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We propose a high-capacity polymer-based optical and electrical LSI package integrated with multimode Si photonic transmitters and receivers. We describe the fabrication and characteristics of the polymer-based hybrid LSI package substrate with a polymer optical waveguide, a mirror, and optical card edge connectors. We fabricated optical mirrors with several angles ranging from 40° to 45° for the Si photonic grating coupler by using a dicing blade at an angle. The dicing mirror changed the emission angle for the grating coupler. We also realized a large lateral misalignment tolerance (±11.5 μm) between the polymer waveguide and MMF for 1 dB of excess loss at 24 channels. We obtained 1-dB coupling loss using an optical card edge connector at 1.3 μm because of the large tolerance. We realized 25-Gb/s error-free transmission per channel at 1.3 μm. We also describe here the error penalty and jitter due to modal noise generated by coupling mismatch.

Efficient, broadband, and polarization-independent optical input/output (I/O) coupling of silicon photonics chips is significant for its practical application, and single-mode vertical optical I/O coupling will be necessary for high-density optical I/O connections required in future high-performance computing systems. We demonstrated such optical coupling using a 45° mirror, which was integrated by a cost-effective dicing technique with a polishing process. The 45° mirrors were integrated into Si-rich silica (SiOx) waveguides on a Si substrate. To evaluate the light beam profile, which was important factor for the single-mode optical coupling, we measured near field patterns and far field patterns of light beams reflected by the 45° mirror. Owing to the polishing process, high-quality single-mode beams were successfully obtained as the vertical optical output. Using the fabricated 45° mirrors, the efficient single-mode vertical optical coupling with loss penalty of around 0.3 dB was demonstrated. The wavelength-dependent loss was less than 0.6 and 0.2 dB for TE and TM polarization, respectively. The polarization-dependent loss was also very small and it was less than 0.2 dB in 1500–1600 nm.

We propose a polymer-based optical and electrical hybrid LSI package integrated with silicon photonic chips. We fabricated hybrid package substrate with polymer optical waveguide and card edge connector. We realized a 25-Gbps per channel error-free transmission at 1.3-µm.

Efficient vertical optical coupling of a silicon photonics chip was demonstrated with Si integrated 45 degree mirror. Additional coupling loss was around 1.2 dB over broadband wavelength of 1450–1650 nm for TE/TM polarization.

Benzoate X receptor (BXR) is a member of the nuclear hormone receptor superfamily and is activated by alkyl esters of amino benzoic acids and expressed during early development stages. We report here a second BXR, which was cloned by screening Xenopus laevis embryonic cDNA libraries. This new BXR, termed BXRβ, exhibits 97% identity in the DNA-binding domain and 79% identity in the ligand-binding domain in amino acid sequence to previously reported Xenopus BXR. The BXRβ strongly binds as a heterodimer with retinoid X receptor (RXR) to direct repeats of an AGGTCA motif spaced 4 or 5 base pairs apart and activates transcription by addition of methyprednisolone and dexamethasone as well as amino- and hydroxybenzoates.

In order to establish a national reference system for Campylobacter serotyping in Japan, 7 local institutes of public health collaborated to prepare 30 serogrouping antisera including 26 antisera of Lior's serogrouping system and 4 antisera of TCK serogrouping system which was developed by the Tokyo Metropolitan Research Laboratory of Public Health. A total of 603 strains (92.2%) out of 654 isolates from 23 outbreaks of C. jejuni throughout Japan were serogrouped by the 30 antisera. Out of 1,198 strain isolated from sporadic cases of Camplyobacter gastroenteritis, 883 (73.7%) were typed and 298 strains (24.9%) were untypable. The remaining 17 strains belong to rough form were not used for serogrouping. A hundred thirteen out of 883 strains have reacted with more than one typing serum. Among C. jejuni isolated from 7 prefecture, Lior's serogroup 4 was most common followed by Lior's serogroup 4, 2, 11, 1 and TCK serogroup 1 and 12. We conclude from the experiment described above that this Lior's serogrouping system by combining with TCK serogroup for Campylobacter jejuni/coli is useful in epidemiological investigations in Japan.

The susceptibilities of 100 clinical isolates of Campylobacter jejuni to rokitamycin, a new macrolide, and eight other oral antibiotics were tested by using a broth microdilution method. Rokitamycin demonstrated antibacterial activity that was higher than those of fosfomycin and the tetracyclines and comparable to those of erythromycin and clindamycin, whereas it was slightly less active than the quinolones.

The present survey was undertaken to investigate the distribution of enteropathogenic E. coli (EEC) in oyster-farm areas in Hiroshima Bay and to investigate the correlation between food-poisoning outbreaks due to raw oysters and EEC.A total of 550 samples, including sea water (188), raw oysters (236), river water (72) and bay mud (54), was collected and examined during the winters from Dec. 1969 to Jun. 1979.The results obtained can be summarized as follows:1) The isolation rate of EEC was 14.0% (33/236) in raw oysters, 14.4% (27/188) in sea water, 15.3% (11/72) in river water and 3.7% (2/54) in bay mud.2) The isolates were classified into twenty serotypes. The distribution frequencies were O128:K67 (21/84), O125:K70 (8/84), O127:K67 (7/84), O44:K74 (6/84) and O26:K60, O55:K59, O28:K73, O126:K71 (5/84).3) Two serotypes of EEC were isolated at the same time from four samples each of oysters and sea water, and three serotypes of EEC from one sample of sea water.4) In raw oysters and sea water there appeared to be a relationship between the amount of E. coli and the incidence of EEC.The incidence of EEC-positive samples was slighly higher (p=0.05) in samples with E. coli MPN>230 compared to ≤230 in oysters and higher (p=0.01) in samples with >18 compared to ≤18 in sea water.These results show that EEC is widely distributed at oyster-farm area in Hiroshima Bay, and suggest that some cases of food poisoning due to raw oysters can be attributed to the eating of raw oysters contaminated with EEC.