A5044560248- Photonic and Optical Devices
- Optical Network Technologies
- Advanced Photonic Communication Systems
- Semiconductor Lasers and Optical Devices
- Photonic Crystals and Applications
- Advanced Fiber Laser Technologies
- Gut microbiota and health
- Phase-change materials and chalcogenides
- Spectroscopy and Quantum Chemical Studies
- Semiconductor Quantum Structures and Devices
- Laser-Matter Interactions and Applications
- Neural Networks and Reservoir Computing
- Silicon Nanostructures and Photoluminescence
- Advanced Optical Network Technologies
- Nonlinear Optical Materials Studies
- Nutritional Studies and Diet
- Clostridium difficile and Clostridium perfringens research
- Advanced Fiber Optic Sensors
- Diet and metabolism studies
- Photorefractive and Nonlinear Optics
- Computational Drug Discovery Methods
- Pharmacogenetics and Drug Metabolism
- Near-Field Optical Microscopy
- Integrated Circuits and Semiconductor Failure Analysis
- Adipose Tissue and Metabolism
National Institute of Advanced Industrial Science and Technology
2015-2024
National Institute of Biomedical Innovation, Health and Nutrition
2018-2024
Furukawa Electric (Japan)
2021
Keio University
2020
Yale University
2019
Sumitomo Dainippon Pharma (Japan)
1990-2017
Hamamatsu Photonics (Japan)
2012
Photonics Electronics Technology Research Association
2010-2011
Matsumoto Junior College
2009
Matsumoto University
2009
Abstract The gut microbiome is an important determinant in various diseases. Here we perform a cross-sectional study of Japanese adults and identify the Blautia genus, especially B. wexlerae , as commensal bacterium that inversely correlated with obesity type 2 diabetes mellitus. Oral administration to mice induce metabolic changes anti-inflammatory effects decrease both high-fat diet–induced diabetes. beneficial are unique amino-acid metabolism produce S-adenosylmethionine, acetylcholine, l...
We demonstrate a 32 × path-independent-insertion-loss optical path switch that integrates 1024 thermooptic Mach-Zehnder switches and 961 intersections on small, 11 25 mm2 die. The is fabricated 300-mm-diameter silicon-on-insulator wafer by complementary metal-oxide semiconductor-compatible process with advanced ArF immersion lithography. For reliable electrical packaging, the chip flip-chip bonded to ceramic interposer arranges electrodes in 0.5-mm pitch land grid array. on-chip loss...
We proposed and fabricated a current-driven phase-change optical gate switch using Ge2Sb2Te5 (GST225) thin film, an indium–tin-oxide (ITO) heater, Si waveguide. Microfabrication technology compatible with CMOS fabrication was used for the of The repetitive phase changing GST225 obtained by injecting current pulse into ITO heater beneath film. switching operation observed 100-ns 20 mA heater. average extinction ratio over wavelength range 1,525 to 1,625 nm 1.2 dB.
Predicting the fraction unbound in plasma provides a good understanding of pharmacokinetic properties drug to assist candidate selection early stages discovery. It is also an effective tool mitigate risk late-stage attrition and optimize further screening. In this study, we built silico prediction models human with freely available software, aiming specifically improve accuracy low value ranges. We employed several machine learning techniques trained on largest ever data set 2738...
We fabricate a 32 × silicon photonics switch on 300-mm silicon-on-insulator wafer by using our complementary metal-oxide-semiconductor pilot line equipped with an immersion ArF scanner and demonstrate average fiber-to-fiber insertion loss of 10.8 dB standard deviation 0.54 dB, on-chip electric power consumption 1.9 W. The the are approximately 1/60, less than 1/4 previous results, respectively. These significant improvements achieved design fabrication optimization waveguides intersections...
We report a multi-mode interference-based optical gate switch using Ge(2)Sb(2)Te(5) thin film with diameter of only 1 µm. The switching operation was demonstrated by laser pulse irradiation. This had very wide operating wavelength range 100 nm at around 1575 nm, an average extinction ratio 12.6 dB. Repetitive over 2,000 irradiation cycles also successfully demonstrated. In addition, self-holding characteristics were confirmed observing the dynamic responses, and rise fall times 130 ns 400...
We report on a path-independent insertion-loss (PILOSS) 8 × matrix switch based Si-wire waveguides, which has record-small footprint of 3.5 2.4 mm2. The PILOSS consists 64 thermooptic Mach-Zehnder (MZ) switches and 49 low-crosstalk intersections. Each the MZ intersections employs directional couplers, enable composition low loss switch. demonstrate successful switching digital-coherent 43-Gbps QPSK signal.
We demonstrate a record-high extinction-ratio of 50.4 dB in 2 × silicon Mach-Zehnder switch equipped with variable splitter as the front 3-dB splitter. The is adjusted to compensate for splitting-ratio mismatch between and rear splitters. high extinction ratio does not rely on waveguide crossings meets strong demand applications multiport circuit switches. Large fabrication tolerance will make compatible volume production standard complementary metal-oxide semiconductor facilities.
Autism spectrum disorder (ASD) is a complex group of clinically heterogeneous neurodevelopmental disorders with unclear etiology and pathogenesis. Genetic studies have identified numerous candidate genetic variants, including de novo mutated ASD-associated genes; however, the function these genes remains despite extensive bioinformatics resources. Accordingly, it not easy to assign priorities for further biological analysis. Here we developed convenient system identifying an experimental...
To increase the accuracy of microbiome data analysis, solving technical limitations existing sequencing machines is required. Quality trimming suggested to reduce effect progressive decrease in quality with increased length sequenced library. In this study, we examined thresholds (0-20 for QIIME1 and 0-30 QIIME2) on number reads that remained after control chimera removal (the good reads). We also distance analysis results gold standard using simulated samples.Quality abundance measurement...
A review is presented of femtosecond pulse-shaping methods and their application to spectroscopy atoms, molecules, condensed materials. Pulse shaping can be used generate pulse sequences other optical waveforms whose time-dependent amplitude, phase, frequency, polarization profiles are all specified precisely. The light-matter interaction mechanisms through which such for control over molecular material responses discussed. Most the spectroscopic experiments conducted date that involve...
We demonstrate a low-crosstalk 2 x thermo-optic switch with silicon wire waveguides. The device is based on array of Mach-Zehnder interferometer (MZI) switches. Lowest crosstalk levels -50 dB and -30 are obtained for 'bar' 'cross' switching states, respectively. An intersection in the important operation. power consumption one MZI element 40 mW total at most 160 mW.
We, for the first time, present ultrafast optical nonlinear response of a hydrogenated amorphous silicon (a-Si:H) wire waveguide using femtosecond pulses. We show cross-phase and cross-absorption modulations measured heterodyne pump-probe method estimate Kerr coefficient two-photon absorption waveguide. The pumping energy 0.8 eV is slightly lower than that required to achieve excitation at band gap a-Si:H (approximately 1.7 eV). An less 100 fs observed, which indicates free-carrier effect...
A precise flip-chip bonding (FCB) technology for indium phosphide semiconductor optical amplifiers (InP-SOAs) on a silicon photonics platform within less than ±1-μm alignment accuracy was developed. For efficient coupling and relaxed tolerance, the mode field both InP-SOAs Si waveguides expanded by spot-size converters (SSCs). On InP-SOAs, width-tapered SSCs were used to obtain an isotropic mode-field having approximately 3-μm diameter. platform, dual-core expand same size of 3 μm as SOAs....
We fabricated and characterized a silicon photonics 8 × strictly non-blocking optical switch based on double-Mach-Zehnder (MZ) element switches. The double-MZ switches, each of which consisted an intersection two asymmetric MZ enabled the suppression crosstalk across wide wavelength range. exhibited average fiber-to-fiber insertion loss 11.2 dB -20 in bandwidth wider than 30 nm. Furthermore, we constructed polarization-diversity by using switches demonstrated 32-Gbaud dual-polarization,...
We fabricate and characterize a polarization-diversity 32 × silicon photonics switch by newly introducing SiN overpass waveguides onto our nonduplicate path-independent insertion-loss switch. The are used to simplify the optical paths with uniform path length between edge couplers matrix significantly reduce number of waveguide intersections. chip is fabricated using 300-mm silicon-on-insulator wafer pilot line. comprises more than 7,600 components, making this largest ever...
We investigate nonlinear carrier dynamics in a multiquantum-well semiconductor optical amplifier (SOA) the context of ultrafast all-optical logic. A rate-equation model is presented that accounts for two-photon absorption, free-carrier self- and cross phase modulation, heating, spectral, spatial hole burning, polarization modulation. The refractive index investigated theoretically experimentally. find changes larger than /spl pi/ radians, which recovers on timescale order 1 ps. also AND gate...
We review the research progress of strictly nonblocking optical switches based on silicon photonics. have developed a switch chip fabrication process complementary metal-oxide-semiconductor pilot line and electrical packaging technologies. demonstrated all-paths transmission switching up to 32 input ports × output with an average fiber-to-fiber insertion loss 10.8 dB. Furthermore, we operating bandwidth wider than 100 nm for -30 dB crosstalk double-Mach-Zehnder element in 8 switch. For...
Abstract Atrial fibrillation (AF) reduces the quality of life by triggering stroke and heart failure. The association between AF onset gut metabolites suggests a causal relationship microbiota dysbiosis; however, remains poorly understood. We prospectively enrolled 34 hospitalized patients with 66 age-, sex-, comorbidity-matched control subjects without history AF. Gut microbial compositions were evaluated amplicon sequencing targeting 16S ribosomal RNA gene. assessed differences in dietary...
Inter-individual variations in gut microbiota composition are observed even among healthy populations. The may exhibit a unique depending on the country of origin and race individuals. To comprehensively understand link between host state, it is beneficial to conduct large-scale cohort studies. aim present study was elucidate integrated non-redundant factors associated with within Japanese population by 16S rRNA sequencing fecal samples questionnaire-based covariate analysis.A total 1596...
The gut microbiota is closely related to good health; thus, there have been extensive efforts dedicated improving health by controlling the microbial environment. Probiotics and prebiotics are being developed support a healthier intestinal However, much work remains be performed provide effective solutions overcome individual differences in community. This study examined importance of nutrients, other than dietary fiber, on survival bacteria high-health-conscious populations. We found that...
We developed a novel drug metabolism and pharmacokinetics (DMPK) analysis platform named DruMAP. This consists of database for DMPK parameters programs that can predict many based on the chemical structure compound. The DruMAP includes curated from public sources in-house experimental data obtained under standardized conditions; it also stores predicted produced by our prediction programs. Users several simultaneously compounds not found in database. Furthermore, highly flexible search...
To determine the region of human tumor necrosis factor-alpha (TNF-alpha), essential for cytotoxic activity against mouse L-M cells, single amino-acid-substituted TNF-alpha mutant proteins (muteins) were produced in Escherichia coli by protein engineering techniques. An expression plasmid was mutagenized passage through an E. mutD5 mutator strain and oligonucleotide-directed mutagenesis. Approximately 100 muteins assayed activity. The activities purified muteins, e.g. TNF-31T, -32Y, -82D,...
An optical gate switch using Ge2Sb2Te5 phase-change material integrated with a silicon waveguide is reported. The very small (∼2 µm) owing to the large difference in absorption coefficient between crystalline state and amorphous state. prototype has been fabricated successfully switched from transparent on-state opaque off-state by laser pulse irradiation. extinction ratio of more than 12.5 dB was achieved over wavelength range 75 nm.