Fine-pitch and thick-foil gas electron multipliers for cosmic x-ray polarimeters

We have produced various gas electron multiplier foils (GEMs) by using laser etching technique for cosmic X-ray polarimeters. The finest structure GEM we have fabricated has 30 μm-diameter holes on a 50 μm-pitch. The effective gain of the GEM reaches around 5000 at the voltage of 570 V between electrodes. The gain is slightly higher than that of the CERN standard GEM with 70 μm-diameter holes on a 140 μm-pitch. We have fabricated GEMs with thickness of 100 μm which has two times thicker than the standard GEM. The effective gain of the thick-foil GEM is 104 at the applied voltage of 350 V per 50 μm of thickness. The gain is about two orders higher than that of the standard GEM. The remarkable characteristic of the thick-foil GEM is that the effective gain at the beginning of micro-discharge is quite improved. For fabricating the thick-foil GEMs, we have employed new material, liquid crystal polymer (LCP) which has little moisture absorption rate, as an insulator layer instead of polyimide. One of the thick-foil GEM we have fabricated has 8 μm copper layer in the middle of the 100 μm-thick insulator layer. The metal layer in the middle of the foil works as a field-shaper in the multiplication channels, though it slightly decreases the effective gain

Expansion Velocity of Ejecta in Tycho's Supernova Remnant Measured by Doppler Broadened X-ray Line Emission

We show that the expansion of ejecta in Tycho's supernova remnant (SNR) is consistent with a spherically symmetric shell, based on Suzaku measurements of the Doppler broadened X-ray emission lines. All the strong K_alpha line emission show broader widths at the center than at the rim, while the centroid energies are constant across the remnant (except for Ca). This is the pattern expected for Doppler broadening due to expansion of the SNR ejecta in a spherical shell. To determine the expansion velocities of the ejecta, we applied a model for each emission line feature having two Gaussian components separately representing red- and blue-shifted gas, and inferred the Doppler velocity difference between these two components directly from the fitted centroid energy difference. Taking into account the effect of projecting a three-dimensional shell to the plane of the detector, we derived average spherical expansion velocities independently for the K_alpha emission of Si, S, Ar, and Fe, and K_beta of Si. We found that the expansion velocities of Si, S, and Ar ejecta of 4700+/-100 km/s are distinctly higher than that obtained from Fe K_alpha emission, 4000+/-300 km/s, which is consistent with segregation of the Fe in the inner ejecta. Combining the observed ejecta velocities with the ejecta proper-motion measurements by Chandra, we derived a distance to the Tycho's SNR of 4+/-1 kpc.Comment: Accepted to Apj, 25 pages, 7 figures, 5 table

Development of Thick-foil and Fine-pitch GEMs with a Laser Etching Technique

We have produced thick-foil and fine-pitch gas electron multipliers (GEMs) using a laser etching technique. To improve production yield we have employed a new material, Liquid Crystal Polymer, instead of polyimide as an insulator layer. The effective gain of the thick-foil GEM with a hole pitch of 140 um, a hole diameter of 70 um, and a thickness of 100 um reached a value of 10^4 at an applied voltage of 720 V. The measured effective gain of the thick-foil and fine-pitch GEM (80 um pitch, 40 um diameter, and 100 um thick) was similar to that of the thick-foil GEM. The gain stability was measured for the thick-foil and fine-pitch GEM, showing no significant increase or decrease as a function of elapsed time from applying the high voltage. The gain stability over 3 h of operation was about 0.5%. Gain mapping across the GEM showed a good uniformity with a standard deviation of about 4%. The distribution of hole diameters across the GEM was homogeneous with a standard deviation of about 3%. There was no clear correlation between the gain and hole diameter maps.Comment: 21 pages, 9 figure

A New Lead Chemical for Strigolactone Biosynthesis Inhibitors

Several triazole-containing chemicals have previously been shown to act as efficient inhibitors of cytochrome P450 monooxygenases. To discover a strigolactone biosynthesis inhibitor, we screened a chemical library of triazole derivatives to find chemicals that induce tiller bud outgrowth of rice seedlings. We discovered a triazole-type chemical, TIS13 [2,2-dimethyl-7-phenoxy-4-(1H-1,2,4-triazol-1-yl)heptan-3-ol], which induced outgrowth of second tiller buds of wild-type seedlings, as observed for non-treated strigolactone-deficient d10 mutant seedlings. TIS13 treatment reduced strigolactone levels in both roots and root exudates in a concentration-dependent manner. Co-application of GR24, a synthetic strigolactone, with TIS13 canceled the TIS13-induced tiller bud outgrowth. Taken together, these results indicate that TIS13 inhibits strigolactone biosynthesis in rice seedlings. We propose that TIS13 is a new lead compound for the development of specific strigolactone biosynthesis inhibitors

Epidemiologic profile of type-specific human papillomavirus infection after initiation of HPV vaccination

Funding Information: This work was supported by the Health and Labor Sciences Research Grant [26272001] and the Japanese Agency for Medical Research and Development [JP15ck0106103]. Acknowledgments: We would like to thank Yuka Watanabe, Sachiko Ono, Anna Ishida, Yoko Motoki and the administrator of Niigata city for their support in conducting the surveyPeer reviewedPublisher PD

Japan's Ongoing Crisis on HPV Vaccination.

Funding: This work was supported by the Health and Labor Sciences Research Grant [26272001] and the Japanese Agency for Medical Research and Development [JP15ck0106103]. Acknowledgments: We would like to thank Yuka Watanabe, Sachiko Ono, Anna Ishida, Yoko Motoki, Tomomi Egawa-Takata, Akiko Morimoto, Yusuke Tanaka and the administrator of Niigata city for their support in conducting the surveyPeer reviewedPublisher PD

Internet Survey of Awareness and Behavior Related to HPV Vaccination in Japan

Funding Information: Funding: This work was supported by the Health and Labor Sciences Research Grant No. 26272001 and the Japanese Agency for Medical Research and Development (JP15ck0106103).Peer reviewedPublisher PD

Long-term effectiveness of HPV vaccination against HPV infection in young Japanese women : Real-world data.

ACKNOWLEDGEMENTS We would like to thank Ms. Yuka Watanabe, Ms. Sachiko Ono, Ms. Anna Ishida, and the administrator of Niigata city for their support in conducting the surveyPeer reviewedPublisher PD