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進化ロボティクスの研究においては, シミュレーション上で進化させた個体は実環境で適切に機能することが困難であるという問題がある。そこで本研究では, 個体発生過程の概念を取り入れることにより, 環境とロボットとの相互作用の調整方法やネットワークの構造を進化の対象とする, 自律移動ロボットコントローラの進化的構築手法を提案し, その妥当性を定量的に検証する。

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In this paper, a novel synthesis method of disturbance observer which can asymptotically estimate a biased sinusoidal disturbance using the conventional disturbance observer is studied. The basic idea is to synthesize the disturbance observer gain matrix based on the following two considerations: 1) a zero located at the origin can be assigned to the closed-loop transfer function G_dd(s) from the disturbance to the disturbance estimation error, 2) all poles of G_dd(s) can be obtained in the complex left half-plane. The zero assignment of G_dd(s) can be accomplished using only one element of the gain matrix, and all poles of G_dd(s) can be assigned using the remaining elements of the gain matrix. The usefulness of the proposed method is verified by the angle control of a direct current(DC) motor system with the estimation performance of disturbances.

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In this letter, a synthesis method for semi-strongly stabilizable compensators based on disturbance observers (DOB) for second-order lag systems is proposed. The basic idea is to synthesize the gain of the DOB such that some of the compensator poles are fixed on the imaginary axis, while another can be assigned to the open left half-plane. Usefulness of the proposed method is illustrated by an experimental example showing semi-strong stabilization and disturbance attenuation performance.

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Suppression of the particle generation from the emitter of the corona discharge air ionizer is one of the most important issues to maintain the clean room at low contamination level. The particle generation rate increases with increasing the ion creation rate, because the particles are generated by spattering effect of the generated ions. In order to find out the optimum operating condition by controlling the ion transportation efficiency, that is defined as the ratio of the ion number arrived at the working aria to the of ion number created at the emitter of the air ionizer, we investigated the relationship between the ion transportation efficiency and the frequency of the power supply as an operating condition of the air ionizer. The low frequency operation was suitable to suppress particle generation without reducing the static neutralization performance, because the ion transportation efficiency increased with decreasing the operating frequency.

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The purpose of this study was to consider the discrepancy between the trunk-based and the pelvis-based joint angles, and the difference between the MTC lengths estimated on the basis of the two types of joint angles during dynamic movement. Ten male athletes performed CMJ. Joint kinematics and the MTC length of long head of biceps femoris were compared between the trunk-based angle and the pelvis-based angle. In the CMJ, the angular displacements of the trunk-based were significantly higher than that of pelvis-based joints. There were no significant correlations between the two types of joint angles except at initial position. As for long head of biceps femoris, in contrast with the trunk-based- joint angle derived MTC length, which shows stretching in the descending phase and shortening in the ascending phase, the pelvis-based joint angle derived MTC length shows little changes. These results suggest that the trunk-based and pelvis-based joint angles have similar patterns of fluctuation; however, the angular displacement of each type is not equivalent. These results also suggest that we may misinterpret the type of muscle contraction because the definitions of joint angle are different even for the same muscle type.

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    We encountered a case of rheumatoid arthritis with

destruction due to a communication between the joint and trochanteric bursa, even if this case preserved low disease activity. A 43-year-old woman with rheumatoid arthritis had a mass in the right buttock. Although she had no pain initially, she noticed a gradually growing mass, and developed pain and instability while walking within 3 years. Magnetic resonance imaging showed trochanteric bursitis in the buttock. The bursitis persisted despite aspiration for a few times, and destruction was subsequently detected. After total arthroplasty, she felt no pain in the right while walking.　
    Intraoperative findings of excessive synovial fluid that was discharged immediately after incision of the joint capsule demonstrated a communication between the trochanteric bursa and joint. Although some reports have described iliopectineal bursitis associated with rapid joint destruction, to our knowledge, no report has described a similar association between trochanteric bursitis and joint destruction. We speculated that the communication caused giant trochanteric bursitis, and it remained a few years because of a “valve-like mechanism” similar to that in a popliteal cyst.

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【Purpose】Femoroacetabular impingement（FAI）has been increasingly defined as a source of pain and become the most frequent indication for arthroscopy. However, conservative treatment for FAI has still remained controversial. The purpose of this study was to examine the efficacy of the additional trunk stabilization exercise for treating conservatively the patients with FAI.【Methods】Fifteen FAI female patients who met the inclusion criteria were enrolled in this study. There were cam type of FAI in 13 cases, and combined in 2 cases. Patients were divided into two groups of Trunk stabilization exercise group（8 cases）and Control group（7 cases）, Trunk exercise group received the additional trunk stabilization exercise program（Plank and Bird-Dog）to general exercise program（including gluteal muscle）, while Control group received only general exercise for four weeks. Outcomes were based on these parameters of ①physical characteristics, ②Tegner Activity Score, ③Numeric Rating Scale：NRS, ④ function score（Modified Harris Score：MHHS・Vail Score）, ⑤range of joint, ⑥muscle strength of , ⑦side bridge, ⑧femoral neck anteversion were measured before and at 4 weeks after intervention. Efficacy of intervention was analyzed using two-way ANOVA.【Results】There were no significant differences of all parameters between both groups before intervention. We recognized the interaction effect on Vail Score（p＜0.05）. MHHS and NRS improved more in Trunk exercise group than Control group（p＜0.05）. We also found significant main effect on muscle strength after the intervention for both groups. We could not find significant effect on range of motion of joint.【Conclusion】An additional trunk stabilization exercise could be effective to improve function for treating conservatively the female patients with FAI.

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Purpose Exercise of patients was carried out to maintain and improve their body functions. The load on the joint during exercise was analyzed using the integrated EMG and force measurement of agonist and antagonist muscles. Method Experiment 1: The relationship between the integrated EMG and the muscle force of abduction was examined to identify their linearity up to 100% MVC using a Cybex 6000. Twelve lower extremities of six healthy males were used. Experiment 2: The load on the joint was estimated through this experiment, using twenty lower extremities of ten healthy males. Exercises such as straight leg raising (SLR), abduction, and knee extension were performed. The integrated EMG at 100% MVC and the muscle force of agonist and antagonist were measured. Then the integrated EMGs of agonist and antagonist were measured to determine the muscle force in proportion to the force at 100% MVC. Mathematical models were used to analyze the load on the joint in each exercise. Results Experiment 1: The integrated EMG and the muscle force of the abduction showed a strong linearity up to 100% MVC. Experiment 2: In SLR, the resultant force on the joint was 908 N and 1.4 times body weight at 10 degrees flexion. It was 765 N and 1.2 times body weight at 20 degrees, and 657 N and equal to body weight at 30 degrees. In abduction in the lateral position, it was 1.8 times body weight at 10 degrees abduction, and it decreased with increasing abduction. In knee extension with sitting, it was 127 N and 0.2 times body weight at a 60-degree knee flexion angle, and it increased gradually with knee extension. Conclusion The analyzed values showed good agreement with those from sensorized prostheses. The proposed method in this study was considered appropriate for evaluating the load on the joint during exercise. In SLR, the load was 1.4 times body weight, which was unexpected. Our approach will be applicable to other exercises in a rehabilitation protocol.

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Mathematical model analysis was carried out on the gait of patients with diseases in order to clarify the patients' gait characteristics which were not obtainable by usual techniques. Motion in the sagittal plane was noted, and a two-dimensional mathematical model developed by Yamazaki was used. For the anthropometrical measurements, 'contour maps' were used bucause patients' body proportions were different from the norm. Displacement was measured by PSD camera simultaneous to floor reaction force measurements and these were transmitted to mini-computer by on-line real-time processing. Subjects were 17 patients with osteoarthritis (11 for total replacement, 1 for hemi-prosthetic reconstruction, 3 for osteotomy, and 2 for arthrodesis of the ); 4 normal subjects were measured for control. Joint moments, muscle forces, and joint reaction forces were assumed by mathematical model analysis. In order to investigate the validity of measurements and analysis, joint reaction forces of normal subjects were compared with results of other researchers and good agreement was obtained. For the patients with total replacement, the maximum value of joint reaction force was almost the same as that of the normal subjects, but the duration for which the large force was transmitted was longer than for normal subjects. Also, it became evident that the large force was transmitted to the knee joint in the push-off phase. These were common characteristics of patients for hemi-prosthetic reconstruction and osteotomy, and it can be said that they provide compensation for the instability of and knee joints. In patients with arthrodesis of the , the maximum values of reaction force with contralateral joint and bilateral knee joints revealed about twice the normal value. Thus, it is evident that it is necessary to discuss the durability of these joints when the procedure for arthrodesis of the is applied.

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Low-level laser irradiation was given to the area surrounding the joint in 113 cases with congenital dislocation of the (27 with luxation, 86 with subluxation), in order to eliminate soft tissue strain around the joint during reduction of the dislocation. The patients were all infants below 6 months of age at presentation. Treatment of congenital dislocation of the consisted of functional treatment using a Pavlik harness in 107 cases, re-wearing of the harness after horizontal traction in 2 cases, and abduction traction in 4 cases.
Low-level laser therapy was effective for eliminating soft tissue strain around the joint, proving to be useful as a physical therapy procedure prior to the use of the harness. Following laser irradiation, the femoral head could be readily elevated, even during horizontal traction.
Thanks to the use of low-level laser, which was introduced in 1993, reduction could be conservatively attained in all the patients and no avascular necrosis of the femoral head occurred in any of the cases.
It is important to make the best attempt to achieve reduction by conservative methods in the treatment of congenital dislocation of the . As low-level laser irradiation is nonstimulating, noninvasive, and easy to deliver, and has no adverse effects, it is useful as physical therapy for eliminating soft tissue strain around the joint before and after reduction of congenital dislocation of the .

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The early results of minimal incision surgery (MIS) were compared with those of the standard procedure using the Revelation System (DJO Surgical). From June 2004 to December 2005, 40 primary total arthroplasties (38 patients) were performed. In the 40 hips, 22 hips underwent MIS (initial skin incision of less than 10 cm) and 18 hips underwent the standard procedure. At the final investigation, 21 hips from the MIS group and 17 hips from the standard group were followed up. The average follow-up was 41 months (3452 months). Two surgeons (YT, NW) performed all surgeries in this series. All operations were started with the MIS procedure (initial skin incision of less than 10 cm), but when the surgeons considered it was impossible or not suitable to continue the MIS approach during the operation, an additional skin incision and soft tissue release were applied. Each surgeon decided whether MIS was appropriate for each patient or not. The antero-lateral approach (modified Dall) was used for all surgeries. The same rehabilitation program was used for both groups postoperatively. The applicability of MIS was significantly less in male patients (males: 2/8, females: 20/32). There was a correlation between patients height and the length of skin incision (p < 0.05). No significant differences between the two groups were found in CRP, CPK and D-dimer (CRP: 14.2/12.5 mg/dl, CPK: 396.7/368.1 mg/dl, D-dimer: 14.2/5.2 mg/dl). Both intraoperative blood loss and operation time were less in the MIS group (blood loss 529.4 ml vs. 766.7 ml, operation time 101 min vs. 115 min). The postoperative days until the patient was able to do active straight leg raising (SLR) were 17.4 in the MIS group and 22.8 in the standard group, and number of days in hospital was 22.6 versus 29.2, respectively. However, no significant differences with duration of hospitalization were found statistically. On radiographic findings, the lateral inclination of the acetabular cup was 42.7 in the MIS group versus 40.9 in the standard group, showing no significant difference (p = 0.459). The score according to the Japanese Orthopedics Association (JOA) was not significantly different between the two groups at the final follow-up (88.1 in MIS group, 85.9 in standard group). At 3, 6, 12, 18, 24 and 30 months after operation, JOA scores were not significantly different between the two groups. There were no revision cases in this study until the final follow-up. In the present study, intra-operative hemorrhaging and operation time were significantly less in the MIS group. However, for the other parameters, no significant differences were found in the laboratory data, radiographic findings, hospitalization, or JOA scores.

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In the past several years, Hot Isostatic Processing () has grown as a production tool in a wide range of industries.
is one of the most important process for powder compaction, defect healing, diffusion bonding, etc.
The following description explains the equipment, emphasizing the major parts. In addition to this, some process applications of metals and ceramics powder consolidation are outlined.

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A wear characterization of commercial joint prostheses was conducted by means of a wear simulator. Bovine serum solution was used as a lubricant, and tests were conducted up to 5×10⁶ cycles. At first, the effect of testing conditions on wear of the joint prostheses was examined in order to determine the optimum conditions for simulator testing. As a result, it could be clarified that the serum concentration in the lubricating fluid and the intervals of time between lubricant replacements highly affect the wear of ultra-high molecular weight polyethylene (UHMWPE). Formation of a protein film on the acetabular cup and increasing wear at initial stage after lubricant replacement are likely the reasons for this phenomenon. By using standardized conditions, long-term simulator tests are conducted against six types of commercial joint prostheses. The results clearly reveal the difference in wear resistance of each combination. The present data can be considered to be reference data for developing new types of joint prosthesis.

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Congenital dislocation of the is a problematic condition to treat, and if not treated, or treated incorrectly, mobility for the affected infant can be severely compromised. This study involved 66 patients with congenital dislocation of the (infants within 6 months of birth) treated at our center (mean age upon first examination: 3 months), including 30 patients who underwent low reactive-level laser therapy (LLLT) and 36 who did not. The 30 patients who received LLLT did so in combination treatment with a Pavlik harness or traction therapy for a mean period of 3 months (3 sessions of LLLT irradiation per week). The time course of changes in the acetabular angle, the central edge (CE) angle and the ossific nucleus of the femoral head were compared between patients in the group that received LLLT and those that did not. LLLT combined with conventional treatment for congenital dislocation of the resulted in less tension in the soft tissue around the joint, more natural reduction of dislocations with the Pavlik harness or traction, and a reduction in the size of interpositions within the joint as well as improved centripetalism, thus contributing to prevention of the onset of femoral head necrosis. In addition, LLLT favorably affected the formation of the acetabulum as well as growth of the femoral head. This is probably because the improved centripetalism combined with LLLT bioactivation of osteoblasts facilitated acetabular repair, leading to the prevention of coxa magna. When administered to patients with congenital dislocation of the , LLLT was pain-free, stress-free and easy to apply. No adverse reactions were recorded in any of the 30 patients in the present study. If LLLT is applied in combination with other means of therapy in the early stages of treatment of congenital dislocation of the , it is likely to enable patients to avoid additional corrective surgery (open reduction of dislocations, pelvic osteotomy, femoral neck osteotomy, and so on) as well as prevent the onset of pursuant diseases and conditions, such as femoral head necrosis. LLLT is thus a promising new means of treatment for congenital dislocation of the .

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Background:Although elevated levels of oxidized low-density lipoprotein (LDL) could play a critical role in vulnerable plaque, there are no studies that have compared coronary high-intensity plaque (

) and circulating malondialdehyde-modified (MDA)-LDL levels for the prediction of cardiac events.

Methods and Results:A total of 139 patients with coronary artery stenosis (>70%) were examined with non-contrast T1-weighted magnetic resonance imaging (MRI) (

: n=64, non-: n=75). Scheduled percutaneous coronary intervention (PCI) for culprit lesions was performed within 48 h after MRI. was defined as a signal intensity of coronary plaque to cardiac muscle ratio (PMR) ≥1.4. We evaluated the subsequent major adverse cardiac events (MACE) during the follow-up period (5.6±1.3 years). MDA-LDL levels were independently associated with the presence of (P<0.0001). The incidence of MACE was 15%, and it was significantly higher in patients with (27%) than in those without (5%; P=0.011). Cox proportional hazard analysis showed MDA-LDL levels (P=0.007) and PMR (P=0.016) were significantly associated with MACE. For MACE prediction, C-statistic values for MDA-LDL, PMR, and PMR+MDA-LDL were 0.724, 0.791, and 0.800, respectively. Compared with MDA-LDL alone, the addition of PMR to MDA-LDL increased net reclassification improvement by 0.78 (P=0.012).

Conclusions:MDA-LDL levels might be associated with the presence of

in patients with coronary artery disease. Furthermore, adding PMR to MDA-LDL levels markedly improved prediction of subsequent MACE after PCI.

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Patients with rheunatoid arthritis who have bilateral joints ankylosis can not stand and walk unless at least one joint obtains its mobility. For the purpose of mobilization of the ankylosed joint the mold arthroplasty, prosthetic arthroplasty, or Whitmanis or Colonna's reconstruction has been performed.
Weight-bearing on the operated fragile , however, frequently results in postoperative fracture or severe pain which necessitates to make re-operation. Accordingly, it seems that mobilization by means of resection of the head or neck of the femur in bilateral joints ankylosis with fragile bone particularly as in rheumatoid patients is the first choice of the surgery.
We had two cases involved in bilateral -joints ankylosis due to rheumatoid arthritis. One was 29 years old female, the other was 28 years old female. These two patients have had to be recumbent on the bed for around 10 years.
Their bones were markedly fragile in X-ray findings with former surgery of the other joints.
The 29 years old patient had resection of the head and neck of the right femur. One and half year after the surgery, she could walk several handred meters with a Thomas' splint adapted on the operated leg using forearm crutches.
The other case had resection of the neck of the right femur, eight months thereafter, she had osteotmy in supracondylar region of the left femur to get functional position of the left knee ankylosed on flexion. In this case also, much better functional capacities in the daily life activity were obtained.
At present time, one year after the mobilization of the , she has been taken bed exercise, and it is expected that she will get ability of standing and walking in near future.

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