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Your search keyword '"Sawada, Makoto"' showing total 41 results
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41 results on '"Sawada, Makoto"'

1. Probing Shocked Ejecta in SN 1987A with XRISM-Resolve: the effects of the gate valve closed

Author

Sapienza, Vincenzo, Miceli, Marco, Bamba, Aya, Orlando, Salvatore, Lee, Shiu-Hang, Nagataki, Shigehiro, Ono, Masaomi, Katsuda, Satoru, Mori, Koji, Sawada, Makoto, Terada, Yukikatsu, Giuffrida, Roberta, and Bocchino, Fabrizio

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Supernova (SN) 1987A is widely regarded as an excellent candidate for leveraging the capabilities of the freshly launched XRISM satellite. Recent researches indicate that the X-ray emission from SN 1987A will increasingly originate from its ejecta in the years to come. In a previous study, we thoroughly examined the proficiency of XRISM-Resolve in identifying signatures of shocked ejecta in SN 1987A, synthesizing the XRISM-Resolve spectrum based on a state-of-the-art magneto-hydrodynamic simulation. However, following the satellite's launch, a technical issue arose with the XRISM instrument's gate valve, which failed to open, thereby affecting observations with the Resolve spectrometer. Here, we update our analysis, reevaluating our diagnostic approach under the assumption that the gate valve remains closed. We find that, even with the reduced instrumental capabilities, it will be possible to pinpoint the ejecta contribution through the study of the line profiles in the XRISM-Resolve spectrum of SN 1987A., Comment: 4 pages, 1 figure. Updates of the results described in Sapienza et al. 2024 (http://doi.org/10.3847/2041-8213/ad16e3). Submitted for publication in Research Notes of the AAS

Published
2024

2. Is the low-energy tail of shock-accelerated protons responsible for over-ionized plasma in supernova remnants?

Author

Sawada, Makoto, Gu, Liyi, and Yamazaki, Ryo

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Over-ionized, recombining plasma is an emerging class of X-ray bright supernova remnants (SNRs). This unique thermal state where the ionization temperature ($T_{\rm z}$) is significantly higher than the electron temperature ($T_{\rm e}$) is not expected from the standard evolution model assuming a point explosion in a uniform interstellar medium, requiring a new scenario for the dynamical and thermal evolution. A recently proposed idea attributes the over-ionization state to additional ionization contribution from the low-energy tail of shock-accelerated protons. However, this new scenario has been left untested, especially from the atomic physics point of view. We report calculation results of the proton impact ionization rates of heavy-element ions in ejecta of SNRs. We conservatively estimate the requirement for accelerated protons, and find that their relative number density to thermal electrons needs to be higher than $5~(T_{\rm e}/{\rm 1~keV})\%$ in order to explain the observed over-ionization degree at $T_{\rm z}/T_{\rm e} \ge 2$ for K-shell emission. We conclude that the proton ionization scenario is not feasible because such a high abundance of accelerated protons is prohibited by the injection fraction from thermal to non-thermal energies, which is expected to be $\sim 1\%$ at largest., Comment: 16 pages, 10 figures, submitted to PASJ

Published
2024

3. Missing Titanium in the Asymmetric Supernova Remnant W49B

Author

Sato, Toshiki, Sawada, Makoto, Maeda, Keiichi, Hughes, John P., and Williams, Brian J.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

The progenitor of the W49B supernova remnant is still under debate. One of the candidates is a jet-driven core-collapse supernova. In such a highly asymmetric explosion, a strong $\alpha$-rich freezeout is expected in local high entropy regions, which should enrich elements synthesized by the capture of $\alpha$-particles such as $^{44}$Ti and $^{48}$Cr (decaying to $^{44}$Ca and $^{48}$Ti, respectively). In the present work, in order to infer the progenitor of the W49B remnant, we constrain the amount of stable Ti ($^{48}$Ti) synthesized, using the {\it Suzaku} observation. We found no firm evidence for the Ti line and set the upper limit of $M_{\rm Ti}/M_{\rm Fe} < 8.2 \times$ 10$^{-4}$ (99\% limit using Xspec) and $M_{\rm Ti}/M_{\rm Fe} < 1.9 \times$ 10$^{-3}$ (99\% limit using SPEX), and thus excluded almost all hypernova/jet-driven supernova models. Our results, as complemented by some previous studies, suggest that a Type Ia supernova from a near-$M_{\rm Ch}$ (Chandrasekhar mass) white dwarf is the most favorable candidate for the origin of W49B. Future observations with X-ray calorimeter missions, such as XRISM, will give us a stronger constraint on the progenitor., Comment: Submitted to ApJ, 7 pages, 3 figures, 1 table

Published
2024

4. High count rate effects in event processing for XRISM/Resolve x-ray microcalorimeter

Author

Mizumoto, Misaki, Tsujimoto, Masahiro, Cumbee, Renata S., Eckart, Megan E., Ishisaki, Yoshitaka, Kilbourne, Caroline A., Hodges-Kluck, Edmund, Leutenegger, Maurice A., Porter, Frederick S., Sawada, Makoto, Takei, Yoh, Uchida, Yuusuke, Yamada, Shin'ya, and team, the XRISM Resolve

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics
Abstract

The spectroscopic performance of x-ray instruments can be affected at high count rates. The effects and mitigation in the optical chain, such as x-ray attenuation filters or de-focusing mirrors, are widely discussed, but those in the signal chain are not. Using the Resolve x-ray microcalorimeter onboard the XRISM satellite, we discuss the effects observed during high count rate measurements and how these can be modeled. We focus on three instrumental effects that impact performance at high count rate: CPU limit, pile up, and electrical cross talk. High count rate data were obtained during ground testing using the flight model instrument and a calibration x-ray source. A simulated observation of GX 13+1 is presented to illustrate how to estimate these effects based on these models for observation planning. The impact of these effects on high count rate observations is discussed., Comment: 16 pages, 20 figures, Proc. SPIE

Published
2023
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5. Probing Shocked Ejecta in SN 1987A: A novel diagnostic approach using XRISM-Resolve

Author

Sapienza, Vincenzo, Miceli, Marco, Bamba, Aya, Orlando, Salvatore, Lee, Shiu-Hang, Nagataki, Shigehiro, Ono, Masaomi, Katsuda, Satoru, Mori, Koji, Sawada, Makoto, Terada, Yukikatsu, Giuffrida, Roberta, and Bocchino, Fabrizio

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Supernova (SN) 1987A is one of the best candidates to exploit the capabilities of the freshly launched XRISM satellite. This celestial object offers the unique opportunity to study the evolution of a SN into a young supernova remnant. To date, the X-ray emission has been dominated by the shocked circumstellar medium (CSM), with no shocked ejecta firmly detected. However, recent studies provide compelling evidence that in the forthcoming years the X-ray emission from SN 1987A will increasingly stem from the ejecta. Our aim is to assess the proficiency of XRISM-Resolve high resolution spectrometer in pinpointing signatures of the shocked ejecta in SN 1987A. Taking advantage of a self consistent state-of-art magneto-hydrodynamic simulation that describes the evolution from SN 1987A to its remnant, we synthesized the XRISM-Resolve spectrum of SN 1987A, as it would be collected in the allocated observation during the performance verification phase, which is foreseen for 2024. Our predictions clearly show the leading role of shocked ejecta in shaping the profile of the emission lines. The Doppler broadening associated with the bulk motion along the line of sight of the rapidly expanding ejecta is shown to increase the line widths well above the values observed so far. The quantitative comparison between our synthetic spectra and the XRISM spectra will enable us to establish a strong connection between the broadened line emission and the freshly shocked ejecta. This, in turn, will allow us to retrieve the ejecta dynamics and chemical composition from the X-ray emission., Comment: 9 pages, 4 figures, 1 table, Accepted for publication in The Astrophysical Journal Letters

Published
2023

6. Photosensitizer-singlet oxygen sensor conjugated silica nanoparticles for photodynamic therapy and bioimaging.

Author

Sobhanan, Jeladhara, Ono, Kenji, Okamoto, Takuya, Sawada, Makoto, Weiss, Paul, and Biju, Vasudevanpillai

Abstract

Intracellular singlet oxygen (1O2) generation and detection help optimize the outcome of photodynamic therapy (PDT). Theranostics programmed for on-demand phototriggered 1O2 release and bioimaging have great potential to transform PDT. We demonstrate an ultrasensitive fluorescence turn-on sensor-sensitizer-RGD peptide-silica nanoarchitecture and its 1O2 generation-releasing-storing-sensing properties at the single-particle level or in living cells. The sensor and sensitizer in the nanoarchitecture are an aminomethyl anthracene (AMA)-coumarin dyad and a porphyrin or CdSe/ZnS quantum dots (QDs), respectively. The AMA in the dyad quantitatively quenches the fluorescence of coumarin by intramolecular electron transfer, the porphyrin or QD moiety generates 1O2, and the RGD peptide facilitates intracellular delivery. The small size, below 200 nm, as verified by scanning electron microscopy and differential light scattering measurements, of the architecture within the 1O2 diffusion length enables fast and efficient intracellular fluorescence switching by the tandem ultraviolet (UV)-visible or visible-near-infrared (NIR) photo-triggering. While the red emission and 1O2 generation by the porphyrin are continually turned on, the blue emission of coumarin is uncaged into 230-fold intensity enhancement by on-demand photo-triggering. The 1O2 production and release by the nanoarchitecture enable spectro-temporally controlled cell imaging and apoptotic cell death; the latter is verified from cytotoxic data under dark and phototriggering conditions. Furthermore, the bioimaging potential of the TCPP-based nanoarchitecture is examined in vivo in B6 mice.

Published
2024

7. X-ray spectra of the Fe-L complex III: systematic uncertainties in the atomic data

Author

Gu, Liyi, Shah, Chintan, Mao, Junjie, Raassen, A. J. J., de Plaa, Jelle, Pinto, Ciro, Akamatsu, Hiroki, Werner, Norbert, Simionescu, Aurora, Mernier, Francois, Sawada, Makoto, Mohanty, Pranav, Amaro, Pedro, Gu, Ming Feng, Porter, F. Scott, Lopez-Urrutia, Jose R. Crespo, and Kaastra, Jelle S.

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Physics - Atomic Physics
Abstract

There has been a growing request from the X-ray astronomy community for a quantitative estimate of systematic uncertainties originating from the atomic data used in plasma codes. Though there have been several studies looking into atomic data uncertainties using theoretical calculations, in general, there is no commonly accepted solution for this task. We present a new approach for estimating uncertainties in the line emissivities for the current models of collisional plasma, mainly based upon dedicated analysis of observed high resolution spectra of stellar coronae and galaxy clusters. We find that the systematic uncertainties of the observed lines consistently show anti-correlation with the model line fluxes, after properly accounting for the additional uncertainties from the ion concentration calculation. The strong lines in the spectra are in general better reproduced, indicating that the atomic data and modeling of the main transitions are more accurate than those for the minor ones. This underlying anti-correlation is found to be roughly independent on source properties, line positions, ion species, and the line formation processes. We further apply our method to the simulated XRISM and Athena observations of collisional plasma sources and discuss the impact of uncertainties on the interpretation of these spectra. The typical uncertainties are 1-2% on temperature and 3-20% on abundances of O, Ne, Fe, Mg, and Ni., Comment: 18 pages, 18 figures, accepted for publication in Astronomy & Astrophysics

Published
2022
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10. Dark matter search in the Perseus cluster with simultaneous analysis of Hitomi and Suzaku data.

Author

Fukuichi, Makoto, Kitamoto, Shunji, Sawada, Makoto, and Tamura, Takayuki

Subjects
DARK matter, CLUSTER analysis (Statistics), GALAXY clusters, X-ray spectrometers, STERILE neutrinos, X-ray astronomy, WEAKLY interacting massive particles, MASS transfer
Abstract

The reported detection of a 3.5 keV emission line in the Perseus cluster, possibly originating from dark matter decay, is still under scrutiny. Despite extensive observations, the detection has not yet been confirmed, and its origin remains a topic of active debate. Most of the previous searches relied on spectroscopy with X-ray charge-coupled devices, such as the X-ray Imaging Spectrometer on Suzaku. Although this provided a large amount of observational data, it only offered moderate spectral resolution. The X-ray astronomy satellite Hitomi offers new results using its high-resolution X-ray spectrometer (Soft X-ray Spectrometer). However, the data gathered were somewhat limited in terms of statistics. In this work, we present the results of a new spectral analysis of the Perseus cluster that combines the spectra from the XIS and SXS, along with the Soft X-ray Imager on Hitomi, thereby complementing each other's capability. Our search was conducted for a line emission or absorption in the energy range of 2.6–5.9 keV assuming the Navarro–Frenk–White mass distribution with a concentration parameter of 5.0 and virial radius, r 200, of 1.79 Mpc. We also considered the instrumental systematic uncertainty caused by the effective area calibration, which we empirically evaluated using the Crab Nebula spectra. On combining these results, we found no significant line features above the baryonic thermal emission from the intra-cluster medium. The upper limit at 3.5 keV, at a 3σ confidence level, is tightly constrained to 4.2 × 10−5 photons cm−2 s−1 for the |$15^{\prime }$| circular sky region, which encloses a dark matter mass of |$1.67\times 10^{14}\, M_{\odot }$|⁠ , assuming a line velocity dispersion of 180 km s−1. This constraint is three times tighter than the previous one, which only used the SXS. On the basis of these findings, we provide the upper limit of the dark matter decay rate and the mixing angle for the sterile neutrino origin. [ABSTRACT FROM AUTHOR]

Published
2024
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12. In-orbit operation of Resolve Filter Wheel and MXS

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Shipman, Russell F., Kitamoto, Shunji, Wolfs, Rob, Costantini, Elisa, Eckart, Megan E., Ferrigno, Carlo, Genolet, Ludovic, Gorter, Nathalie, Grim, Martin, den Herder, Jan Willem, Kilbourne, Caroline A., Leutenegger, Maurice A., van der Meer, Erik, Mizumoto, Misaki, Porter, F. Scott, Paltani, Stéphane, Sawada, Makoto, Strotmann, Simon, Tsujimoto, Masahiro, and de Vries, Cor P.

Published
2024
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13. Detail design of the XRISM timing system and its verification in the nominal operation mode

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Terada, Yukikatsu, Shidatsu, Megumi, Sawada, Makoto, Kominato, Takashi, Kato, So, Sato, Ryohei, Sakama, Minami, Shioiri, Takumi, Niida, Yuki, Natsukari, Chikara, Tashiro, Makoto S., Toda, Kenichi, Maejima, Hironori, Hayashi, Katsuhiro, Yoshida, Tessei, Ogawa, Shoji, Kanemaru, Yoshiaki, Hoshino, Akio, Fukushima, Kotaro, Takahashi, Hiromitsu, Nobukawa, Masayoshi, Mizuno, Tsunefumi, Nakazawa, Kazuhiro, Uno, Shin'ichiro, Ebisawa, Ken, Eguchi, Satoshi, Katsuda, Satoru, Kubota, Aya, Ota, Naomi, Tanimoto, Atsushi, Terashima, Yuichi, Tsuboi, Yohko, Uchida, Yusuke, Uchiyama, Hideki, Yamauchi, Shigeo, Yoneyama, Tomokage, Yamada, Satoshi, Uchida, Nagomi, Watanabe, Shin, Iizuka, Ryo, Sato, Rie, Baluta, Chris, Holland, Matt, Loewenstein, Michael, Miller, Eric D., Yaqoob, Tahir, Hill, Robert S., Doyle, Trisha F., Perez-Solis, Efrain, Waddy, Morgan D., Mekosh, Mark, Fox, Joseph B., Takagi, Toshihiro, Motogami, Yugo, Pottschmidt, Katja, Enoto, Teruaki, and Tanaka, Takaaki

Published
2024
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14. Energy gain scale calibration of the XRISM Resolve microcalorimeter spectrometer: ground calibration results and on-orbit comparison

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Eckart, Megan E., Brown, Gregory V., Chiao, Meng P., Cumbee, Renata S., Fujimoto, Ryuichi, Hell, Natalie, Hoshino, Akio, Ishisaki, Yoshitaka, Kelley, Richard L., Kenyon, Steven J., Kilbourne, Caroline A., Kitamoto, Shunji, Leutenegger, Maurice A., Lockard, Tom, Loewenstein, Michael, Magee, Edward W., Mizumoto, Misaki, Porter, F. Scott, Sato, Kosuke, Sawada, Makoto, Shah, Chintan, Shipman, Russell F., Sneiderman, Gary A., Takei, Yoh, Tsujimoto, Masahiro, de Vries, Cor P., Watanabe, Tomomi, Witthoeft, Michael C., Wolfs, Rob, Yamada, Shinya, and Yaqoob, Tahir

Published
2024
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15. In-orbit performance of the XMA for XRISM/Resolve

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Hayashi, Takayuki, Boissay-Malaquin, Rozenn, Tamura, Keisuke, Okajima, Takashi, Eckart, Megan E., Leutenegger, Maurice A., Yaqoob, Tahir, Loewenstein, Mike, Kelley, Richard L., Porter, F. Scott, Kilbourne, Caroline A., Chiao, Meng P., Sneiderman, Gary A., Cumbee, Renata S., Ishisaki, Yoshitaka, Fujimoto, Ryuichi, Tsujimoto, Masahiro, Sawada, Makoto, Sato, Toshiki, Maeda, Yoshitomo, Ishida, Manabu, Corrales, Lia, Miller, Eric, Tumer, Aysegul, Takahashi, Hiromitsu, Brenneman, Laura, Kanemaru, Yoshiaki, Mizumoto, Misaki, Markevitch, Maxim, and Guainazzi, Matteo

Published
2024
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16. In-flight performance of the XRISM/Resolve detector system

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Porter, Frederick S., Kilbourne, Caroline A., Chiao, Meng, Cumbee, Renata, Eckart, Megan E., Fujimoto, Ryuichi, Ishisaki, Yoshitaka, Kanemaru, Yoshiaki, Kelley, Richard L., Leutenegger, Maurice, Maeda, Yoshitomo, Mizumoto, Misaki, Sato, Kosuke, Sawada, Makoto, Sneiderman, Gary, Takei, Yoh, Tsujimoto, Masahiro, Uchida, Yuusuke, Watanabe, Tomomi, and Yamada, Shinya

Published
2024
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17. Development and operation status of X-Ray Imaging and Spectroscopy Mission (XRISM)

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Tashiro, Makoto, Watanabe, Shin, Maejima, Hironori, Toda, Kenichi, Matsushita, Kyoko, Yamaguchi, Hiroya, Kelley, Richard, Reichenthal, Lillian, Hartz, Leslie, Petre, Robert, Williams, Brian, Guainazzi, Matteo, Santovincenzo, Andrea, Costantini, Elisa, Takei, Yoh, Ishisaki, Yoshitaka, Fujimoto, Ryuichi, Henegar-Leon, Joy, Sneiderman, Gary, Tomida, Hiroshi, Mori, Koji, Nakajima, Hiroshi, Terada, Yukikatsu, Holland, Matt, Loewenstein, Micheal, Kallman, Timothy, Kaastra, Jelle, Miller, Eric, Sawada, Makoto, Done, Chris, Enoto, Teruaki, Bamba, Aya, Plucinsky, Paul, Ueda, Yoshihiro, Kara, Erin, Zhuravleva, Irina, Fujita, Yutaka, Querro, Jose Antonio, Arai, Yoshitaka, Audard, Marc, Awaki, Hisamitsu, Baluta, Chris, Bando, Nobutaka, Behar, Ehud, Bialas, Thomas, Boissay-Malaquin, Rozenn, Brenneman, Laura, Brown, Gregory V., Chiao, Meng, Corrales, Lia, Cumbee, Renata, de Vries, Cor, den Herder, Jan-Willem, Diaz-Trigo, Maria, DiPirro, Michael, Dotani, Tadayasu, Ebrero Carrero, Jacobo, Ebisawa, Ken, Eckart, Megan, Eckart, Dominique, Eguchi, Satoshi, Ezoe, Yuichiro, Ferrigno, Carlo, Foster, Adam, Fukazawa, Yasushi, Fukushima, Kotaro, Furuzawa, Akihiro, Gallo, Luigi, Gorter, Nathalie, Grim, Martin, Gu, Liyi, Hagino, Koichi, Hamaguchi, Kenji, Hatsukade, Isamu, Hayashi, Katsuhiro, Hayashi, Takayuki, Hell, Natalie, Hodges-Kluck, Edmund, Horiuchi, Takafumi, Hornschemeier, Ann, Hoshino, Akio, Ichinohe, Yuto, Ikuta, Chisato, Iizuka, Ryo, Ishi, Daiki, Ishida, Manabu, Ishihama, Naoki, Ishikawa, Kumi, Ishimura, Kosei, Jaffe, Tess, Katsuda, Satoru, Kanemaru, Yoshiaki, Kenyon, Steven, Kilbourne, Caroline, Kimball, Mark, Kitamoto, Shunji, Kobayashi, Shogo, Kobayashi, Akihide, Kohmura, Takayoshi, Kubota, Aya, Leutenegger, Maurice, Li, Muzi, Maeda, Yoshitomo, Markevitch, Maxim, Matsumoto, Hironori, Matsuzaki, Keiichi, McCammon, Dan, McLaughlin, Brian, McNamara, Brian, Miko, Joseph, Miller, Jon, Minesugi, Kenji, Mitani, Shinji, Mitsuishi, Ikuyuki, Mizumoto, Misaki, Mizuno, Tsunefumi, Mukai, Koji, Murakami, Hiroshi, Mushotzky, Richard, Nakazawa, Kazuhiro, Natsukari, Chikara, Ness, Jan-Uwe, Nigo, Kenichiro, Nishiyama, Mari, Nobukawa, Kumiko, Nobukawa, Masayoshi, Noda, Hirofumi, Odaka, Hirokazu, Ogawa, Mina, Ogawa, Shoji, Okajima, Takashi, Okamoto, Atsushi, Ota, Naomi, Ozaki, Masanobu, Paltani, Stephane, Porter, F. Scott, Pottschmidt, Katja, Sasaki, Takahiro, Sato, Kosuke, Sato, Rie, Sato, Toshiki, Sato, Yoichi, Seta, Hiromi, Shida, Maki, Shidatsu, Megumi, Shigeto, Shuhei, Shipman, Russel, Shinozaki, Keisuke, Shirron, Peter, Simionescu, Aurora, Smith, Randall, Soong, Yang, Suzuki, Hiromasa, Szymkowiak, Andy, Takahashi, Hiromitsu, Takeo, Mai, Tamagawa, Toru, Tamura, Keisuke, Tanaka, Takaaki, Tanimoto, Atsushi, Terashima, Yuichi, Tsuboi, Yohko, Tsujimoto, Masahiro, Tsunemi, Hiroshi, Tsuru, Takeshi, Uchida, Hiroyuki, Uchida, Nagomi, Uchida, Yuusuke, Uchiyama, Hideki, Uno, Shinichiro, Van der Meer, Erik, Vink, Jacco, Wittheof, Michael, Wolfs, Rob, Yamada, Satoshi, Yamada, Shinya, Yamaoka, Kazutaka, Yamasaki, Noriko, Yamauchi, Makoto, Yamauchi, Shigeo, Yanagase, Keiichi, Yaqoob, Tahir, Yasuda, Susumu, Yoneyama, Tomokage, and Yoshida, Tessei

Published
2024
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20. Pulse parameters optimization of the modulated x-ray sources for the resolve microcalorimeter spectrometer on XRISM

Author

Sawada, Makoto, primary, Cumbee, Renata S., additional, de Vries, Cor P., additional, Eckart, Megan E., additional, Fujimoto, Ryuichi, additional, Ishisaki, Yoshitaka, additional, Kilbourne, Caroline A., additional, Kitamoto, Shunji, additional, Leutenegger, Maurice A., additional, Porter, Frederick S., additional, Takei, Yoh, additional, and Tsujimoto, Masahiro, additional

Published
2022
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21. Status of resolve instrument onboard x-ray imaging and spectroscopy mission (XRISM)

Author

Ishisaki, Yoshitaka, primary, Kelley, Richard L., additional, Awaki, Hisamitsu, additional, Balleza, Jesus C., additional, Barnstable, Kim R., additional, Bialas, Thomas G., additional, Boissay-Malaquin, Rozenn, additional, Brown, Gregory V., additional, Canavan, Edgar R., additional, Cumbee, Renata S., additional, Carnahan, Timothy M., additional, Chiao, Meng P., additional, Comber, Brian J., additional, Costantini, Elisa, additional, den Herder, Jan-Willem A., additional, Dercksen, Johannes, additional, de Vries, Cor P., additional, DiPirro, Michael J., additional, Eckart, Megan E., additional, Ezoe, Yuichiro, additional, Ferrigno, Carlo, additional, Fujimoto, Ryuichi, additional, Gorter, Nathalie, additional, Graham, Steven M., additional, Grim, Martin, additional, Hartz, Leslie S., additional, Hayakawa, Ryota, additional, Hayashi, Takayuki, additional, Hell, Natalie, additional, Hoshino, Akio, additional, Ichinohe, Yuto, additional, Ishida, Manabu, additional, Ishikawa, Kumi, additional, James, Bryan L., additional, Kenyon, Steven J., additional, Kilbourne, Caroline A., additional, Kimball, Mark O., additional, Kitamoto, Shunji, additional, Leutenegger, Maurice A., additional, Maeda, Yoshitomo, additional, McCammon, Dan, additional, Miko, Joseph J., additional, Mizumoto, Misaki, additional, Okajima, Takashi, additional, Okamoto, Atsushi, additional, Paltani, Stephane, additional, Porter, Frederick S., additional, Sato, Kosuke, additional, Sato, Toshiki, additional, Sawada, Makoto, additional, Shinozaki, Keisuke, additional, Shipman, Russell, additional, Shirron, Peter J., additional, Sneiderman, Gary A., additional, Soong, Yang, additional, Szymkiewicz, Richard, additional, Szymkowiak, Andrew E., additional, Takei, Yoh, additional, Tamura, Keisuke, additional, Tsujimoto, Masahiro, additional, Uchida, Yuusuke, additional, Wasserzug, Stephen, additional, Witthoeft, Michael C., additional, Wolfs, Rob, additional, Yamada, Shinya, additional, and Yasuda, Susumu, additional

Published
2022
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22. Relative timing calibration of the Resolve x-ray microcalorimeter onboard XRISM using the modulated x-ray source

Author

Omama, Tomoki, primary, Tsujimoto, Masahiro, additional, Sawada, Makoto, additional, Kilbourne, Caroline A., additional, Vries, Cor ., additional, Eckart, Megan E., additional, Ishisaki, Yoshitaka, additional, Kitamoto, Shunji, additional, Leutenegger, Maurice A., additional, Porter, Frederick S., additional, and Wolfs, Rob, additional

Published
2022
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23. High count rate effects in event processing for XRISM/Resolve x-ray microcalorimeter

Author

Mizumoto, Misaki, primary, Tsujimoto, Masahiro, additional, Cumbee, Renata, additional, Eckart, Megan E., additional, Ishisaki, Yoshitaka, additional, Kilbourne, Caroline A., additional, Hodges-Kluck, Edmund, additional, Leutenegger, Maurice A., additional, Porter, Frederick S., additional, Sawada, Makoto, additional, Takei, Yoh, additional, Uchida, Yuusuke, additional, and Yamada, Shinya, additional

Published
2022
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24. Results of accelerometer monitor in the ground testing of Resolve x-ray microcalorimeter instrument onboard XRISM

Author

Imamura, Ryuta, primary, Tsujimoto, Masahiro, additional, Awaki, Hisamitsu, additional, Chiao, Meng P., additional, Fujimoto, Ryuichi, additional, Ishisaki, Yoshitaka, additional, Kelley, Richard L., additional, Kilbourne, Caroline A., additional, Porter, Frederick S., additional, Sawada, Makoto, additional, Sneiderman, Gary A., additional, Takei, Yoh, additional, and Yamada, Shinya, additional

Published
2022
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25. Secretion of signal peptides via extracellular vesicles

Author

Ono, Kenji, Niwa, Mikio, Suzuki, Hiromi, Kobayashi, Nahoko Bailey, Yoshida, Tetsuhiko, Sawada, Makoto, Ono, Kenji, Niwa, Mikio, Suzuki, Hiromi, Kobayashi, Nahoko Bailey, Yoshida, Tetsuhiko, and Sawada, Makoto

Abstract

Signal peptides (SPs) consist of short peptide sequences present at the N-terminal of newly synthesizing proteins and act as a zip code for the translocation of the proteins to the endoplasmic reticulum (ER). It was thought that the SPs are intracellularly degraded after translocation to the ER; however, recent studies showed cleaved SPs have diverse roles for controlling cell functions in auto- and/or intercellular manners. In addition, it still remains obscure how SP fragments translocate away from the site where they are produced. Extracellular vesicles (EV) are important for intercellular communication and can transport functional molecules to specific cells. In this study, we show that SPs are involved in EV from T-REx AspALP cells that were transfected with a human APP SP-inducible expression vector. There was no difference in the average particle size or particle concentration of EV collected from T-REx AspALP cells and T-REx Mock cells. When the SP content in the EV was examined by mass spectrometry, the C-terminal fragment of APP SP was identified in the exosomes (SEV) of T-REx AspALP cells. In our preparation of SEV fractions, no ER-specific proteins were detected; therefore, SPs may be included in SEV but not in the debris of degraded ER. This is the first indication that SPs are secreted from cells via EV.

Published
2022

27. Calmodulin as a Key Regulator of Exosomal Signal Peptides.

Author

Ono, Kenji, Niwa, Mikio, Suzuki, Hiromi, Kobayashi, Nahoko Bailey, Yoshida, Tetsuhiko, and Sawada, Makoto

Subjects
CALMODULIN, SIGNAL peptides, HEAT shock proteins, AMYLOID beta-protein precursor, EXOSOMES, EXTRACELLULAR fluid
Abstract

Signal peptides (SPs) and their fragments play important roles as biomarkers and substances with physiological functions in extracellular fluid. We previously reported that SP fragments were released into extracellular fluid via exosomes and bound to calmodulin (CaM), an exosomal component, in a cell-free system. However, it currently remains unclear whether CaM intracellularly interacts with SP fragments or is involved in the trafficking of these fragments to exosomes. Therefore, the present study examined the binding of CaM to SP fragments in T-REx AspALP cells, transformed HEK293 cells expressing amyloid precursor protein (APP) SP flanking a reporter protein, and their exosomes. APP SP fragments were detected in exosomes from T-REx AspALP cells in the absence of W13, a CaM inhibitor, but were present in lower amounts in exosomes from W13-treated cells. Cargo proteins, such as Alix, CD63, and CD81, were increased in W13-treated T-REx AspALP cells but were decreased in their exosomes. Furthermore, CaM interacted with heat shock protein 70 and CD81 in T-REx AspALP cells and this increased in the presence of W13. APP SP fragments were detected in intracellular CaM complexes in the absence of W13, but not in its presence. These results indicate that CaM functions as a key regulator of the transport of SP fragments into exosomes and plays novel roles in the sorting of contents during exosomal biogenesis. [ABSTRACT FROM AUTHOR]

Published
2023
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29. Status of resolve instrument onboard X-Ray Imaging and Spectroscopy Mission (XRISM)

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Ishisaki, Yoshitaka, Kelley, Richard L., Awaki, Hisamitsu, Balleza, Jesus C., Barnstable, Kim R., Bialas, Thomas G., Boissay-Malaquin, Rozenn, Brown, Gregory V., Canavan, Edgar R., Cumbee, Renata S., Carnahan, Timothy M., Chiao, Meng P., Comber, Brian J., Costantini, Elisa, den Herder, Jan-Willem, Dercksen, Johannes, de Vries, Cor P., DiPirro, Michael J., Eckart, Megan E., Ezoe, Yuichiro, Ferrigno, Carlo, Fujimoto, Ryuichi, Gorter, Nathalie, Graham, Steven M., Grim, Martin, Hartz, Leslie S., Hayakawa, Ryota, Hayashi, Takayuki, Hell, Natalie, Hoshino, Akio, Ichinohe, Yuto, Ishida, Manabu, Ishikawa, Kumi, James, Bryan L., Kenyon, Steven J., Kilbourne, Caroline A., Kimball, Mark O., Kitamoto, Shunji, Leutenegger, Maurice A., Maeda, Yoshitomo, McCammon, Dan, Miko, Joseph J., Mizumoto, Misaki, Okajima, Takashi, Okamoto, Atsushi, Paltani, Stephane, Porter, Frederick S., Sato, Kosuke, Sato, Toshiki, Sawada, Makoto, Shinozaki, Keisuke, Shipman, Russell, Shirron, Peter J., Sneiderman, Gary A., Soong, Yang, Szymkiewicz, Richard, Szymkowiak, Andrew E., Takei, Yoh, Tamura, Keisuke, Tsujimoto, Masahiro, Uchida, Yuusuke, Wasserzug, Stephen, Witthoeft, Michael C., Wolfs, Rob, Yamada, Shinya, and Yasuda, Susumu

Published
2022
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31. Pre- and post-launch operation of the soft x-ray spectrometer Resolve on board the XRISM satellite

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Sato, Kosuke, Ishisaki, Yoshitaka, Kelley, Richard L., Awaki, Hisamitsu, Balleza, Jesus C., Barnstable, Kim R., Bialas, Thomas G., Boissay-Malaquin, Rozenn, Brown, Gregory V., Canavan, Edgar R., Cumbee, Renata S., Carnahan, Timothy M., Chiao, Meng P., Comber, Brian J., Costantini, Elisa, den Herder, Jan-Willem, Dercksen, Johannes, de Vries, Cor, DiPirro, Michael J., Eckart, Megan E., Ezoe, Yuichiro, Ferrigno, Carlo, Fujimoto, Ryuichi, Gorter, Nathalie, Graham, Steven M., Grim, Martin, Hartz, Leslie S., Hayakawa, Ryota, Hayashi, Takayuki, Hell, Natalie, Hoshino, Akio, Ichinohe, Yuto, Ishi, Daiki, Ishida, Manabu, Ishikawa, Kumi, James, Bryan L., Kanemaru, Yoshiaki, Kenyon, Steven J., Kilbourne, Caroline A., Kimball, Mark O., Kitamoto, Shunji, Leutenegger, Maurice A., Maeda, Yoshitomo, McCammon, Dan, McLaughlin, Brian J., Miko, Joseph J., van der Meer, Erik, Mizumoto, Misaki, Okajima, Takashi, Okamoto, Atsushi, Paltani, Stéphane, Porter, Frederick S., Reichenthal, Lillian S., Sato, Toshiki, Sato, Yoichi, Sawada, Makoto, Shinozaki, Keisuke, Shipman, Russell, Shirron, Peter J., Sneiderman, Gary A., Soong, Yang, Szymkiewicz, Richard, Szymkowiak, Andrew E., Takei, Yoh, Takeo, Mai, Tamba, Tsubasa, Tamura, Keisuke, Tsujimoto, Masahiro, Uchida, Yuusuke, Wasserzug, Stephen, Witthoeft, Michael C., Wolfs, Rob, Yamada, Shinya, Yasuda, Susumu, and Yoshida, Seiji

Published
2024
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32. Strategies for the in-orbit gain tracking using the modulated x-ray sources for the Resolve microcalorimeter spectrometer on XRISM

Author

den Herder, Jan-Willem A., Nikzad, Shouleh, Nakazawa, Kazuhiro, Sawada, Makoto, Cumbee, Renata, de Vries, Cor, Eckart, Megan E., Fujimoto, Ryuichi, Ishisaki, Yoshitaka, Kilbourne, Caroline A., Kitamoto, Shunji, Leutenegger, Maurice A., Porter, Frederick S., Shipman, Russell F., Takei, Yoh, and Tsujimoto, Masahiro

Published
2024
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34. Photouncaging Nanoparticles for MRI and Fluorescence Imaging in Vitroand in Vivo

Author

Shibu, Edakkattuparambil S., Ono, Kenji, Sugino, Sakiko, Nishioka, Ayami, Yasuda, Akikazu, Shigeri, Yasushi, Wakida, Shin-ichi, Sawada, Makoto, and Biju, Vasudevanpillai

Abstract

Multimodal and multifunctional nanomaterials are promising candidates for bioimaging and therapeutic applications in the nanomedicine settings. Here we report the preparation of photouncaging nanoparticles with fluorescence and magnetic modalities and evaluation of their potentials for in vitroand in vivobioimaging. Photoactivation of such bimodal nanoparticles prepared using photouncaging ligands, CdSe/ZnS quantum dots, and super paramagnetic iron oxide nanoparticles results in the systematic uncaging of the particles, which is correlated with continuous changes in the absorption, mass and NMR spectra of the ligands. Fluorescence and magnetic components of the bimodal nanoparticles are characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and elemental analyses using energy dispersive X-ray (EDX) spectroscopy and X-ray photoelectron spectroscopy (XPS). Bioconjugation of the nanoparticles with peptide hormones renders them with biocompatibility and efficient intracellular transport as seen in the fluorescence and MRI images of mouse melanoma cells (B16) or human lung epithelial adenocarcinoma cells (H1650). Biocompatibility of the nanoparticles is evaluated using MTT cytotoxicity assays, which show cell viability over 90%. Further, we combine MRI and NIR fluorescence imaging in C57BL/6 (B6) mice subcutaneously or intravenously injected with the photouncaging nanoparticles and follow the in vivofate of the nanoparticles. Interestingly, the intravenously injected nanoparticles initially accumulate in the liver within 30 min post injection and subsequently clear by the renal excretion within 48 h as seen in the time-dependent MRI and fluorescence images of the liver, urinary bladder, and urine samples. Photouncaging ligands such as the ones reported in this article are promising candidates for not only the site-specific delivery of nanomaterials-based contrast agents and drugs but also the systematic uncaging and renal clearance of nanomaterials after the desired in vivoapplication.

Published
2024
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41. Photosensitizer-singlet oxygen sensor conjugated silica nanoparticles for photodynamic therapy and bioimaging.

Author

Sobhanan J, Ono K, Okamoto T, Sawada M, Weiss PS, and Biju V

Abstract

Intracellular singlet oxygen ( 1 O 2 ) generation and detection help optimize the outcome of photodynamic therapy (PDT). Theranostics programmed for on-demand phototriggered 1 O 2 release and bioimaging have great potential to transform PDT. We demonstrate an ultrasensitive fluorescence turn-on sensor-sensitizer-RGD peptide-silica nanoarchitecture and its 1 O 2 generation-releasing-storing-sensing properties at the single-particle level or in living cells. The sensor and sensitizer in the nanoarchitecture are an aminomethyl anthracene (AMA)-coumarin dyad and a porphyrin or CdSe/ZnS quantum dots (QDs), respectively. The AMA in the dyad quantitatively quenches the fluorescence of coumarin by intramolecular electron transfer, the porphyrin or QD moiety generates 1 O 2, and the RGD peptide facilitates intracellular delivery. The small size, below 200 nm, as verified by scanning electron microscopy and differential light scattering measurements, of the architecture within the 1 O 2 diffusion length enables fast and efficient intracellular fluorescence switching by the tandem ultraviolet (UV)-visible or visible-near-infrared (NIR) photo-triggering. While the red emission and 1 O 2 generation by the porphyrin are continually turned on, the blue emission of coumarin is uncaged into 230-fold intensity enhancement by on-demand photo-triggering. The 1 O 2 production and release by the nanoarchitecture enable spectro-temporally controlled cell imaging and apoptotic cell death; the latter is verified from cytotoxic data under dark and phototriggering conditions. Furthermore, the bioimaging potential of the TCPP-based nanoarchitecture is examined in vivo in B6 mice., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Published
2023
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