Poor Prognostic Factors for Surgical Treatment of Spinal Intramedullary Ependymoma (World Health Organization Grade II)

Tsuji Osahiko,Nagoshi Narihito,Ishii Ryota,Nori Satoshi,Suzuki Satoshi,Okada Eijiro,Fujita Nobuyuki,Yagi Mitsuru,Matsumoto Morio,Nakamura Masaya,Watanabe Kota 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.6

Study Design: Single-center retrospective study.Purpose: We aimed to explore the postoperative prognostic factors for spinal intramedullary ependymoma.Overview of Literature: Ependymoma (World Health Organization grade II) is the most frequent intramedullary spinal tumor and is treated by total resection. However, postoperative deterioration of motor function occasionally occurs.Methods: Eighty patients who underwent surgical resection at Keio University and Fujita Health University in Tokyo, Japan between 2003 and 2015 with more than 2 years of follow-up were enrolled. A good surgical result was defined as an improvement in the modified McCormick Scale score by one grade or more or having the same clinical grade as was observed preoperatively. Meanwhile, a poor result was defined as a reduction in the McCormick Scale score of one grade or more or remaining in grade IV or V at final follow-up. Univariate and multivariate logistic regression analyses of the following factors were performed in the two groups: sex, age, preoperative Visual Analog Scale (VAS), tumor location, the extent of tumor resection, hemosiderin caps, cavity length, and tumor length on magnetic resonance imaging.Results: At final follow-up, 15 patients were included in the poor results group and 65 in the good results group. In the univariate analysis, the factors related to poor results were as follows: higher age, preoperative McCormick Scale score severity, higher preoperative VAS, thoracic location, hemosiderin capped, and non-gross total resection (GTR). A multiple logistic regression analysis was conducted and showed that age, worse preoperative McCormick Scale score, and non-GTR were significant factors for poor prognosis.Conclusions: The independent risk factors for motor deterioration after ependymoma resection were age, worse preoperative McCormick Scale score, and non-GTR. Early surgery for patients with even mild neurological disorders could facilitate functional outcomes. These results may contribute to determining the optimal timing of surgery for spinal intramedullary ependymoma.

Long-term stability after multidisciplinary treatment involving maxillary distraction osteogenesis, and sagittal split ramus osteotomy for unilateral cleft lip and palate with severe occlusal collapse and gingival recession: A case report

Satoshi Kokai,Eiji Fukuyama,Susumu Omura,Sachiko Kimizuka,Ikuo Yonemitsu,Koichi Fujita,Takashi Ono 대한치과교정학회 2019 대한치과교정학회지 Vol.49 No.1

In this report, we describe a case involving a 34-year-old woman who showed good treatment outcomes with long-term stability after multidisciplinary treatment for unilateral cleft lip and palate (CLP), maxillary hypoplasia, severe maxillary arch constriction, severe occlusal collapse, and gingival recession. A comprehensive treatment approach was developed with maximum consideration of strong scar constriction and gingival recession; it included minimum maxillary arch expansion, maxillary advancement by distraction osteogenesis using an internal distraction device, and mandibular setback using sagittal split ramus osteotomy. Her post-treatment records demonstrated a balanced facial profile and occlusion with improved facial symmetry. The patient’s profile was dramatically improved, with reduced upper lip retrusion and lower lip protrusion as a result of the maxillary advancement and mandibular setback, respectively. Although gingival recession showed a slight increase, tooth mobility was within the normal physiological range. No tooth hyperesthesia was observed after treatment. There was negligible osseous relapse, and the occlusion remained stable after 5 years of post-treatment retention. Our findings suggest that such multidisciplinary approaches for the treatment of CLP with gingival recession and occlusal collapse help in improving occlusion and facial esthetics without the need for prostheses such as dental implants or bridges; in addition, the results show long-term post-treatment stability.

Ho-doping Effect on the Incommensurate Magnetic Order in La1.88Sr0.12CuO4

Masaki Fujita,Masanori Enoki,Kenji Tsutsumi,Satoshi Iikubo,Kazuyoshi Yamada 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.12

We have performed elastic neutron scattering experiments on the superconductorLa1.85Ho0.03Sr0.12CuO4 to study the effect of substitution of a cation with a large magnetic momentat La site on the static spin correlation. In the Ho-free sample with a hole concentration of 0.12,the spatially-modulated magnetic order is known to be stabilized at temperature below Tspin 30K. In the present Ho-doped sample, we found the appearance of magnetic peaks at (0.5, 0.5 ± 0.119, 0) positions below Tspin 35 K, which is similar to the observation in the pristine sample. Furthermore, the volume-corrected intensities in the Ho-free and Ho-doped samples are comparable,suggesting a negligible effect of Ho-substitution at La sites. These results are quite a contrast tothe huge enhancement of the magnetic intensity and the increase of Tspin by substituting a comparableamounts of magnetic Fe3+ ions onto CuO2 planes. Therefore, the stability of the stripe orderinduced by the cation substitution is sensitive to the site at which the substitution occurs.

A Fair and Efficient Congestion Avoidance Scheme Based on the Minority Game

Kutsuna, Hiroshi,Fujita, Satoshi Korea Information Processing Society 2011 Journal of information processing systems Vol.7 No.3

In this paper, we propose a new congestion control scheme for high-speed networks. The basic idea of our proposed scheme is to adopt a game theory called, "Minority Game" (MG), to realize a selective reduction of the transmission speed of senders. More concretely, upon detecting any congestion, the scheme starts a game among all senders who are participating in the communication. The losers of the game reduce the transmission speed by a multiplicative factor. MG is a game that has recently attracted considerable attention, and it is known to have a remarkable property so that the number of winners converges to a half the number of players in spite of the selfish behavior of the players to increase its own profit. By using this property of MG, we can realize a fair reduction of the transmission speed, which is more efficient than the previous schemes in which all senders uniformly reduce their transmission speed. The effect of the proposed scheme is evaluated by simulation. The result of simulations indicates that the proposed scheme certainly realizes a selective reduction of the transmission speed. It is sufficiently fair compared to other simple randomized schemes and is sufficiently efficient compared to other conventional schemes.

A Fair and Efficient Congestion Avoidance Scheme Based on the Minority Game

Hiroshi Kutsuna,Satoshi Fujita 한국정보처리학회 2011 Journal of information processing systems Vol.7 No.3

Cost-Effective Replication Schemes for Query Load Balancing in DHT-Based Peer-to-Peer File Searches

( Qi Cao ),( Satoshi Fujita ) 한국정보처리학회 2014 Journal of information processing systems Vol.10 No.4

In past few years, distributed hash table (DHT)-based P2P systems have been proven to be a promising way to manage decentralized index information and provide efficient lookup services. However, the skewness of users`` preferences regarding keywords contained in a multi-keyword query causes a query load imbalance that combines both routing and response load. This imbalance means long file retrieval latency that negatively influences the overall system performance. Although index replication has a great potential for alleviating this problem, existing schemes did not explicitly address it or incurred high cost. To overcome this issue, we propose, in this paper, an integrated solution that consists of three replication schemes to alleviate query load imbalance while minimizing the cost. The first scheme is an active index replication that is used in order to decrease routing load in the system and to distribute response load of an index among peers that store replicas of the index. The second scheme is a proactive pointer replication that places location information of each index to a predetermined number of peers for reducing maintenance cost between the index and its replicas. The third scheme is a passive index replication that guarantees the maximum query load of peers. The result of simulations indicates that the proposed schemes can help alleviate the query load imbalance of peers. Moreover, it was found by comparison that our schemes are more cost-effective on placing replicas than PCache and EAD.

Cost-Effective Replication Schemes for Query Load Balancing in DHT-Based Peer-to-Peer File Searches

Cao, Qi,Fujita, Satoshi Korea Information Processing Society 2014 Journal of information processing systems Vol.10 No.4

In past few years, distributed hash table (DHT)-based P2P systems have been proven to be a promising way to manage decentralized index information and provide efficient lookup services. However, the skewness of users' preferences regarding keywords contained in a multi-keyword query causes a query load imbalance that combines both routing and response load. This imbalance means long file retrieval latency that negatively influences the overall system performance. Although index replication has a great potential for alleviating this problem, existing schemes did not explicitly address it or incurred high cost. To overcome this issue, we propose, in this paper, an integrated solution that consists of three replication schemes to alleviate query load imbalance while minimizing the cost. The first scheme is an active index replication that is used in order to decrease routing load in the system and to distribute response load of an index among peers that store replicas of the index. The second scheme is a proactive pointer replication that places location information of each index to a predetermined number of peers for reducing maintenance cost between the index and its replicas. The third scheme is a passive index replication that guarantees the maximum query load of peers. The result of simulations indicates that the proposed schemes can help alleviate the query load imbalance of peers. Moreover, it was found by comparison that our schemes are more cost-effective on placing replicas than PCache and EAD.

A Two-Level Caching Protocol for Hierarchical Peer-to-Peer File Sharing Systems

Qiying WEI,Tingting QIN,Satoshi FUJITA 한국정보기술융합학회 2011 JoC Vol.2 No.1

Subnanometer Vacancy Defects Introduced on Graphene by Oxygen Gas

Yamada, Yasuhiro,Murota, Kazumasa,Fujita, Ryo,Kim, Jungpil,Watanabe, Ayuko,Nakamura, Masashi,Sato, Satoshi,Hata, Kenji,Ercius, Peter,Ciston, Jim,Song, Cheng Yu,Kim, Kwanpyo,Regan, William,Gannett, Wil American Chemical Society 2014 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.136 No.6

<P>The basal plane of graphene has been known to be less reactive than the edges, but some studies observed vacancies in the basal plane after reaction with oxygen gas. Observation of these vacancies has typically been limited to nanometer-scale resolution using microscopic techniques. This work demonstrates the introduction and observation of subnanometer vacancies in the basal plane of graphene by heat treatment in a flow of oxygen gas at low temperature such as 533 K or lower. High-resolution transmission electron microscopy was used to directly observe vacancy structures, which were compared with image simulations. These proposed structures contain CO, pyran-like ether, and lactone-like groups.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2014/jacsat.2014.136.issue-6/ja4117268/production/images/medium/ja-2013-117268_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja4117268'>ACS Electronic Supporting Info</A></P>

Design of the Experimental Simulator of Magnetic Sails

Ikkoh FUNAKI,Kazuhisa FUJITA,Hiroshi YAMAKAWA,Hiroyuki OGAWA,Satoshi NONAKA 한국추진공학회 2004 한국추진공학회 학술대회논문집 Vol.2004 No.5