Observation of machined surface and subsurface structure of hinoki (Chamaecyparis obtusa) produced in slow-speed orthogonal cutting using X-ray computed tomography

First online: 01 January 2015X-ray computed tomography (CT) was applied to non-destructive observation of machined surface and subsurface structure of hinoki (Chamaecyparis obtusa) produced in slow-speed orthogonal cutting. The cutting experiments were conducted under several cutting conditions and the chip formations were observed with a high-speed camera to be classified into four chip types. The difference in the quality of the machined surfaces produced in four types of chip formation was investigated. During type 0 chip formation, the workpiece was cut almost exactly at the path of the cutting edge, so no deformation was found on and beneath the machined surface. During type I chip formation, the direction of the fore-split, which is dependent on the arrangement of cells, determined the machined surface. During type II chip formation, the cutting tool sometimes tore part of the workpiece below the path of the cutting edge and the tore part was then compressed by the tool, remaining on the machined surface. During type III chip formation, part of the workpiece above the path of the cutting edge was compressed by the tool, instead of being removed as a chip, so the compression occurred in wide area. The relationship between the formation of the machining defects such as torn grain or the compressed cells and the way chip is separated, deformed, or removed was clarified in this study

“youxian ci”(遊仙詞) of Liu Yong － focus on“Wushan yi duan yun(巫山一段雲)”－

北宋の大詞人柳永は、詞という文学ジャンルに様々な新しい主題を取り込んだ。そのうちの一つに、遊仙」と呼ばれる一主題がある。本稿では最初に、遊仙の主題を以て詠まれた柳永の「巫山一段雲」五首が、どのような内容をもつものであるか、簡単な訳注を附して解説する。その上で、柳永の遊仙詞が中国古代遊仙文学の流れの中の、どこに位置づけることが出来るのかを考えていく。唐五代までの遊仙文学は、「現実に対する不満・諷刺」「国家・君主に対する言祝ぎ」をその二大潮流とする。柳永の「巫山一段雲」はどちらかと言えば後者に傾倒するが、人の長寿を祝するという側面がより強く、さらに女仙がしばしば登場する所が特徴的といえる。南宋以後、詞の分野には自分や身近な人々の誕生日を祝う「寿詞」というジャンルが確立するが、その先駆けとなるのが柳永のこれらの詞であり、しかも内容的に一つの典型を作ったということができる。また、柳永が「巫山一段雲」という詞牌を用いて遊仙を詠ったことが、金代以後の全真教道士たちの作詞に強い影響を与えたと考えられる。柳永の遊仙詞は、従来あまり注目されることがなかったが、このような金朝や南宋以後の詞壇に対する影響は、決して看過してよいものではない

Hemostatic Control with Gelatin Sponge and Quantum Molecular Resonance Coagulation in a Case of Glomus Tympanicum

Surgical removal of tumor is the primary treatment of choice for glomus tympanicum (GT). However, because the tumor has abundant blood flow, bleeding control is crucial, and preoperative embolization may be performed. Here, we report the case of a 46-year-old female who visited our hospital with a complaint of right pulsatile tinnitus. A red pulsatile mass was found in the right tympanic cavity, and she was diagnosed with class B1 GT and subsequently underwent surgical treatment. We judged that bleeding could be controlled by intratympanic cavity manipulation alone and decided to perform transmeatal tumor resection without preoperative arterial embolization. After creating a tympanomeatal flap and performing an atticotomy, some pieces of Spongel® were inserted between the tumor and the tympanic wall. The Spongel® absorbed the blood and created a space between the tumor and tympanic wall, which allowed for the insertion of the tip of the Vesalius® handpiece to coagulate the tumor. The coagulation caused the tumor to shrink, thereby widening the space and allowing for further resection. Although the surgical manipulation caused bleeding, complete resection was achieved by the application of Spongel® and coagulation with Vesalius®. Since the tip of the Vesalius® was not burned, hemostasis was successfully achieved, and the operation proceeded while maintaining a clear field of view. There was little bleeding and no postoperative complications. The patient was discharged on the sixth postoperative day. One year after surgery, pure tone audiometry showed no change in the level of bone conduction. Spongel® and Vesalius® are useful tools that allow to safely perform surgeries even in narrow spaces such as the tympanic cavity

Strategies to enhance the excitation energy-transfer efficiency in a light-harvesting system using the intra-molecular charge transfer character of carotenoids

Fucoxanthin is a carotenoid that is mainly found in light-harvesting complexes from brown algae and diatoms. Due to the presence of a carbonyl group attached to polyene chains in polar environments, excitation produces an excited intra-molecular charge transfer. This intra-molecular charge transfer state plays a key role in the highly efficient (∼95%) energy-transfer from fucoxanthin to chlorophyll a in the light-harvesting complexes from brown algae. In purple bacterial light-harvesting systems the efficiency of excitation energy-transfer from carotenoids to bacteriochlorophylls depends on the extent of conjugation of the carotenoids. In this study we were successful, for the first time, in incorporating fucoxanthin into a light-harvesting complex 1 from the purple photosynthetic bacterium, Rhodospirillum rubrum G9+ (a carotenoidless strain). Femtosecond pump-probe spectroscopy was applied to this reconstituted light-harvesting complex in order to determine the efficiency of excitation energy-transfer from fucoxanthin to bacteriochlorophyll a when they are bound to the light-harvesting 1 apo-proteins

Polycomb Repressive Complex 2 Regulates Normal Hematopoietic Stem Cell Function in a Developmental-Stage-Specific Manner

SummaryRecent studies point to a pivotal role of Polycomb repressive complex 2 (PRC2) in stem cell function and cancer. Loss-of-function approaches targeting individual PRC2 subunits have, however, generated findings that are difficult to reconcile. Here, we prevent assembly of both Ezh1- and Ezh2-containing PRC2 complexes by conditional deletion of Eed, a core subunit, and assess hematopoiesis. We find that deletion of Eed exhausts adult bone marrow hematopoietic stem cells (HSCs), although fetal liver HSCs are produced in normal numbers. Eed-null neonatal HSCs express HSC signature genes but are defective in maintenance and differentiation. Comparative gene expression profiling revealed that neonatal and adult HSCs lacking Eed upregulated gene sets of conflicting pathways. Deletion of Cdkn2a, a PRC2 target gene, in Eed-null mice enhances hematopoietic stem/progenitor cell (HSPC) survival but fails to restore HSC functions. Taken together, our findings define developmental-stage-specific requirements for canonical PRC2 complexes in normal HSC function

Specific gene expression in unmyelinated dorsal root ganglion neurons in nonhuman primates by intra-nerve injection of AAV 6 vector

霊長類においてウイルスベクターを用いた痛覚神経への遺伝子導入に成功 --神経障害性疼痛治療への応用に期待--. 京都大学プレスリリース. 2021-08-12.Adeno-associated virus 6 has been proposed as a potential vector candidate for specific gene expression in pain-related dorsal root ganglion neurons, but this has not been confirmed in nonhuman primates. The aim of our study was to analyze the transduction efficiency and target specificity of this viral vector in the common marmoset by comparing with those in the rat. When green fluorescent protein-expressing serotype-6 vector was injected into the sciatic nerve, the efficiency of gene expression in dorsal root ganglion neurons was comparable in both species. We found that the serotype-6 vector was largely specific to the pain-related ganglion neurons in the marmoset as well as in the rat, whereas the serotype-9 vector resulted in contrasting effects in the two species. Neither AAV6 nor AAV9 resulted in DRG toxicity when administered via the sciatic nerve, suggesting this as a safer route of sensory nerve transduction than the currently used intrathecal or intravenous administrative routes. Furthermore, the adeno-associated virus 6 vector could be an optimal serotype for gene therapy for human chronic pain that has minimal effect on other somatosensory functions of dorsal root ganglion neurons

Successfully Treated Pneumatosis Cystoides Intestinalis with Pneumoperitoneum Onset in a Patient Administered α-glucosidase Inhibitor

An 80-year-old woman, who had been administered α-glucosidase inhibitor for diabetes, was brought to the hospital with the sensation of abdominal fullness and pain. Abdominal computed tomography indicated pneumatosis cystoides intestinalis (PCI) in the small intestinal wall, with free air within the abdomen. A blood examination showed no increases in white blood cells or C-reactive protein level. The patientʼs condition improved with conservative therapy. PCI with pneumoperitoneum induced by α-glucosidase inhibitor is rare, with only 27 cases (excluding the present case) reported in Japan to date. In PCI with pneumoperitoneum, differentiation from gastrointestinal perforation is important and following the clinical symptoms over time is vital