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2. Dynamic optical path provisioning for alien access links: architecture, demonstration, and challenges

Author

Nishizawa, Hideki, Sasai, Takeo, Inoue, Takeru, Anazawa, Kazuya, Mano, Toru, Kitamura, Kei, Sone, Yoshiaki, Inui, Tetsuro, and Takasugi, Koichi

Subjects
Computer Science - Networking and Internet Architecture, Electrical Engineering and Systems Science - Signal Processing, Electrical Engineering and Systems Science - Systems and Control
Abstract

With the spread of Data Center Interconnect (DCI) and local 5G, there is a growing need for dynamically established connections between customer locations through high-capacity optical links. However, link parameters such as signal power profile and amplifier gains are often unknown and have to be measured by experts, preventing dynamic path provisioning due to the time-consuming manual measurements. Although several techniques for estimating the unknown parameters of such alien access links have been proposed, no work has presented architecture and protocol that drive the estimation techniques to establish an optical path between the customer locations. Our study aims to automatically connect customer-owned transceivers via alien access links with optimal quality of transmission (QoT). We first propose an architecture and protocol for cooperative optical path design between a customer and carrier, utilizing a state-of-the-art technique for estimating link parameters. We then implement the proposed protocol in a software-defined network (SDN) controller and white-box transponders using an open API. The experiments demonstrate that the optical path is dynamically established via alien access links in 137 seconds from the transceiver's cold start. Lastly, we discuss the QoT accuracy obtained with this method and the remaining issues., Comment: 6 pages, 5 figures, 1 table

Published
2022

16. Growth patterns of facial muscles at the angle of the mouth: A histological study using midterm and near‐term human fetuses.

Author

Takahashi, Sakiko, Ishizuka, Satoshi, Kitamura, Kei, Yang, Tianyi, Abe, Shin‐ichi, Murakami, Gen, and Rodríguez‐Vázquez, Jose Francisco

Subjects
CENTRAL nervous system, FETUS, ELEVATORS, ANGLES, FRICTION
Abstract

At the angle of the mouth, spoke‐like muscle bundles converge at the "modiolus," which is believed to appear in utero. The aim of this study was to investigate the growth of the modiolus histologically. We studied frontal histological sections of the face from 12 midterm and six near‐term fetuses. At midterm, a convergence of the levator anguli oris (LAOM) and depressor anguli oris (DAOM) was frequently present, and another convergence of the LAOM with the platysma (PM) or orbicularis oris (OOM) was also often evident. At near‐term, muscle fiber merging or interdigitation was classified into nine combinations, five of which were frequently seen: LAOM‐PM, LAOM‐DAOM, zygomaticus major (ZMM)‐orbicularis oris (OOM), buccinator (BM)‐LAOM, and BM‐PM. These combinations existed at slightly different depths and/or sites, thus allowing the angle of the mouth to receive multiple muscles. Notably, tissues interposed between the muscle fibers were limited to a thin epimysium at each crossing or interdigitation. Therefore, the LAOM, DAOM, OOM, BM, and PM appear to form a basic configuration at birth, but the development and growth were much delayed than the classical description. The modiolus is not a specific fibromuscular structure but simply represents a cluster of muscle convergence sites. Even at meeting between an elevator and depressor, a specific fibrous structure seems unlikely to connect the epimysium for the muscle convergence. Instead, the central nervous system appears to regulate the activity of related muscles to minimize tension or friction stress at the meeting site. [ABSTRACT FROM AUTHOR]

Published
2024
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17. Ontogenic transformation of the ankle from the initial mediolateral arrangement of the calcaneus and talus: A histological study of human embryos and early fetuses.

Author

Kim, Ji Hyun, Ishizuka, Satoshi, Kitamura, Kei, Murakami, Gen, Rodríguez‐Vázquez, José Francisco, Abe, Shin‐ichi, and Kasahara, Masataka

Subjects
TARSAL bones, ACHILLES tendon, ANKLE joint, BIPEDALISM, HUMAN embryos
Abstract

The human calcaneus is robust and provides a prominent heel for effective bipedal locomotion, although the adjacent talus has no muscle attachments. However, there is incomplete information about the morphological changes in these prominent bones during embryo development. We examined serial histological sections of 23 human embryos and early‐term fetuses (approximately 5–10 weeks' gestational age [GA]). At a GA of 5 weeks, the precartilage talus was parallel to and on the medial side of the calcaneus, which had a prolate spheroid shape and consisted of three masses. At a GA of 6 weeks, the cartilaginous talus extended along the proximodistal axis, and the tuber calcanei became long and bulky, with a small sustentaculum talus at the "distal" side. At a GA of 6 to 8 weeks, the sustentaculum had a medial extension below the talus so that the talus "rode over" the calcaneus. In contrast, the talus had a more complex shape, depending on the growth of adjacent bones. At a GA of 9 to 10 weeks, the talus was above the calcaneus, but the medial part still faced the plantar subcutaneous tissue because of the relatively small sustentaculum. Therefore, the final morphology appeared after an additional several weeks. Muscle activity seemed to facilitate growth of the tuber calcanei, but growth of the other parts of calcaneus, including the sustentaculum, seemed to depend on active proliferation at the different sites of cartilage. Multiple tendons and ligaments seemed to fix the talus so that it remained close to the calcaneus. [ABSTRACT FROM AUTHOR]

Published
2024
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21. Development and growth of the temporal fascia: a histological study using human fetuses

Author

Kitamura, Kei, Ishizuka, Satoshi, Kim, Ji Hyun, Yamamoto, Hitoshi, Murakami, Gen, Rodríguez Vázquez, José Francisco, Abe, Shinichi, Kitamura, Kei, Ishizuka, Satoshi, Kim, Ji Hyun, Yamamoto, Hitoshi, Murakami, Gen, Rodríguez Vázquez, José Francisco, and Abe, Shinichi

Abstract

The temporal fascia is a double lamina sandwiching a thick fat layer above the zygomatic bony arch. To characterize each lamina, their developmental processes were examined in fetuses. We observed histological sections from 22 half-heads of 10 mid-term fetuses at 14–18 weeks (crown-rump length, 95–150 mm) and 12 near-term fetuses at 26–40 weeks (crown-rump length, 215–334 mm). The superficial lamina of the temporal fascia was not evident at mid-term. Instead, a loose subcutaneous tissue was attached to the thin, deep lamina of the temporal fascia covering the temporalis muscle. At near-term, the deep lamina became thick, while the superficial lamina appeared and exhibited several variations: i) a mono-layered thick membrane (5 specimens); ii) a multi-layered membranous structure (6) and; iii) a cluster of independent thick fasciae each of which were separated by fatty tissues (1). In the second and third patterns, fatty tissue between the two laminae was likely to contain longitudinal fibrous bands in parallel with the deep lamina. Varying proportions of the multi-layered superficial lamina were not attached to the zygomatic arch, but extended below the bony arch. Whether or not lobulation or septation of fatty tissues was evident was not dependent on age. The deep lamina seemed to develop from the temporalis muscle depending on the muscle contraction. In contrast, the superficial lamina developed from subcutaneous collagenous bundles continuous to the cheek. Therein, a difference in development was clearly seen between two categories of the fasciae., Universidad Complutense de Madrid, Tokyo Dental College, Depto. de Anatomía y Embriología, Fac. de Medicina, TRUE, pub

Published
2024

28. Dynamic Optical Path Provisioning for Alien Access Links: Architecture, Demonstration, and Challenges

Author

Nishizawa, Hideki, Sasai, Takeo, Inoue, Takeru, Anazawa, Kazuya, Mano, Toru, Kitamura, Kei, Sone, Yoshiaki, Inui, Tetsuro, and Takasugi, Koichi

Subjects
Networking and Internet Architecture (cs.NI), Signal Processing (eess.SP), FOS: Computer and information sciences, Computer Science - Networking and Internet Architecture, Computer Networks and Communications, FOS: Electrical engineering, electronic engineering, information engineering, Systems and Control (eess.SY), Electrical Engineering and Systems Science - Signal Processing, Electrical and Electronic Engineering, Electrical Engineering and Systems Science - Systems and Control, Computer Science Applications
Abstract

With the spread of Data Center Interconnect (DCI) and local 5G, there is a growing need for dynamically established connections between customer locations through high-capacity optical links. However, link parameters such as signal power profile and amplifier gains are often unknown and have to be measured by experts, preventing dynamic path provisioning due to the time-consuming manual measurements. Although several techniques for estimating the unknown parameters of such alien access links have been proposed, no work has presented architecture and protocol that drive the estimation techniques to establish an optical path between the customer locations. Our study aims to automatically connect customer-owned transceivers via alien access links with optimal quality of transmission (QoT). We first propose an architecture and protocol for cooperative optical path design between a customer and carrier, utilizing a state-of-the-art technique for estimating link parameters. We then implement the proposed protocol in a software-defined network (SDN) controller and white-box transponders using an open API. The experiments demonstrate that the optical path is dynamically established via alien access links in 137 seconds from the transceiver's cold start. Lastly, we discuss the QoT accuracy obtained with this method and the remaining issues., 6 pages, 5 figures, 1 table

Published
2023
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32. Sardine procalcitonin amino-terminal cleavage peptide has a different action from calcitonin and promotes osteoblastic activity in the scales of goldfish

Author

Kase, Yoichi, Ikari, Takahiro, Sekiguchi, Toshio, Sato, Masayuki, Ogiso, Shouzo, Kawada, Tsuyoshi, Matsubara, Shin, Satake, Honoo, Sasayama, Yuichi, Endo, Masato, Kitamura, Kei-ichiro, Hattori, Atsuhiko, Watanabe, Takushi X., Maruyama, Yusuke, Watanabe, Yoshinari, Funahashi, Hisayuki, Kambegawa, Akira, and Suzuki, Nobuo

Published
2017
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37. Chronological Changes in the Expression and Localization of Sox9 between Achilles Tendon Injury and Functional Recovery in Mice

Author

Watanabe, Genji, primary, Yamamoto, Masahito, additional, Taniguchi, Shuichirou, additional, Sugiyama, Yuki, additional, Hirouchi, Hidetomo, additional, Ishizuka, Satoshi, additional, Kitamura, Kei, additional, Mizoguchi, Toshihide, additional, Takayama, Takashi, additional, Hayashi, Katsuhiko, additional, and Abe, Shinichi, additional

Published
2023
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41. Topohistology of the cranial nerves IX–XII at the cranial base and upper parapharyngeal space: A histological study using human fetuses

Author

Ho Cho, Kwang, Honkura, Yohei, Kim, Ji Hyun, Hayashi, Shogo, Kitamura, Kei, Murakami, Gen, Rodríguez Vázquez, José Francisco, Ho Cho, Kwang, Honkura, Yohei, Kim, Ji Hyun, Hayashi, Shogo, Kitamura, Kei, Murakami, Gen, and Rodríguez Vázquez, José Francisco

Abstract

The topographical relationships among the lower cranial nerves, internal carotid artery (ICA), and internal jugular vein (IJV) in the upper parapharyngeal neurovascular bundle remain obscure. Thus, details of the anatomy were examined in human fetus histology. We observed the horizontal histological sections from 20 midterm (9–18 weeks) and 12 near-term (28–40 weeks) fetuses. At the external skull base, the glossopharyngeal nerve crosses the anterior aspect of the IJV to reach the medially located Hyrtl's fissure in the petrous temporal bone. The nerve crossed the anterior aspect of the ICA medially near or below the first cervical nerve root. Below the hypoglossal nerve canal, the accessory nerve crosses the anterior or posterior aspects of the IJV and moves laterally. During the half-spiral course, the hypoglossal nerve was tightly attached to the posterolateral–anterior aspects of the vagus nerve and surrounded by a common nerve sheath. The glossopharyngeal ganglia sometimes extended inferiorly to the level of the hypoglossal nerve canal but were absent along the inferior course. The inferior vagal ganglion rarely extends above the occipital condyle. The superior cervical sympathetic ganglion occasionally extends above the first cervical nerve root. The IJV (or ICA) descends to the lateral (or medial) margins of the parapharyngeal neurovascular bundle. The glossopharyngeal (or accessory) nerve crosses the ICA (or IJV) to exit the bundle at the base of the skull (or below the hypoglossal nerve canal). The glossopharyngeal and vagus inferior ganglia differ at each site., Wonkwang University, Depto. de Anatomía y Embriología, Fac. de Medicina, TRUE, pub

Published
2023

42. Iterative Assembly of Chiral Alcohols Utilizing CMMP-Mediated Mitsunobu Reactions.

Author

Kitamura, Kei, Ise, Saki, Tsunoda, Tetsuto, and Kaku, Hiroto

Subjects
*MITSUNOBU reaction, *CHEMICAL synthesis, *ORGANIC synthesis, *BIOACTIVE compounds, *CHEMICAL properties
Abstract

The given text is a scientific research article that discusses the use of the Mitsunobu reaction for synthesizing chiral alcohols. The authors developed stabilized phosphorane reagents to overcome the limitation of low acidity in the reaction. They demonstrate the iterative assembly of chiral alcohols using these reagents, which can be used to synthesize biologically active compounds with multiple stereogenic centers. The article provides detailed information on the synthesis and characterization of various chemical compounds, including their physical and chemical properties, as well as the experimental procedures used. This information can be valuable for researchers studying organic chemistry and chemical synthesis. [Extracted from the article]

Published
2024
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48. The Microscopic Structure of the Root Canal Morphology of the Distobuccal Root of the Maxillary First Molar in Japanese People: A Micro-Computed Tomography Study

Author

Yamada, Masashi, primary, Matsunaga, Satoru, additional, Kasahara, Norio, additional, Kitamura, Kei, additional, Suzuki, Megumi, additional, Tamiya, Yoshiki, additional, Takeuchi, Yuki, additional, Takahashi, Akihiro, additional, Yamamoto, Hitoshi, additional, Abe, Shinichi, additional, and Furusawa, Masahiro, additional

Published
2023
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