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Search Results: 1 - 10 of 1439 matches for " Norihiko Ishikawa "
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Single-Incision Robotic Surgery  [PDF]
Norihiko Ishikawa, Masahiko Kawaguchi, Hideki Moriyama, Go Watanabe
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.32015
Abstract: Introduction: Single Incision Laparoscopic Surgery (SILSTM) has been developed as a less invasive laparoscopic surgery. On the other hand, robotically assisted surgical technology has offered new options for minimally invasive surgery. In this study, we report a new surgical technology to perform SILS using the da Vinci S surgical system (Intuitive Surgical Inc., Sunnyvale, CA). Materials and Surgical Technique: A porcine liver with gallbladder was placed on an endoscopic surgery trainer, and a 25 mm incision was made for one robotic camera and two instruments at the umbilicus position. Both instruments were crossed while preventing them from colliding with each other, and Robot-assisted single-incision cholecyctectomy was perfumed. Discussion: This technique is expected to contribute to the development of a number of procedures in the future.
Laparoscopic Hernioplasty Using Omega-3 Coating Mesh  [PDF]
Masahiko Kawaguchi, Norihiko Ishikawa, Youji Nishida, Hideki Moriyama, Masahiro Kaneki, Go Watanabe
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.38077
Abstract: Background: Laparoscopic hernioplasty has gained popularity with significant advances in prostheses. Omega-3 coating mesh (C-Qur) is a prosthesis that can be used in the abdominal cavity, and the coating prevents adhesion of the mesh to the viscera. We planned a prospective observational study of laparoscopic hernioplasty using C-Qur. Methods: C-Qur was used in laparoscopic hernioplasty over the course of 1 year. We considered laparoscopic approaches as our primary treatment method for abdominal wall hernias. Although only a single incision was made for the majority of the laparoscopic hernioplasties, additional incisions were made when severe adhesions were encountered. For incisional or ventral hernias, a lateral lower incision was made. For inguinal hernias, an umbilical incision was made. Sex, age, diagnosis, number of incisions, additional incisions, morbidity, and follow-up period were evaluated. Results: Twenty-four patients who underwent surgery between May 2010 and April 2011 were included in this study. The median follow-up period was 14 months. The most common early complications included wound pain and edema; however, there were no persistent complications.
The da Vinci Surgical System versus the Radius Surgical System  [PDF]
Norihiko Ishikawa, Go Watanabe, Noriyuki Inaki, Hideki Moriyama, Masanari Shimada, Masahiko Kawaguchi
Surgical Science (SS) , 2012, DOI: 10.4236/ss.2012.37070
Abstract: Objective: Kanazawa University introduced the da Vinci surgical system and the Radius surgical system. In this study, we compared the advantages and disadvantages of each system. Methods: The da Vinci system is a master-slave tele-manipulation system, which provides hi-resolution 3D images. The Radius system is pair of hand-guided surgical manipulators. In this study we focus on the operability of both instruments rather than their 3D optical systems. Results: The Radius was originally developed specifically focused on ligation and suturing with suture sizes bigger than 4-0, it is more effective, less expensive compared with the da Vinci. Although the da Vinci system is bulky, it allows surgeons to perform endoscopic surgeries only if ports are properly placed to prevent each arm from colliding with the other arms. A crucial difference between the Radius and the da Vinci is not limited to anastomose small vessels but is extended to multidirectional dissection. Currently, the cost including initial investment is the biggest issue; however, the da Vinci is absolutely necessary to implement delicate cardiac surgeries endoscopically and less-invasively. Early approval of robotic surgery by the government is urgently required in Japan. Conclusions: Although both the da Vinci and the Radius have endoscopic instruments with a multi-degree of freedom, applications need to be differentiated depending on the procedures and indications. Therefore, it can be clearly said that these unique innovative systems will never compete against each other.
Laparoscopic Observations in Acquired Inguinal Hernia before and after Robotic-Assisted Laparoscopic Prostatectomy  [PDF]
Masahiko Kawaguchi, Yoshifumi Kadono, Masanari Shimada, Hideki Moriyama, Norihiko Ishikawa, Go Watanabe
Surgical Science (SS) , 2014, DOI: 10.4236/ss.2014.54030
Abstract: Background: The mechanism of the development of acquired inguinal hernia, especially indirect inguinal hernia, is not well known. Although anatomical studies have been performed to explain development of inguinal hernia, they have mainly involved autopsy or temporal findings at the time of hernioplasty. To elucidate the pattern of development of acquired inguinal hernia, we studied the occurrence of inguinal hernia after robotic-assisted laparoscopic prostatectomy (RALP). Methods: From March 2009 to November 2011, RALP for prostatic cancer was performed on 60 patients in our institute. The RALP was performed by one urologist using the da Vinci Surgical System. The postsurgical development of inguinal hernia was diagnosed based on patients’ symptoms. Seven patients were treated with laparoscopic hernioplasty, and one underwent mesh-plug repair. Using video recordings, the laparoscopic findings during RALP and laparoscopic hernioplasty were compared among all patients. Results: Seven of 59 patients (11.9%) developed an inguinal hernia. One patient had a pre-existing pantaloon inguinal hernia at the time of RALP. Eleven inguinal lesions in the seven patients who underwent laparoscopic hernioplasty were reviewed, and all were indirect inguinal hernias. Conclusion: A main factor in the development of inguinal hernia after RALP could be a combination of outer-side intact layers and inner-side hard scar of the inguinal ring, which seems like “out swing door”.
Sampling Strategies in Antimicrobial Resistance Monitoring: Evaluating How Precision and Sensitivity Vary with the Number of Animals Sampled per Farm
Takehisa Yamamoto, Yoko Hayama, Arata Hidano, Sota Kobayashi, Norihiko Muroga, Kiyoyasu Ishikawa, Aki Ogura, Toshiyuki Tsutsui
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0087147
Abstract: Because antimicrobial resistance in food-producing animals is a major public health concern, many countries have implemented antimicrobial monitoring systems at a national level. When designing a sampling scheme for antimicrobial resistance monitoring, it is necessary to consider both cost effectiveness and statistical plausibility. In this study, we examined how sampling scheme precision and sensitivity can vary with the number of animals sampled from each farm, while keeping the overall sample size constant to avoid additional sampling costs. Five sampling strategies were investigated. These employed 1, 2, 3, 4 or 6 animal samples per farm, with a total of 12 animals sampled in each strategy. A total of 1,500 Escherichia coli isolates from 300 fattening pigs on 30 farms were tested for resistance against 12 antimicrobials. The performance of each sampling strategy was evaluated by bootstrap resampling from the observational data. In the bootstrapping procedure, farms, animals, and isolates were selected randomly with replacement, and a total of 10,000 replications were conducted. For each antimicrobial, we observed that the standard deviation and 2.5–97.5 percentile interval of resistance prevalence were smallest in the sampling strategy that employed 1 animal per farm. The proportion of bootstrap samples that included at least 1 isolate with resistance was also evaluated as an indicator of the sensitivity of the sampling strategy to previously unidentified antimicrobial resistance. The proportion was greatest with 1 sample per farm and decreased with larger samples per farm. We concluded that when the total number of samples is pre-specified, the most precise and sensitive sampling strategy involves collecting 1 sample per farm.
Cloud Service Provisioning Based on Peer-to-Peer Network for Flexible Service Sharing and Discovery  [PDF]
Andrii Zhygmanovskyi, Norihiko Yoshida
Journal of Computer and Communications (JCC) , 2014, DOI: 10.4236/jcc.2014.210003

In this paper, we present an approach to establish efficient and scalable service provisioning in the cloud environment using P2P-based infrastructure for storing, sharing and discovering services. Unlike most other P2P-based approaches, it allows flexible search queries, since all of them are executed against internal database presenting at each overlay node. Various issues concerning using this approach in the cloud environment, such as load-balancing, queuing, dealing with skewed data and dynamic attributes, are addressed in the paper. The infrastructure proposed in the paper can serve as a base for creating robust, scalable and reliable cloud systems, able to fulfill client’s QoS requirements, and at the same time introduce more efficient utilization of resources to the cloud provider.

Detailed Mechanism and Engineering Applicability of Electrolytic Polymerization Aided by a Magnetic Field in Natural Rubber by Mechanical Approach for Sensing (Part 1): The Effect of Experimental Conditions on Electrolytic Polymerization  [PDF]
Kunio Shimada, Norihiko Saga
World Journal of Mechanics (WJM) , 2016, DOI: 10.4236/wjm.2016.610026
Abstract: Ordinary electrolytic polymerization has involved plastic-type polymer solutions. Rubber, especially natural rubber, is one such polymer solution. Rubber has not been focused on until recently due to the fact that electrolytic polymerization has only a very small effect on rubber. However, when we focus on the C=C bonds of natural rubber, the same electrolytic polymerization is applicable to be enlarged on the natural rubber if a magnetic field and a filler are added. With the application of a magnetic field and a magnetic responsive fluid such as magnetic compound fluid (MCF), the effect of electrolytic polymerization on NR-latex such as plastic-type polymer solutions is enhanced, and the thickness of the vulcanized MCF rubber grows in a short time. The present new method of vulcanization of MCF rubber is effective enough that it is widely used in haptic sensors in various engineering applications. In the present report, as mechanical approach for the sensing, by measuring the temperature under electrolytic polymerization, by investigating the electric and dynamic characteristics, and by observing the magnified appearance of the MCF rubber, we clarified the extrinsic effects of many experimental conditions, including magnetic field strength, applied voltage, the electrodes gap, mass concentration, and the ingredients of the MCF. This report is Part 1, to be followed by another sequential report, Part 2, in which other intrinsic effects on the characteristics are dealt with. The experimental conditions used and the results obtained in the present report provide valuable data that will be useful in the making of MCF rubber.
Detailed Mechanism and Engineering Applicability of Electrolytic Polymerization Aided by a Magnetic Field in Natural Rubber by Mechanical Approach for Sensing (Part 2): Other and Intrinsic Effects on MCF Rubber Property  [PDF]
Kunio Shimada, Norihiko Saga
World Journal of Mechanics (WJM) , 2016, DOI: 10.4236/wjm.2016.610027
Abstract: The same ordinary electrolytic polymerization of plastic-type polymer solution is applicable to natural rubber, with its C=C bonds, if a magnetic field and a filler are added. With the application of a magnetic field and the magnetic responsive fluid known as magnetic compound fluid (MCF), we have clarified the enhancement of the electrolytic polymerization of NR-latex and the growth of the thickness of vulcanized MCF rubber that results from the addition of a magnetic field. The present new method of MCF rubber vulcanization is effective for use in haptic sensors, which are used widely in various engineering applications. In the previous report, part 1 of this study, we investigated many experimental conditions under mechanical approach for sensing: magnetic field strength; applied voltage; electrodes gap; mass concentration, and the ingredients of the MCF. In the present sequential report, part 2, we investigate many other effects on electrolytic polymerization by the same mechanical approach for sensing as in part 1: the Mullins effect; the Piezo effect; vibration; kind of electrode; atmospheric gas. In particular, we clarify that the voltage generates spontaneously in the MCF rubber and that the MCF rubber becomes a Piezo element. These effects on the electrolytic polymerization as well as the effects of the experimental conditions will be useful in engineering applications. By taking the above-mentioned parameters and effects into account, MCF rubber that is electrolytically polymerized with the aid of a magnetic field, the use of MCF as a filler, and doping, can be useful in haptic sensor applications. In particular, the effectiveness of the Piezo element can be shown.
Carotenoid β-Ring Hydroxylase and Ketolase from Marine Bacteria—Promiscuous Enzymes for Synthesizing Functional Xanthophylls
Norihiko Misawa
Marine Drugs , 2011, DOI: 10.3390/md9050757
Abstract: Marine bacteria belonging to genera Paracoccus and Brevundimonas of the α -Proteobacteria class can produce C 40-type dicyclic carotenoids containing two β-end groups (β rings) that are modified with keto and hydroxyl groups. These bacteria produce astaxanthin, adonixanthin, and their derivatives, which are ketolated by carotenoid β-ring 4(4′)-ketolase (4(4′)-oxygenase; CrtW) and hydroxylated by carotenoid β-ring 3(3′)-hydroxylase (CrtZ). In addition, the genus Brevundimonas possesses a gene for carotenoid β-ring 2(2′)-hydroxylase (CrtG). This review focuses on these carotenoid β-ring-modifying enzymes that are promiscuous for carotenoid substrates, and pathway engineering for the production of xanthophylls (oxygen-containing carotenoids) in Escherichia coli, using these enzyme genes. Such pathway engineering researches are performed towards efficient production not only of commercially important xanthophylls such as astaxanthin, but also of xanthophylls minor in nature (e.g., β-ring(s)-2(2′)-hydroxylated carotenoids).
On the random variable $\N^r \ni (k_1, k_2, ..., k_r) \mapsto \gcd(n,k_1k_2... k_r) \in \N$
Norihiko Minami
Mathematics , 2009,
Abstract: We compute the "moments" and its continuous anaougue of the random variable $\N^r \ni (k_1, k_2, ..., k_r) \mapsto \gcd(n,k_1k_2... k_r) \in \N$ by a purely elementary method. This generalizes a result of Kurokawa-Ochiai, which computed its "average" using some analysis involving L-function.
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