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Background: Thin delivery system stents can be inserted directly without the need for a tract dilation step and are expected to reduce bile leakage during endoscopic ultrasound-guided biliary drainage (EUS-BD). The present study retrospectively compared the safety and efficacy of EUS-BD using a thin metal stent (< 7.5 Fr) with those of EUS-BD using a conventional stent (≥ 7.5 Fr). Methods: The present study enrolled 112 patients who underwent EUS-BD using metal stents for unresectable malignant biliary obstruction between April 2016 and July 2022. The primary endpoint was the rate of adverse events (AEs). The secondary endpoints were clinical success rate, procedure time, procedure success rate in the absence of the tract dilation step, recurrent biliary obstruction rate, time to biliary obstruction, and overall survival. Risk factors associated with early AEs were also evaluated. Results: The rate of early AEs was significantly lower (12% vs.35%, P= 0.013) and the procedure success without the tract dilation step was significantly higher (82% vs.33%, P< 0.001) in the thin than in the conventional delivery system stent group. None of the other secondary endpoints differed significantly between the two groups. Multivariate analysis showed that employing the tract dilation step during EUS-BD was a significant independent risk factor for early AEs (skipping vs.employing; HR, 9.66; 95% CI, 1.13–83.0, P= 0.028). Conclusion: Employing the tract dilation step during EUS-BD was a significant risk factor for early AEs. Metal stents with a delivery diameter < 7.5 Fr can be inserted directly without the tract dilation step, resulting in lower early AE rates.

Recently, the organic polymer films attract attention as promising dielectric films which reduce environmental burdens and inhibit RC-delays. It is very important to understand its mechanical properties. In the previous studies, we could evaluate its reliability by measuring the interfacial energy release rates during the peeling under various conditions. So in this study, we applied this method to several types of specimens. Then, the phase angle effect on interfacial toughness and its contributions were considered by analyzing the results. In addition, we derived fracture criterion in order to feed back to manufacturing process. SiLK (trademark of the Dow Chemical Company) was selected as dielectric material. We prepared two types of specimens. One consists of spin-coated SiLK layer sandwiched between Si substrates using adhesion bond (adhesion bond specimen). The other is made by the following process; at first, two Si substrates with spin-coated SiLK were swelled in solvent. Then, their SiLK faces were pressured and heat cured in oven (thermal pressure bond specimen). Four points bending and DCB tests were performed. Crack path was identified using SEM observation and ESCA analysis in addition to the mechanical test. From the results under different mode mixty condition, the existence of phase angle effect on facial fracture toughness was studied out. Its primary factors were due to bridging of SiLK layer and plastic deformation of SiLK layer and/or adhesion bond layer. Moreover, we evaluated the fracture criteria under several conditions using an ellipse approximation.

We investigate the cause of the insertion loss of our holographic switch by determining the relation between the diffraction efficiency and the hologram patterns generated by the control beams. According to the calculation the theoretical insertion loss is 7.4 dB with loss distribution of 0.03 dB under the conditions of a previous experiment. We find that incomplete storage of the interference pattern on the optically addressed spatial light modulator is the strongest factor determining the insertion loss.

We have proposed a holographic switch with a ferroelectric liquid-crystal spatial light modulator for a large-scale switch. 4 × 1204 switching was demonstrated to show that the proposed switch structure is suitable for a large-scale switch. The average losses of the four inputs were 28, 33, 35, and 36 dB. The average crosstalk-to-signal ratio of one of the inputs was-16 dB.

We extended the scale of a previously reported holographic switch [Appl. Opt.34, 8137 (1995)] in which each input is assigned to one of the control light sources to control a large-scale switch with low power. The average losses of the four inputs were 28, 33, 35, and 36 dB. The average cross-talk-to-signal ratio of one of the inputs was -16 dB.

Simulating the positions of output beams under the assumption that a liquid-crystal display acts as a binary phase modulator reveals that the number of the outputs increases almost linearly with the square root of the number of pixels assigned to an input. This result is confirmed by experiments, and it is estimated that 1016 outputs can be obtained when the number of pixels is 700 × 700. Holographic switches with liquid-crystal displays are therefore suitable for large-scale switches.

A holographic switch with a ferroelectric liquid-crystal spatial light modulator is proposed for large switching systems such as those used in subscriber networks. Preliminary experiments have achieved a one-input, 48-output switch. The relationship between the power of the control-light source and the number of outputs is calculated; the results agree well with the experiment. The calculation suggests that 10384-output switching can be obtained with a 25-mW control-light source. It should therefore be possible to control a large-scale switch with low-power control-light sources.

The subgroup characteristics of 130 strains of respiratory syncytial virus (RSV) isolated in Sapporo during 9 epidemic years 1980-1989 were determined. Monoclonal antibodies raised against the RSV Long strains were used. Subgroup A included 77 (59.2%) isolates and subgroup B 52 (40.0%) strains, while 1 strain was considered to be a variant of a subgroup A strain. The distribution by age of infants and children was different for the 2 subgroups: < 1 year of age infants with subgroup A infection dominated, > 1 year of age subgroup A infections were less common than subgroup B infections. These was no difference in type of illness between the subgroups. Bronchiolitis was the dominant diagnosis in all patients.

A new configuration of holographic switches is proposed and verified for multichannel optical switching. Experimental 1 × 64 and 2 × 32 switching is achieved by using real-time binary phase-only holograms generated by a twisted nematic liquid-crystal display. This holographic free-space switching is applicable to photonic switching systems and optical interconnections.

Experimental 4 × 4 free-space optical switching is successfully demonstrated by real-time binary phase-only holograms. The real-time holograms are generated by a twisted nematic liquid-crystal display, which is a binary phase-only modulator. This holographic free-space switching is applicable to optical interconnections and photonic switching systems.

We demonstrate 1 × 1104 holographic switching with a ferroelectric liquid-crystal spatial light modulator to test the feasible output size of a holographic switch. The demonstration proves that switching was achieved when the power of a laser diode used as the control light source was 6.3 mW. The average of the insertion loss was 31.6 dB.

An easy-to-handle optical device structure is proposed for optical parallel processing devices. This is an opto-electronic hybrid structure consisting of liquid crystal polarization controllers and polarizing beam splitters. Experimental memory and AND cells based on this structure are successfully demonstrated.