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Laparoscopic choledochotomy on patients indicated for common bile duct exploration was carried out according to an algorithm for managing choledocholithiasis. This study describes retrospectively our method and evaluates a new cystic duct biliary decompression cannula (J-tube) as an alternative to the T-tube.Patients with confirmed choledocholithiasis (n=46) underwent laparoscopic choledochotomy. The T-tube was inserted in cases with suspected retained stones after common bile duct clearance, and the J-tube (950-mm long, 4 Fr) with a tapered and J-shaped segment at the distal end was inserted in other cases.Only 1 case was converted to open surgery (success rate, 97.8%); the J-tube was inserted in 30 patients and the T-tube in 15. The median operation time, hospital stay, and the interval until removal of the tube were significantly shorter with J-tube than with T-tube cases. Bile leakage after surgery occurred in 4 J-tube and 2 T-tube cases with one residual stone in each case.The transcystic decompression tube is easily and safely inserted with the J-kit. Among several strategies currently available for the management of choledocholithiasis, laparoscopic choledochotomy with the use of the J-tube is one of the safest and most feasible methods.

Background: Multiple colon polyps and early cancers are often detected at colonoscopy, but we could not collect all polypectomied specimens in one insertion of a colonoscope. Endoscopic mucosal resection (EMR) may often be very difficult for the collection of the size, type, form, or location of the polyps. Methods: We performed EMR to collect plural polypectomied specimens by a modified new technique using a clip connected with a string in 40 patients (25 male, 15 female) who visited Saiseikai Nakatsu Hospital and Mitsubishi Kobe Hospital for colonoscopic treatment. The method was as follows: (i) insert a colonoscope; (ii) check polyps by indigocarmine pigmentation and endoscopic ultrasonography (EUS); (iii) check the lift-up sign by submucosal injection of 2.5% hypersaline-epinephrine containing indigocarmine; (iv) make a clip connected with string (Tegusu-3 go) and insert the clip kit through the channel of the colonoscope; (v) clip the polyp; (vi) insert snare in the channel of an endoscope, passing the string through the center of the snare; (vii) snare the polyp with counter traction of string and cutting by bipolar electric power; (viii) check for bleeding. If there is bleeding from the polypectomied site, another clip is necessary; and (ix) collect polyp. If there are many polyps, flags connecting the string are required. Results and Conclusion: All polyps were treated and collected in all patients by one insertion of the colonoscope without complications. Our modified EMR method was useful in the collection of multiple polypectomied polyps.

INTRODUCTION The consumption of green tea is associated with a lower risk of several types of human carcinomas. A number of studies have focused on the possible mechanisms of cancer prevention by tea extracts, especially polyphenols such as epigallocatechin-3-gallate (EGCG). AIMS AND METHODOLOGY Green tea-derived EGCG was tested in human pancreatic carcinoma cells. The cells (PANC-1, MIA PaCa-2, and BxPC-3) were treated with different doses of EGCG (0, 25, 50, 100, and 200 micromol/L) for 48 hours in culture medium. Proliferation of pancreatic carcinoma cells was measured by means of the WST-1 colorimetric assay. For the study of cell invasion, the cells were incubated with 100 micromol/L EGCG for 2 hours. Then, the cells were added into the cell insert, coated with Matrigel basement membrane matrix. After incubation at 37 degrees C for 24 hours, the cells that had invaded through the Matrigel were counted visually under the microscope. RESULTS The growth of all three pancreatic carcinoma cells was significantly suppressed by EGCG treatment in a dose-dependent manner. EGCG treatment caused significant suppression of the invasive ability of pancreatic carcinoma cells PANC-1, MIA PaCa-2, and BxPC-3 but did not affect the cell cycle protein cyclin D1. CONCLUSION EGCG may be a potent biologic inhibitor of human pancreatic carcinomas, reducing their proliferative and invasive activities.

A classifier system for the reinforcement learning control of autonomous mobile robots is proposed. The classifier system contains action selection, rules reproduction, and credit assignment mechanisms. An important feature of the classifier system is that it operates with continuous sensor and action spaces. The system is applied to the control of mobile robots. The local controllers use independent classifiers specified at the wheel-level. The controllers work autonomously, and with respect to each other represent dynamic systems connected through the external environment. The feasibility of the proposed system is tested in an experiment with a Khepera robot. It is shown that some patterns of global behavior can emerge from locally organized classifiers.

An autonomous robot that acts in a complex environment needs to learn which action should be performed in each external state. Therefore, we propose a new control architecture for autonomous robots. The control architecture includes a learning system, which consists of globally coupled chaotic elements. A chaotic element has dynamics which are designed so that the elements can collectively execute reinforcement learning. Although each element continuously updates its internal state according to its intrinsic dynamics, this local processing collectively determines an action of the robot and allows it to interact with its environment. The result of this interaction returns to the elements as a payoff, which changes the dynamics. We carried out computational experiments for a navigation task. The results show that the chaotic elements self-organize so that an autonomous mobile robot exhibits such behaviors as goal-reaching, wall-following and collision avoidance.

We report a case of multiple liver metastases from colon cancer initially thought to be incurable and review several literature cases. The patient has survived for 3 years without tumor relapse after multimodality therapy and surgical intervention was performed.

In order to reach a better productivity in numerous fields, robots have been wildly used for automatic tasks. The main issue of a robot is his lack of adaptability, which is one of the most important ability of human beings. The best tool for adaptability is the human hand. Using pneumatic actuators to drive a robot forearm grants the possibility to move light articles with accuracy and without harming it. It is then necessary to develop accurate model of the different types of actuators. As every human muscle are simulated by those actuators, the size of these must vary and so their properties as well. These artificial muscle-type pneumatic actuators are composed of a rubber balloon, a net, a feeding channel and finally two anchors at both end of the net. Starting with the simplest linear model, we increased the complexity of the model to finally obtain a powerful control of the plastic muscle. To obtain the data we needed for the model, we used a test bench for pneumatic actuators and adjust it to fit the new size of the current actuator. The main difficulty to control the actuator is to find a way to overcome its hysteresis cycle. Then once the model is ready we need to use it to control the different part of the pneumatic forearm. The previous wrist and hand control is enhanced by feed forward control and can perform motion with a great accuracy. The hand can therefore be used without any electronic devices on it and remains lighter and safer. Previous starting dead-zone has been understood and avoided.Copyright © 2012 by ASME

Recently, research and development in robotics have focused on robots performing tasks traditionally done by people. Therefore, it is necessary for robots to have the same flexibility as people. Additionally, such robots need to incorporate high-level safety features so as not to incur injury on others. We present artificial muscle-type pneumatic actuators as the driving source of a robot hand that is both safe and flexible. Development of robot hands using pneumatic actuators has already taken place. However, when a pneumatic actuator is used, a large compressor is needed. Therefore, the driving system also needs to be large. This is a major problem. Therefore, we developed low-pressure, low-volume pneumatic actuators for driving a robot hand that works flexibly and safely among people and a five-fingered robot hand with these pneumatic actuators installed. To accurately control the five-fingered robot hand, an accurate model with a pneumatic actuator is needed. We constructed such a model by using a spring element, which expresses the generative force of pneumatic pressure, and a damper element, which expresses the hysteresis characteristics. We then made a 1-link arm that has one degree of freedom using the pneumatic actuators and constructed a 1-link armmodel. We also constructed a spring-damper element model of the pneumatic actuators and a proportional-integral-derivative (PID) controller system. The gains of the system were determined with a simulation that uses our 1-link arm model. The step response of the joint angle was examined with these determined gains.

In recently years, the production method has changed from the diversification of a sense of values from mass production to diverse-types-and-small-quantity production on the production site. Therefore, a productive system that can correspond to changes in the environment is required. In a productive system that performs handling tasks, we use a hand-eye system with a camera and a manipulator and perform hand-eye calibration from two dimension images obtained by camera to the manipulator coordinates a three dimension system of in the hand-eye system. However, the camera and the manipulator positions in the previous system changed, and great error from the position, which performed the calibration, was caused even when the error was minute. Therefore, in this hand-eye system, changing this production system is difficult or re-calibration is needed. The projection matrix must be calculated so that the image coordinates obtained with the camera and the manipulator coordinates of three dimensions correspond again in the re-calibration. However, calculating the projection matrix requires great care. We propose a technique that simply calculates the manipulator coordinates of three dimensions from image coordinates without calculating the projection matrix again by correcting the image coordinates. Our experiment results show that the image coordinates can be corrected without calculating the projection matrix again using a landmark. In addition, a three-dimensional position was corrected simply, and we were able to handle the object.

Recently, various prosthetic arms have been developed, but few are both attractive and functional. Considering human coexistence, prosthetic arms must be both safe and flexible. In this research, we developed a novel prosthetic arm with a five-fingered prosthetic hand using our original pneumatic actuators and a slender tendon-driven wrist using a wire drive and two small motors. Because the prosthetic hand's driving source is comprised of small pneumatic actuators, the prosthetic hand is safe when it makes contact with people; it can also operate flexibly. In addition, the arm has a tendon-driven wrist to expand its motion space and to perform many operations. First, we explain the pneumatic hand's drive mechanism and its tendon-driven wrist. Next, we identify the characteristics of the hand and the wrist and construct a control system for this arm and verify its control performance.

We present an artificial muscle-type pneumatic actuator as the driving source of a robot hand that is both safe and flexible. Some development of robot hands using pneumatic actuators has already taken place. However, in using a pneumatic actuator, a big compressor is needed. So the driving system also needs to be big, and enlargement of the driving system is a major problem.

To cope with the flexibility for diversifications of products and shortened life cycles of goods and the adaptability to occurrence of unexpected events like machine troubles and task changes, BMS (Biological-Oriented Manufacturing Systems) is recently proposed as a new concept beyond existing CIM. In this study, a manufacturing ribosome model is developed as the first step to realize the BMS concept. The manufacturing ribosome is a basic structure element in the BMS, and is provided with at least three functions, transformation, transportation and verification. This paper describes a developed prototype of manufacturing ribosome and discusses it in terms of flexibility and autonomy. Finally, a realization of the transformation included in manufacturing ribosome and case study are carried out.

複雑に入り組んだ陸中海岸の入江では、回遊してくるイルカの群れを追い込んで文字通り一網打尽に捕獲する「イルカ追い込み漁」を、大正時代まで行っていたところが二ヵ所知られている。そのうちの岩手県下閉伊郡山田町大浦については、本紀要の前号において同タイトルの(上)として報告した。本稿はそれに続いて、もう一ヶ所のイルカ追い込み漁実施地区であった岩手県大船渡市赤崎の事例を報告する。赤崎におけるイルカ追い込み漁の開始時期は明確ではないが、漁の瀬主であった志田家に残る収益配分などを記載した勘定帳には享和二年(一八〇二)のものがあり、少なくともそれ以前から追い込み漁が行われていたことは確実である。本稿では、この志田家文書を基本史料とし、現地における聞き取り調査を加えて追い込み漁の実態と、それが村落生活と如何なる関係をもって実施されてきたかを考察する。なお、大船渡湾はイワシ漁に好適であっただけでなく、海草や貝類なども豊富であったため海面使用をめぐる争いが生じ、赤崎村は対岸の大船渡村との間で、いわゆる海論を繰り返してきた。その初めは元禄時代にさかのぼり、明治のいわゆる旧漁業法施行前まで三十回以上に及ぶ。注目すべきは、そのなかでイルカ漁は一貫して赤崎に独占権が認められていたと考えられるが、これは湾内に入ってくるイルカの回遊コースとも深い関連がある。つまり赤崎側は水深が深く、イルカの群れは湾の最奥に近い野島という小島の周りを三回まわって再び出て行くといわれているので、その間に赤崎側で網を張りかける時間があるということになる。なお、イルカは仲間の霊を弔うためにやってくるといわれているが、これは「海豚参詣」といわれる民俗に属し、類例が少ない東北地方太平洋側における貴重な事例である。さらに、追い込み漁の実施にあたっては、湾内で操業中のイワシ手繰り網(アラデ網)の仲間が重要な役割を果たしていたため、他地区で一般的な第一発見者に対する報償はなく、最初に網を張った「一番張り」に対して、水揚高の十五分一が与えられるという規約があった。また勘定帳には漁ごとに酒代が計上されており、さらに配分率に若干の差はあるものの、全戸に当り金が配られたこともわかる。イルカ漁が、単純な捕獲作業ではなく、集落運営全体に直結した特殊な意味をもっていたことを、この赤崎の事例でも確認できる。なお、赤崎より南の宮城県気仙沼市唐桑においては、江戸時代中ごろに積極的にイルカ漁を実施していた記録があるので、あわせて紹介し簡単な考察を加えることにする。唐桑のイルカ漁の始まりは紀州から北上してきたカツオ漁師ないし鰹節製造者との関連が想像されるが、この点は前号の山田湾大浦の事例と対照させて考えなければならない。

日本列島の太平洋側東北部に位置する陸中海岸には、リアス式の海岸線が織り成す多くの入り江がある。なかでも岩手県下閉伊郡の山田湾には、暖流に乗って回遊するイルカがしばしば「浦入り」をしてきた。湾に面した大浦集落では、これを網で囲って海岸にまで追い込んで捕獲する、イルカ追い込み漁が近世の早い時期から行なわれており、この種の漁法としては日本の最北端での実施例に位置づけられる。村内外の出資者が金本、村内の有力者が瀬主(網元)となり、集落全戸が参加して行なう大規模な漁であり、時には一度に数千頭の漁獲があった。盛岡藩には、年間五貫文の礼銭を納入して漁の権利を確保したが、藩も新規参入者を認めず村方を支持して漁を継続させた。漁の収益は全戸に配布され、公共の用途にも使用された。明治以降、岩手県の水産行政ではイルカ漁は坪外に置かれたため、漁は慣例に従って続けられていたが、いわゆる旧漁業法が施行されてイルカ漁の位置づけも明確になり、正規の漁業権が確立した。本稿では、この過程を史料に基づいて跡づけるとともに、村落をあげての集団漁労活動の意義と、漁民のイルカ観を考える。なお、大浦におけるイルカ漁は、大正期に入ってからは数回の捕獲記録を残すのみとなり、昭和以降は全く行なわれなくなった。