17 research outputs found

    Genetic diversity and population structure in the Ryukyu flying fox inferred from remote sampling in the Yaeyama archipelago

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    The Ryukyu flying fox (Pteropus dasymallus) is distributed throughout the island chain spanning across southern Japan, Taiwan, and possibly the Philippines. Although P. dasymallus is listed as VU (vulnerable) in the IUCN Red List, only few genetic works have been conducted to support its conservation. In this study we analyzed 19 markers (mtDNA haplotypes and 18 microsatellite markers) to evaluate genetic diversity and investigate the genetic structure of this species. mtDNA analysis was conducted with 142 DNA remote samples, mostly from faeces, and wing tissues collected on eight islands (Miyako, Ishigaki, Kohama, Kuroshima, Hateruma, Taketomi, Iriomote, Yonaguni). 39 haplotypes were identified in 526bp of the control region, and haplotype network showed no clear genetic structure. Microsatellite analysis was also conducted with 155 samples collected on six islands (Miyako, Ishigaki, Kohama, Taketomi, Iriomote, Yonaguni). It showed that the Yonaguni population exhibits low genetic diversity, high inbreeding, and clear genetic differentiation from other populations. Gene flow between Ishigaki and Miyako through small stepstone islands might be preventing inbreeding of the Miyako population. We provide for the first time indirect proof of long-distance inter-island dispersal in the Ryukyu flying fox and revealed genetic diversity, gene flow and genetic differentiation among the archipelago's populations. These results will be useful for delineating conservation units and designing specific conservation policies for each island based on metapopulation genetic structure

    Non-volatile optical phase shift in ferroelectric hafnium zirconium oxide

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    A non-volatile optical phase shifter is a critical component for enabling large-scale, energy-efficient programmable photonic integrated circuits (PICs) on a silicon (Si) photonics platform. While ferroelectric materials like BaTiO3 offer non-volatile optical phase shift capabilities, their compatibility with complementary metal-oxide-semiconductor (CMOS) fabs is limited. Hence, the search for a novel CMOS-compatible ferroelectric material for non-volatile optical phase shifting in Si photonics is of utmost importance. Hafnium zirconium oxide (HZO) is an emerging ferroelectric material discovered in 2011, which exhibits CMOS compatibility due to the utilization of high-k dielectric HfO2 in CMOS transistors. Although extensively studied for ferroelectric transistors and memories, its application in photonics remains relatively unexplored. Here, we show the optical phase shift induced by ferroelectric HZO deposited on a SiN optical waveguide. We observed a negative change in refractive index at a 1.55 um wavelength in the pristine device regardless of the direction of an applied electric filed. We achieved approximately pi phase shift in a 4.5-mm-long device with negligible optical loss. The non-volatile multi-level optical phase shift was confirmed with a persistence of > 10000 s. This phase shift can be attributed to the spontaneous polarization within the HZO film along the external electric field. We anticipate that our results will stimulate further research on optical nonlinear effects, such as the Pockels effect, in ferroelectric HZO. This advancement will enable the development of various devices, including high-speed optical modulators. Consequently, HZO-based programmable PICs are poised to become indispensable in diverse applications, ranging from optical fiber communication and artificial intelligence to quantum computing and sensing

    Line operators on S^1xR^3 and quantization of the Hitchin moduli space

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    We perform an exact localization calculation for the expectation values of Wilson-'t Hooft line operators in N=2 gauge theories on S^1xR^3. The expectation values are naturally expressed in terms of the complexified Fenchel-Nielsen coordinates, and form a quantum mechanically deformed algebra of functions on the associated Hitchin moduli space by Moyal multiplication. We propose that these expectation values are the Weyl transform of the Verlinde operators, which act on Liouville/Toda conformal blocks as difference operators. We demonstrate our proposal explicitly in SU(N) examples.Comment: 58 pages; v.2 minor corrections, references added; v.3 corrections corresponding to JHEP erratu

    ヨナオシ ノート 2020ネンド フユ

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    「世直し研究会」は、2006年4月から2016年3月まで大阪大学コミュニケーションデザインセンターにおいて開催された「現場力研究会」の後継組織として2018 年4月25日に誕生し、通算で201回を数えます。月1回水曜日に大阪大学COデザインセンターで開催され、世の中の理不尽や不条理から目を逸らすことなく、「世」のあるべき姿を問いつつ、具体的な現場での課題に取り組む力を養い、「世直し」へと繋げていくことが目指されています。今回掲載したこの「世直し」ノオト(2020年度・冬)は、研究会に集う大学内外の参加者が、研究会での対話をもとに考えて綴った「ノオト(notes)」の第6弾にあたります。すなわち第26回から第31回までの研究会(2020 年8月~2021 年1月)における対話から編み出された10 編のエッセイになります。この期間に取り上げたテーマは以下の通りです。第26回(2020年8月26日) 「戦争と平和」【オンライン開催】第27回(2020年9月30日) 「世直し」うた会【オンライン開催】第28回(2020年10月28日 観劇を通して世直しを考える ~くるみざわしん作『同郷同年』~第29回(2020年11月25日) 世直し研究会メンバーの新著紹介【オンライン開催】熊野以素『“奇天烈”議会奮闘記―市民派女性市議の8 年間―』(東銀座出版社、2020年9月)北村敏泰『揺らぐいのち―生老病死の現場に寄り添う聖たち―』(晃洋書房、2020年11月)コロナ禍にあって、上記の研究会のほとんどがオンライン開催となりました。「世直し」ノオト(2020年度・夏)では「今、コロナ禍で」というテーマを取り上げましたが、本ノオトもこの状況に鑑みて、対面機会の減少が与える影響や、新たな人との接し方の可能性、今こそ求められる力ある言葉についてなど、コミュニケーションに関わる問いを投げかけたエッセイが多く見られます

    ヨナオシ ノート 2021ネンド ナツ 

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    「世直し研究会」は、2006年4月から2016年3月まで大阪大学コミュニケーションデザイン・センターにおいて開催された「現場力研究会」の後継組織として2018年4月25日に誕生し、通算で207回を数えます。月1回大阪大学COデザインセンターで開催され、世の中の理不尽や不条理から目を逸らすことなく、「世」のあるべき姿を問いつつ、具体的な現場での課題に取り組む力を養い、「世直し」へと繋げていくことが目指されています。今回掲載したこの「世直し」ノオト(2021 年度・夏)は、研究会に集う大学内外の参加者が、研究会での対話をもとに考えて綴った「ノオト(notes)」の第7 弾にあたります。すなわち第32回から第37回までの研究会(2021年2月~2021年7月)における対話から編み出された10編のエッセイになります。この期間は読書会を中心に、下記の内容を行いました。第32回(2021年2月24日)読書会[課題図書]ガブリエル・ガルシア=マルケス著『コレラの時代の愛』(木村榮一訳, 新潮社、2006年)【オンライン開催】第33回(2021年3月24日)環境でお金を受け取る仕組み―「生態系サービスへの支払い」と関わるコスタリカの先住民居住区とその住民についての一考察―【オンライン開催】第34回(2021年4月28日)読書会[課題図書]ナディア・ムラド著『THE LAST GIRL―イスラム国に囚われ、闘いを続ける女性の物語―』(東洋館出版社、2018年)【オンライン開催】第35回(2021年5月24日)読書会[課題図書]澁谷智子著『ヤングケアラーわたしの語り:子どもや若者が経験した家族のケア・介護』(生活書院、2020年)【オンライン開催】第36回(2020年6月23日)読書会[課題図書1]中井久夫著『災害がほんとうに襲った時―阪神淡路大震災50日間の記録』(みすず書房、2011年)[課題図書2]中井久夫著『復興の道なかばで―阪神淡路大震災一年の記録』(みすず書房、2011年)【オンライン開催】第37回(2021年7月21日)「世直し」ノオト(2021年度・夏)合評会【オンライン開催】※第1回から第31回までの研究会テーマは、Co* Design 第6号から第10号に掲載の「世直し」ノオトをご覧ください

    Differential Metabolic Responses to Adipose Atrophy Associated with Cancer Cachexia and Caloric Restriction in Rats and the Effect of Rikkunshito in Cancer Cachexia

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    Despite the similar phenotypes, including weight loss, reduction of food intake, and lower adiposity, associated with caloric restriction (CR) and cancer cachexia (CC), CC is a progressive wasting syndrome, while mild CR improves whole body metabolism. In the present study, we compared adipose metabolic changes in a novel rat model of CC, mild CR (70% of the food intake of control rats, which is similar to the food consumption of CC rats), and severe CR (30% of the food intake of controls). We show that CC and severe CR are associated with much smaller adipocytes with significantly lower mitochondrial DNA content; but, that mild CR is not. CC and both mild and severe CR similarly upregulated proteins involved in lipolysis. CC also downregulated proteins involved in fatty acid biosynthesis, but mild CR upregulated these. These findings suggest that CC might impair de novo fatty acid biosynthesis and reduce mitochondrial biogenesis, similar to severe CR. We also found that rikkunshito, a traditional Japanese herbal medicine, does not ameliorate the enhanced lipolysis and mitochondrial impairment, but rather, rescues de novo fatty acid biosynthesis, suggesting that rikkunshito administration might have partially similar effects to mild CR

    Low-intensity pulsed ultrasound enhances angiogenesis and ameliorates contractile dysfunction of pressure-overloaded heart in mice

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    <div><p>Introduction</p><p>Chronic left ventricular (LV) pressure overload causes relative ischemia with resultant LV dysfunction. We have recently demonstrated that low-intensity pulsed ultrasound (LIPUS) improves myocardial ischemia in a pig model of chronic myocardial ischemia through enhanced myocardial angiogenesis. In the present study, we thus examined whether LIPUS also ameliorates contractile dysfunction in LV pressure-overloaded hearts.</p><p>Methods and results</p><p>Chronic LV pressure overload was induced with transverse aortic constriction (TAC) in mice. LIPUS was applied to the whole heart three times in the first week after TAC and was repeated once a week for 7 weeks thereafter (n = 22). Animals in the control groups received the sham treatment without LIPUS (n = 23). At 8 weeks after TAC, LV fractional shortening was depressed in the TAC-Control group, which was significantly ameliorated in the TAC-LIPUS group (30.4±0.5 vs. 36.2±3.8%, P<0.05). Capillary density was higher and perivascular fibrosis was less in the LV in the TAC-LIPUS group than in the TAC-Control group. Myocardial relative ischemia evaluated with hypoxyprobe was noted in the TAC-Control group, which was significantly attenuated in the TAC-LIPUS group. In the TAC-LIPUS group, as compared with the control group, mRNA expressions of BNP and collagen III were significantly lower (both P<0.05) and protein expressions of VEGF and eNOS were significantly up-regulated associated with Akt activation (all P<0.05). No adverse effect related to the LIPUS therapy was noted.</p><p>Conclusions</p><p>These results indicate that the LIPUS therapy ameliorates contractile dysfunction in chronically pressure-overloaded hearts through enhanced myocardial angiogenesis and attenuated perivascular fibrosis. Thus, the LIPUS therapy may be a promising, non-invasive treatment for cardiac dysfunction due to chronic pressure overload.</p></div

    Intracellular signaling pathways for the beneficial effects of the LIPUS.

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    <p>The LIPUS therapy ameliorates cardiac contractile dysfunction by enhancing angiogenesis through up-regulation of VEGF, eNOS and p-Akt and attenuating perivascular fibrosis through down-regulation of collagen III in the LV, suppressing the transition from compensated LVH to decompensated HF.</p
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