonia 17 patients, COPD 4, CPFE 3, respectively) not receiving supplemental oxygen. We analyzed the relationship among the values. Results: The mean PaO 2 at rest was 81.9 Torr ranged from 63.3 to 95.4 Torr. The daily step counts and duration of activity time were strongly correlated with %FEV 1 (p=0.001), and the step counts were correlated with 4MGS, 6MWD (p=0.034, p=0.039, respectively). The mean %diurnal time with SpO 2 2 Conclusion: %FEV 1 , 4MGS and 6MWD were useful to detect daily activity level. This study also suggested that patients with near chronic respiratory failure reduce their daily physical activity to avoid the oxygen de-saturation without awareness. We need to predict their daily activity by testing 4MGS and 6MWD with measuring SpO 2 ,even if SpO 2 >90% at rest and on ambulatory pulse oximetry monitoring in their daily life.

We investigate the nonlinear performance of 8QAM-alternative 4D modulation format using GMI to evaluate the BICM capacity. Due to its constant modulus feature, the 4D-2A8PSK modulation has higher nonlinear threshold than Star-8QAM and Circular-8QAM.

We investigate the impact of laser frequency drift, which can cause inter-channel interference (ICI) in superchannel communications. We show that Han-Kobayashi coding significantly improves robustness against the drift, achieving 2-times higher achievable rate than conventional coding.

10 km transmission with 53.2 Gb/s NRZ format was demonstrated using 1310 nm high speed EML device. Evaluated dispersion penalty and receiver sensitivity show enough capability of NRZ format for 400 Gb/s Ethernet applications up to 10 km link.

We propose a simplified strategy for Han-Kobayashi coding to handle inter-channel interference in optical superchannels. The proposed scheme achieves higher than Tb/s data rates while the complexity for superposition coding is avoided.

We propose a dynamic window decoding scheme for LDPC convolutional codes to reduce the latency compared to the belief propagation decoding. The BER performance of our proposed memory-efficient decoding scheme is verified by simulations.

We propose new trellis-coded high-dimensional modulation robust to polarization crosstalk in coherent optical communications. Since the modulation can automatically recover polarization crosstalk, it offers 2 dBQ improvement with blind equalization.

We experimentally examine the maximum achievable transmission performance of a 7 channel Nyquist-WDM system with 10GBd per carrier. Back-to-back, a maximum of 11.9 bit/sym and 13.8 bit/sym can be transmitted for DP-64QAM and DP-256QAM respectively, while after 2 spans of transmission, a maximum of 12.4 bit/sym and 11.6 bit/sym can be achieved.

We propose a new high-dimensional modulation (HDM) format, based on the Nordstrom-Robinson code, which is the best-known nonlinear block code in 16 dimensions. With EXIT chart, we optimize LDPC codes for various HDM formats, and show their benefits.

We propose a compact MMI-based 4-beam combiner with a spline-curved index step. The 1.74mm-long device designed in InP material systems offers 3dB better transmittance than power combiners at a 4.5 nm wavelength spacing.

We propose a modified log-likelihood ratio (LLR) calculation for an LDPC decoder to be robust against residual phase noise at the demodulator. The proposed scheme is based on a linear/bilinear transform offers 1 ∼ 2dB gain in the presence of large phase noise.

We show how to design capacity-approaching LDPC codes under different modulation formats and different decoding methods. With EXIT chart analysis for finite-iteration BICM-ID of various HDM, we achieve 2dB gain from a code optimized for 1D modulation.

An MMI-based polarization splitter/combiner with a TE-TM splitting ratio above 15 dB over a 21 nm wavelength range is demonstrated. The compact device is integrated in a photonic circuit within an InP multi-project wafer run.

We show a great potential of nonbinary (NB) LDPC convolutional codes in low- latency decoding for HDM. We show that NB-LDPC can provide considerable performance improvement compared to conventional BICM-ID, which requires soft-decision feedback.

We propose a novel low complexity CPE algorithm that uses pilot symbols and inference for estimating carrier phase in single carrier systems. Performance is validated by simulation of 64QAM over the range of SNRs for which 64QAM is optimal for BICM.

We proposed a method of measuring the intrinsic linewidth of semiconductor lasers, by using self-heterodyne method with multiple measurements of different delay fiber lengths. By eliminating the 1/ f noise effects, the linewidth becomes much smaller than the conventional measurement method.

Ni(acac) 2 catalyzes the four-component connection reaction of diphenylzinc, isoprene, aromatic aldehydes, and aromatic amines in this order and provides stereochemically homogeneous ( E )-1-arylamino-1-aryl-3-methyl-5-phenyl-3-pentenes ( 1 ) in excellent yields. Aliphatic aldehydes react similarly and give ( E )-1-arylamino-1-alkyl-3-methyl-5-phenyl-3-pentenes ( 1 ) in slightly reduced yields. When the alkyl groups are bulky, in addition to 1 are formed ( E )-1-arylamino-1-alkyl- 4 - methyl -5-phenyl-3-pentenes ( 1′ ) as the minor products. Lactamines prepared in situ from five- and six-membered lactols and aromatic amines are more reactive than alkyl aldehyde aldimines and furnish ( E )-4-arylamino-6-methyl-8-phenyl-6-octen-1-ols ( 4 ) and ( E )-5-arylamino-7-methyl-9- phenyl-7-nonen-1-ols ( 5 ), respectively, in good yields with excellent E -stereoselectivity.

Introduction: Cardiovascular mortality in patients with lower limb artery disease is higher in critical limb ischemia (CLI) than in intermittent claudication (IC). We sought to evaluate differential characteristics of coronary artery disease severity and prognostic factors for cardiovascular events between CLI and IC patients. Methods: Coronary and lower limb angiography was performed on 242 patients (age 73±8 years, mean±sd, men 186) without cardiac symptoms and with symptoms of either CLI or IC. From the coronary angiogram of each study patient, Gensini Score as an index of coronary angiographic severity and an incidence of significant stenosis (AHA classification, ≥75% stenosis) in at least one of major coronary arteries were evaluated. High sensitivity troponin T (hs-TnT), eicosapentaenoic acid-arachidonic acid ratio (EPA/AA), and lipoprotein (a), as biomarkers for prognostic factors, were measured from blood samples at rest in the fasting state. Results: The study patients were divided into CLI-group (42 patients) and IC-group (200 patients). Coronary angiography showed that Gensini Score and an incidence of significant stenosis (AHA classification, ≥75% stenosis) in at least one of major coronary arteries were higher in the CLI-group than in the IC-group (39±32 vs 8±8, p Conclusions: Greater coronary artery disease severity, higher hs-TnT and lipoprotein (a), and lower EPA/AA were observed in the CLI patients, which may explain higher cardiovascular events in CLI patients than IC.

Background: Recent studies have reported several types of neointimal tissues including neoatherosclerotic progression in stent restenosis. However, the influence of neointimal tissue characteristics on outcomes after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR) remains unclear. Periprocedural myocardial infarction (PMI) is related to poor outcomes after PCI. We assessed relationships neointimal tissue characteristics and occurrence of PMI after PCI in ISR lesions. Methods: We investigated 45 ISR lesions in 45 stable angina pectoris (SAP) patients who underwent pre- and post-PCI coronary angioscopy (CAS) and optical coherence tomography (OCT) examination. We excluded patients with hemodialysis. All lesions were divided into lesions with PMI, defined as high-sensitivity cardiac troponin-T (hs-cTnT) values after PCI ≥5 times of the upper reference limit in patients with normal baseline values or ≥5 times of baseline values if hs-cTnT values were elevated before PCI, and those without. Clinical and lesion characteristics including intrastent neointimal tissues were compared between two groups. Results: PMI was observed in 15 (33.3%) lesions. Clinical characteristics including stent types and terms after stenting were similar between lesions with and without PMI. CAS analysis showed higher frequency of white neointimal proliferation with irregular surface or yellow neointima at the culprit site before PCI (86.7% vs. 43.3%, p=0.009) and atheromatous appearance (CAS-AP), defined as yellow plaque including complex thrombi underneath disrupted neointimal coverage after ballooning (66.7% vs. 16.7%, p=0.003) in lesions with PMI than those without. OCT analysis demonstrated higher frequency of heterogeneous neointima or neointimal thin-cap fibroatheroma in lesions with PMI (73.3% vs. 33.3%, p=0.02). Multivariate analysis including clinical and lesion characteristics and procedural results showed CAS-AP as an independent predictor for occurrence of PMI (odds ratio:6.90, 95% CI:1.68-28.41, p=0.008). Conclusions: In ISR lesions with SAP patients, the assessment of neointimal tissue characteristics by using CAS and OCT images may be useful for the prediction of occurrence of PMI.

Background: Several studies have reported that echo-attenuated plaque (EA) on intravascular ultrasound (IVUS) was related to poor outcomes after percutaneous coronary intervention (PCI) in acute coronary syndrome. However, its clinical significance and influence on outcomes in patients with stable angina pectoris (SAP) has not been fully clarified. We investigated relationships of EA on IVUS with other plaque morphologies and outcomes after PCI in SAP patients. Methods: We investigated 127 de-novo lesions in 127 SAP patients with normal pre-PCI cardiac troponin-T level (cTnT Results: EA was observed in 34 (26.8%) lesions. Lesions with EA had greater vessel area (15.8±4.9 vs. 12.7±4.0 mm2, p=0.002), plaque burden (83.9±7.2 vs. 78.6±8.6%, p Conclusions: In SAP lesions, presence of EA on IVUS may suggest the existence of unstable plaque compositions and may predict for occurrence of PMI.

Polymer enhanced oil recovery (EOR) operation has been implemented for the production of oil from difficult mature oilfields in Oman. The polymer used in this EOR technique to sweep oil toward production wells is resulting in the generation of polymer flood produced water (PFPW) of increasing viscosity. Current methods of treating oilfield produced water must be reconsidered for the effective treatment of such PFPW of changing quality. In a previous study, the utilization of polyaluminum chloride (PAC) chemical was proposed for the coagulation of oil in produced water to be separated by flotation and filtration. As such, laboratory tests were conducted to evaluate the applicability of PAC and other chemicals for treatment of PFPW that has higher viscosity than ordinary oilfield produced water. These tests clearly indicated that aluminum sulfate (AS) chemical was more effective for treatment of such higher viscosity water. A pilot plant developed during the earlier study, was utilized to conduct coagulation/flocculation, flotation, filtration, and adsorption treatment trials for PFPW from an oilfield where polymer EOR is underway. For the final trial, the inlet PFPW viscosity was 1.4 cP at 40 °C and oil concentration was above 200 mg·L−1. AS was applied for coagulation/flocculation and flotation stages, and was found to be effective in reducing oil concentration to 1 mg·L−1. Filtration and adsorption stages resulted in further improvement of water quality. Most of the polymer used for EOR was believed to have been removed along with oil and suspended solids.

Objective: A randomized, crossover, double-blinded placebo-controlled and non-blinded active drug-controlled, comparative clinical trial was conducted to evaluate the efficacy and safety of sublingual fentanyl tablet. Methods: Subjects were patients treated with strong opioids at fixed intervals for chronic cancer pain and with oral morphine as rescue medication for breakthrough pain. Sublingual fentanyl was administered at doses that were 1/25th (high dose) and 1/50th (low dose) of the dose of rescue morphine and was compared with placebo and oral morphine. The primary endpoint was pain intensity difference at 30 min after administration. (Clinical Trials Government; NCT00684632). Results: Fifty-one patients were enrolled in the investigation. Their mean pain intensity in visual analog scale before rescue medication prior to the investigation was 60.96 (16.44, standard deviation) mm. Compared with placebo, the low and high doses of sublingual fentanyl showed significant analgesic effects (least squares mean difference, 4.54 and 8.49 mm; P= 0.014, P< 0.001, respectively). Adverse reactions were observed in 17.6%, the most common being constipation, nausea and somnolence. The incidence of adverse reactions during the high-dose administration period was higher than that during the low-dose and active control drug administration periods. Conclusions: Patients treated with strong opioid analgesics at fixed intervals for chronic cancer pain and with oral morphine at doses up to 20 mg as rescue medication were investigated. The doses of sublingual fentanyl to treat breakthrough pain were determined from rescue morphine doses by use ofconversion ratios.In thesepatients,administration of sublingualfentanyl atdoses determinedbya conversion ratio of 1/50 was effective and safe. Further studies are needed to validate the use of this conversion method.

Angiosarcoma in the lung is an uncommon disorder and is usually attributable to metastasis from a primary site. Primary pulmonary angiosarcoma is extremely rare, and the prognosis of affected individuals is dismal, with most patients dying within months of presentation. Indeed, there have been no reported instances of successful treatment of this condition. We now report the case of a patient with primary pulmonary angiosarcoma who responded to a combination of radiotherapy and immunotherapy with recombinant interleukin-2. The patient remains well without signs of recurrence 1 year after initial presentation. This combination therapy may be a promising strategy to prolong the survival of patients with primary pulmonary angiosarcoma.

Semiconductor lasers with narrow far fields are highly desirable because they can be directly coupled to fiber with high-coupling efficiency, eliminating the cost of lenses and extra packaging. Because of their smaller size, they facilitate more compact transmitters, and since they can be used unpackaged, they enable complex integrated optoelectronic devices. We describe the design, fabrication, and performance characteristics of our family of spot-size-converted (SSC) devices with narrow far fields designed for directly modulated (2.5 and 10 Gb/s) uncooled (85/spl deg/C) use. The design consists of a conventional active region buried heterostructure laser coupled to an expander region (consisting of a loosely confining waveguide) through a laterally tapered etch of the active layers. This basic design achieves far fields of /spl sim/16/spl times/10 degrees, suitable for coupling /spl sim/50 percent of the emitted light into a flat cleaved fiber. Distributed feedback (DFB) 1.3- and 1.5-/spl mu/m devices, and 1.3-/spl mu/m Fabry-Perot (F-P) lasers have been implemented in this technology. The devices have dc thresholds from 8-12 mA at 25/spl deg/C and 35-45 mA at 85/spl deg/C, with peak power of >15 mWs over temperature, all similar to non-SSC devices with the same active regions. Both SSC F-Ps and DFBs demonstrate bandwidths of >7 GHz and wide-open eyes at 85/spl deg/C, and reliability suitable for uncooled use. With the DFB device, we also demonstrate a wide open 10-Gb/s eye pattern at room temperature. The laser on a submount demonstrates coupling to a fiber in a v-groove of /spl sim/25% using passive alignment, and sufficient tolerance to back reflection to enable transmission over at least 15 km with typical drive circuitry. Analysis shows that these lasers also have a factor of two improvements in alignment tolerance compared to standard devices in a typical lensed system. The expander impacts the dc and dynamic characteristics of the SSC F-P through the increase in cavity size. The dc and dynamic characteristics of SSC DFBs and standard DFBs are very similar, demonstrating that expander-related absorption and mode transition loss has been almost eliminated in this structure. The SSC-DFBs are, thus, the preferred device for high-speed applications. To our knowledge, the 1.3-/spl mu/m lasers described are the first SSC devices fully suited for use as an uncooled 2.5-Gb/s transmitters up to 85/spl deg/C. The combination of a tailored narrow far field with an edge emitting structure rivals vertical cavity lasers in alignment tolerance for low-cost packaging with superior dynamic and thermal performance.

地域の地震被害予測に際し, 対象領域のS波速度, Q値, 層厚および密度などの構造を的確に評価することは最重要項目の一つである. 本研究では, はじめに福井大学の鉛直アレイ, ならびに福井平野の東西軸に沿って展開した地震計によって観測された強震記録の周波数特性ならびにH/Vスペクトル特性を提示し, その地盤条件との関連を検討した. ついで, 観測地震動と対応する重複反射法による計算値を周波数領域で比較し, 両者の誤差自乗和を最小化することにより, 観測点直下の層厚およびQ値を推定する逆解析手法を定式化した. 本手法を, 福井地域で得られた多数の地震観測記録に適用し, 福井平野の東西方向断面の地下構造を推定するとともに, 弾性波探査結果などと比較・検討した. 推定された地盤構造によって, 観測地震動が精度良く再現しうること, 推定された福井平野の地盤構造は, 既存の資料と矛盾が少ないことなどを確認した. 提案する地盤構造推定手法を, 強震動観測点に順次適用するとともに, 既存資料および微動観測などを補間情報として活用することにより, 地域の3次元的な地盤構造を, 比較的高精度で推定できる可能性があり, 地震被害予測の精度の向上が期待できるものと考えられる.

Pancratistatin derivatives, 1-O-(3-hydroxybutyryl)pancratistatin (HBP) and 1-O-(3-O-beta-D-glucopyranosylbutyryl)pancratistatin (GBP), showed strong cytostatic activity against rat embryo fibroblast 3Y1 at concentrations less than 1 microM. When the effect on cell cycle progression was examined in 3Y1 fibroblasts arrested at G0/G1 phase by serum deprivation, HBP, GBP, and pancratistatin inhibited the progression of 3Y1 fibroblasts from G0/G1 to S phase. In addition, when the effect on cell cycle progression was studied in 3Y1 fibroblasts synchronized at late G1/early S phases by treating with hydroxyurea, HBP blocked further progression through S phase, while GBP and pancratistatin did not affect the progression, but retarded it. On the other hand, when the effect of HBP and GBP on the progression was evaluated in promyelocytic leukemia HL-60RG cells synchronized at G0/G1 phase, the cells did not progress into S phase and accumulated in sub G0/G1 phase, which indicated apoptotic cells. These findings suggest that of Amaryllidaceae alkaloids, HBP blocks the progression of cell cycle at least at G0/G1 and S phases and GBP does at least at G0/G1 phase, resulting in apoptosis induction in tumor cells.

Perioperative corticosteroid supplementation is generally applied in patients with primary adrenal insufficiency or treated with long-term corticosteroid. Currently, appropriate dose and timing of corticosteroid were revised. A 77-year-old woman with primary adrenal insufficiency underwent transurethral resection of bladder tumor (operation 1) and mastectomy (operation 2). In both operations, we supplied stress dose of hydrocortisone on the operative day (100 mg x day(-1) of hydrocortisone for operation 1 or 300 mg x day(-1) of hydrocortisone for operation 2) and decreased gradually in one day (operation 1) or in three days (operation 2), respectively. No remarkable symptoms of adrenal deficiency and side effects of corticosteroid during perioperative period were observed. According to current recommendation, the dose of corticosteroid we used could be smaller. Perioperative management of adrenal insufficiency is still controversial, and further investigation is necessary.

Gold nanoparticles (1 nm in size) stabilized by ammonium salts of hyperbranched polystyrene are prepared. Selection of the R groups provides access to both water- and organo-dispersible gold nanoparticles. The resulting gold nanoparticles are subjected to studies on catalysis in solution, which include reduction of 4-nitrophenol with sodium borohydride, aerobic oxidation of alcohols, and homocoupling of phenylboronic acid. In the reduction of 4-nitrophenol, the catalytic activity is clearly dependent on the size of the gold nanoparticles. For the aerobic oxidation of alcohols, two types of biphasic oxidation are achieved: one is the catalyst dispersing in the aqueous phase, whereas the other is in the organic phase. The catalysts are reusable more than four times without loss of the catalytic activity. Selective synthesis of biphenyl is achieved by the homocoupling of phenylboronic acid catalyzed by organo-dispersible gold nanoparticles.

A novel wavelength combiner using non-uniform refractive index distribution within a multimode interference device is proposed and simulated. The refractive index step creates separate localized modes with different effective refractive indices and two modes are strongly excited which form the basis of an interferometer. We applied the concept to 1.30/1.31 μm and 1.31/1.55 μm wavelength combiners on an InP substrate. The lengths of the devices are 1272 μm and 484 μm with simulated insertion losses of 0.6 dB and 0.67 dB respectively.

We explore high-dimensional modulation for mode-division multiplexed optical fiber communication systems, focusing on optimized 24-D modulation formats in six-mode fiber transmission. Compared with conventional formats, our simulations demonstrate up to 8.7 dB span loss budget improvement for 6 b/s/Hz intra-channel spectral efficiency.

A 67-year-old man suffering from esophageal cancer was admitted to our hospital complaining of dyspnea and hypoxemia. He had been treated with cisplatin, docetaxel, and fluorouracil combined with radiotherapy. Chest computed tomography revealed bilateral ground-glass opacity, and bronchoalveolar lavage fluid showed increased eosinophils. Two episodes of transient eosinophilia in peripheral blood were observed after serial administration of anticancer drugs before the admission, and drug-induced lymphocyte stimulation test to cisplatin was positive. Thus cisplatin-induced eosinophilic pneumonia was suspected, and corticosteroid was effectively administered. To our knowledge, this is the first reported case of cisplatin-induced eosinophilic pneumonia.

We show that an iterative demodulation with soft-decision feedback information from FEC decoder can efficiently mitigate cycle slips. With 3% pilot insertion, the turbo QPSK demodulation achieves 1.05 dB gain even in the presence of frequent cycle slips.

A novel wavelength combiner using a refractive index step within a multimode interference device is proposed and simulated. An InP-based 1.30/1.31 μm combiner has a length of 1272 μm and an insertion loss of 0.6 dB.

We experimentally demonstrate ultra-long haul transmission of 24-D extended Golay coded modulation with LDPC. Compared with LDPC coded DP-BPSK, an increase of 15% in reach was shown, with a 3 dB increase in launch power margin at a transmission distance of more than 16,000 km.

Nine novel prenyl-dihydrofurocoumarin-type sesquiterpenoid derivatives, 2, 3-dihydro-7-hydroxy-2R*, 3R*-dimethyl-2-[4, 8-dimethyl-3(E), 7-nonadienyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-hydroxy-2S*, 3R*-dimethyl-2-[4, 8-dimethyl-3(E), 7-nonadien-6-onyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-hydroxy-2S*, 3R*-dimethyl-2-[4-methyl-5-(4-methyl-2-furyl)-3(E)-pentenyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-hydroxy-2R*, 3R*-dimethyl-2-[4-methyl-5-(4-methyl-2-furyl)-3(E)-pentenyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-methoxy-2S*, 3R*-dimethyl-2-[4, 8-dimethyl-3(E), 7-nonadienyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-methoxy-2R*, 3R*-dimethyl-2-[4, 8-dimethyl-3(E), 7-nonadienyl]-furo[3, 2-c]coumarin, 2, 3-dihydro-7-methoxy-2S*, 3R*-dimethyl-2-[4, 8-dimethyl-3(E), 7-nonadien-6-onyl]-furo-[3, 2-c]coumarin, and 2, 3-dihydro-7-methoxy-2S*, 3R*-dimethyl-2-[4-methyl-5-(4-methyl-2-furyl)-3(E)-pentenyl]-furo[3, 2-c]coumarin, were isolated from the roots of Ferula ferulioides. The structures were established by comprehensive spectral analysis. The biosynthetic pathway leading to these prenyl-furocoumarin-type sesquiterpenoids is proposed based on their structures.