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Woven EndoBridge (WEB) was introduced for the endovascular therapy of wide-neck intracranial aneurysms. The safety and efficacy have been evaluated through several meta-analyses. However, these reviews did not cover the expanding indications in detail. Therefore, we aimed to show the changing trends for intracranial aneurysm treatment using the WEB device.A systematic review and meta-analysis was conducted with PubMed, Embase, and Cochrane databases. We searched for studies that reported baseline characteristics of aneurysms and the WEB devices, which had treated more than 20 aneurysms consecutively. The pooled proportions of aneurysm indications and used WEB device types were obtained. To evaluate the changing indications for the treated aneurysm size, including the neck diameter, a trend line and linear regression model was measured.A total of 27 cohorts were included encompassing 1831 aneurysms treated with the WEB. A total of 86% were used in the four major locations as on-label indications (middle cerebral artery bifurcation; 34%, anterior communicating artery; 26%, basilar tip; 18%, internal carotid artery terminus; 7%). Among off-label indications, the most common location was the posterior communicating artery (8%), followed by the anterior cerebral artery including the pericallosal artery (6%). The median aneurysm size and neck diameter was 7 mm and 4.6 mm, respectively. The WEB device has been used for the treatment of smaller aneurysms than the initial indication. Also, the proportion for ruptured aneurysm treatment was increased up to 15%.The mechanical and technical development of the WEB resulted in expanding the indications for the treatment of intracranial aneurysms. The off-label indications accounted for 14% in total and an increasing number of small aneurysms are treated with WEB devices. Moreover, the proportion for ruptured aneurysm treatment was currently increased up to 14% more than in the beginning.

Background The purpose of our study was to investigate the safety and effectiveness of a modified technique using a short guiding catheter for instillation of elastase in comparison with the previously described method of creating elastase-induced aneurysm in rabbits. Methods Following right common carotid artery (RCCA) access using an arterial sheath and inflating the Fogarty balloon in the subclavian artery, a short guiding catheter was used for the instillation of the elastase in the experimental group (n = 5) while it was performed with a microcatheter in the control group (n = 5). The procedure duration was recorded from the RCCA puncture to the sheath removal. The histological changes were characterized using H&E and Masson's trichrome (MT) staining. Results The procedure time was 23 ± 2 min in the experimental group and 29 ± 2 min in the control group. All the rabbits (100%) in the experimental group survived without neurologic deficits, but two rabbits (40%) survived in the control group. All aneurysms were created in the saccular shape (100%) with a neck size of 2.3 ± 0.29 mm, a width of 2.75 ± 0.36 mm, and height of 6.37 ± 0.46 mm, and a dome to neck ratio of 1.21 ± 0.23. The aneurysm walls were partly thickened due to the degradation of the media tunica and adventitia proliferation with loss of the internal elastic lamina. Conclusion By using a short guiding catheter, we could instill the elastase in a more effective and safe manner in the creation of the elastase-induced aneurysm model in rabbits.

In designing of the wind power facilities, the highest and lowest astronomical tides (HAT and LAT) are needed in terms of an international design tidal water levels. The AHHW and ALLW, however, have been used as the design tidal levels in Korea. The HAT and LAT in the Wido coastal sea should be estimated to satisfy the standard because the pilot wind power facilities will be located in the adjacent Wido coastal sea. In this study, the HAT and LAT are estimated using the 31-years hourly tidal elevation data of the Wido tidal gauging station and the nodal variation patterns of the major lunar components, such as , , and , are analysed to check the expected long-term lunar cycle, i.e., 18.61-year`s nodal variation patterns. The temporal amplitude variations of the , , and clearly show the 18.61-years periodic patterns in case of the no-nodal correction condition. In addition, the suggested HAT and LAT elevations, estimated as the upper and lower confidence limits of the yearly HAT and LAT elevations, show 40 cm greater than AHHW and 35 cm lower than ALLW, respectively.

Chun, J., Ahn, K., Yoon, J.-T., Suh, K.-D. and Kim, M., 2013. Projection of extreme typhoon wave : Case study at Busan, Korea Several studies predicted that the typhoons will be more intense in the future. Since the intensification makes the wave environments at the coastal zone more extreme, the analysis on the enhancement of typhoon waves is required for the future protection of the coastal zone. Most of the extreme wave analysis is based on the measured or hindcast wave data which does not reflect the future trend of variations. This study discuss the add-on effect of future typhoon intensification on the estimation of extreme waves. Especially, since the extreme waves at Busan port, Korea are generated by typhoons, the trends of the activity and intensity of typhoons on the southern coasts of Korean Peninsula between 1951 and 2010 were analyzed. At the analysis, it was found that there is a trend in the intensity of typhoons. By applying the wavelet analysis, the long-term trend of the intens...

In the present study, the dynamically coupled POM-WAM of Chun et al.(2009) was applied to the numerical simulation of undertow, one of the nearshore currents. To improve the accuracy of the numerical model results in surf zone, the transport equation of the surface roller was solved, and its effects were incorporated into the present numerical model. The numerical model has been applied to two hydraulic experiments of Okayasu and Katayama(1992) and Cox and Kobayashi(1997). The numerical results were compared with the hydraulic experimental results to give a good concurrence. It is concluded that the present numerical model can be applied to the shallow water region including surf zone.

This paper describes a technique, which enable one to overcome several difficulties encountered in a conventional deformed drop retraction method. The technique consists of forming deformed drops by the disintegration of a polymer thread and measuring the shape evolution of the drop. It is found that the technique enables one to overcome the difficulties encountered in the conventional deformed drop retraction method. By the optical microscope observation, it was confirmed that the disintegrated drop maintains the axisymmetrical ellipsoidal shape during the retraction process and was parallel to the observation plane. The interfacial tension obtained by the technique was found to be lower than the data from the breaking thread method. This variation was discussed in terms of the interfacial contact time.

The effect of polar comonomers introduced into polystyrene (PS) chains on the melt intercalation into organosilicate is investigated in terms of shear and annealing time. In the case, where the interaction between polymers and silicate layers is relatively weak, e.g. PS/organosilicate hybrids, it is difficult for the polymer chains to diffuse into interlayers of organosilicate and the hybrids are unstable under shear. For hybrids in which the interaction is enhanced by incorporating polar comonomers, e.g. acrylonitrile (AN) and methylvinyl oxzoline (OZ), their structures are stable even after a long mixing time. However, they do not show an exfoliated structure under the mixing conditions used in this study. The interaction between the comonomer and the silicate surface is investigated indirectly via both X-ray diffractional and FTIR spectral analyses. It is concluded that the structural stability of polymer/organosilicate hybrids is very dependent on the relative magnitude of the interactions between polymers, organic modifiers, and silicate layers.

Ternary blends of polysulfone (PSF)/polycarbonate (PC)/Impact modifiers (IM) were prepared to improve the mechanical properties of PSF/PC binary blends. Two different core–shell impact modifiers, methyl methacrylate–butadiene–ethylacrylate (MBE) and acrylonitrile–butadiene–styrene (ABS) terpolymers, were used. Morphology of the blends was very dependent on thc matrix type but independent of the IM type. For PSF matrix PC tends to encapsulate the IM. Whereas, for PC matrix, the IM tends to locate in PC matrix and thus two distinct phases of PSF and IM are observed. The encapsulation of PC onto the IM in PSF matrix was verified from the model blends of PSF/PC/SAN24 and PSF/PC/PMMA, where SAN24 and PMMA are corresponding to the shell of the IM, respectively. Impact strengths of the blends with the IM were slightly increased compared to PSF/PC binary blends, but not significantly. This may be the result of poor PSF/PC interfaces, which are valid from their immiscibility.

BaTiO3 fine powders were hydrothermally synthesized. The maximal size of cubic crystallite at room temperature was estimated by comparision of the size distributions on TEM and the x-ray powder diffraction intensities of the synthesized powders. The volume fraction of tetragonal powder in a batch was calculated from the x-ray diffraction pattern by the peak profile fitting method and the size distribution was counted on TEM micrographs of the powder. The critical size between cubic and tetragonal BaTiO3 powder at room temperature was calculated as 0.23μmlm

The miscibility of poly(vinylidene fluoride) (PVDF) and poly(styrene-co-methyl methacrylate) (SMMA) blends was examined as a function of copolymer composition. PVDF was miscible with SMMA copolymers having an styrene content less than 13 vol%. The segmental interaction parameters were determined by combining the equilibrium melting point depression of PVDF and the binary interaction model. According to the binary interaction model, the maximum styrene content in SMMA for the blend to be miscible was predicted as 18.5 vol% which agrees well with an experimental result.