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As fully automated robotic systems are difficult to realize from the viewpoint of cost efficiency and currently available technologies, human-robot cooperative systems have been widely studied. This paper presents a model reference control approach for a human-operated robotic system. This approach provides functions to incorporate commands given by a human operator and compensate for mistakes committed by the operator in real time, and is applied to a manipulator control whose objective is to transport an object on a table at the end-effector. The proposed method provides the following three functions: collision avoidance, tumble avoidance of the transported object, and singular point avoidance, even when the human operator makes mistakes during operation. There are many applications of this type of robotic manipulator in industrial and household tasks. The effectiveness of the proposed method is confirmed by the experiments in which several unskilled operators operate the manipulator to transport an object in a narrow space.

This note presents a controller design for overhead cranes that provides robustness with respect to changes in rope length and transported mass. Elsewhere it has been recommended that the rope angular velocity feedback gain should be assigned to zero in linear quadratic (LQ) controller design. In this study, the gain is assigned to zero from another viewpoint, and hence the proposed controller is a partial state feedback controller. The proposed method provides a robust controller design without iterative computations. Simulation results demonstrate the effectiveness of the proposed design.

The feasibility of applying single‐chamber solid oxide fuel cells (SC‐SOFCs) to power generators for exhaust energy recovery was investigated using both model and actual exhaust gases. In the experiments with model exhaust gases, a single cell, Ni‐Ce0.8Sm0.2O1.9/YSZ/La0.8Sr0.2MnO3, was operated in a mixture of gases containing ppm levels of CH4, C2H6, C3H8, C4H10and O2. The cell performance was considerably affected by the molar ratio of total hydrocarbons to O2, the operating temperature and the gas flow rate. The optimal operating conditions of the SC‐SOFC were found to be similar to those found in actual exhaust from gasoline engines. Thermal and mechanical loading performance tests demonstrated high tolerance towards thermal cycling and breakage of the electrolyte. Performance tests with and without a gas separator suggested that there is no requirement for a gas separator in an actual exhaust. In the experiments with actual exhaust gases, a 12‐cell stack was installed to a 250‐cm3engine. The open circuit voltages (OCVs) were between 5 and 8 V and independent of the number of revolutions, but were lower than the values expected from the model exhaust results. This was considered to be due to the deviation of the actual exhaust gases from the model gases. Nevertheless, the stack performance was reproducible and stable in the range from 1,500 to 5,500 rpm. The resultant peak power reached above 1 W at 4,500 rpm.

A 60-year-old man presented with syncope and transient left-sided motor weakness. Cerebral angiography revealed multiple severe atherosclerotic stenoses of bilateral internal carotid arteries, bilateral intracranial vertebral artery (VA), and left VA origin. A SPECT study showed poor cerebral perfusion and vascular reserve in the right cerebral hemisphere and the posterior circulation. We performed angioplasty and stentings for the VA stenoses first by using balloon-expandable stents.The patient had shown no syncope attack ever since, which might be due to an increased vascular reserve in the posterior circulation. The following bilateral carotid angioplasty and stentings could be performed safely. Angioplasty and stenting is feasible, and can improve cerebral perfusion even in a patient with multiple severe atherosclerotic stenoses by pre-operative appropriate haemodynamic assessment.

Two new icetexane diterpenes, cyclocoulterone (1) and komaroviquinone (2), and a novel 20-norabietane diterpene, dracocephalone A (3), were isolated from Dracocephalum komarovi. Their structures were elucidated by extensive analyses of spectral data. Komaroviquinone (2) showed strong trypanocidal activity against epmastigotes of Trypanosoma cruzi, the causative agent of American trypanosomiasis, with a minimum lethal concentration of 0.4 μM.

Four monoterpene hydroperoxides were isolated from aerial parts of Chenopodium ambrosioides along with ascaridole (1), the anthelmintic principle of this plant, as anti-trypanosomal compounds. The structures of these monoterpenes were determined to be (−)-(2S,4S)- and (−)-(2R,4S)-p-mentha-1(7),8-dien-2-hydroperoxide (2a and 3a) and (−)-(1R,4S)- and (−)-(1S,4S)-p-mentha-2,8-dien-1-hydroperoxide (4a and 5a) on the basis of spectroscopic methods and chemical correlations. In vitro trypanocidal activities of ascaridole (1) and these hydroperoxides (2a−5a) against epimastigotes of Trypanosoma cruzi were 23, 1.2, 1.6, 3.1, and 0.8 μΜ, respectively. Fresh leaves of C. ambrosioides also contained isomeric hydroperoxides 6a and 7a, and the content ratio of 2a−7a suggested that these hydroperoxides were formed through the singlet-oxygen oxidation of limonene.

Abstract: Our aim was to investigate the usefulness of helical CT during selective angiography (CT arteriography) in pretreatment assessment of unruptured intracranial aneurysms. We studied 47 unruptured aneurysms in 34 prospectively recruited patients for whom endovascular embolisation was initially considered. As pretreatment assessment, we performed rotational digital subtraction angiography (DSA) followed by CT arteriography. The findings on axial source images (axial images) and reconstructed three-dimensional CT angiography (3D-CTA) of CT arteriography were compared to those of rotational DSA, with particular attention to the neck of the aneurysm and arterial branches adjacent to it. Information provided by CT arteriography was more useful than that of rotational DSA as regards the neck in 25 (53 %) of 47 cases and as regards branches in 18 (49 %) of 37 aneurysms. On axial images, small arteries such as the anterior choroidal artery were seen in some cases. CT arteriography can provide valuable additional information about unruptured aneurysms, which cannot be obtained by rotational DSA alone. This technique is useful for obtaining anatomical information about aneurysm anatomy and for deciding the therapeutic strategy.

The aim of this study was to investigate the advantages and disadvantages of a two-stage treatment for ruptured cerebral aneurysms; partial embolization in acute stage followed by clipping in chronic stage of subarachnoid hemorrhage.Between April 1997 and August 1999, twenty ruptured cerebral aneurysms were initially treated endovasculary using Guglielmi detachable coils in our institution. Among them, complete embolization could not be achieved in 6 lesions. For these lesions, subsequent clipping was added. The radiological and operative findings, and outcomes of these cases were retrospectively reviewed.In 1 case, rerupture occurred during the endovascular procedure. Rerupture was not observed in any cases in the postembolization period. In 2 cases, complications related to the clipping but not the endovascular procedure occurred. These complications included impaired visual acuity for unverified reasons, and memory disturbance due to sacrifice of a perforator arising from the anterior communicating artery. In 3 cases, coil extraction was needed during the clipping, because the loops of the coil extended into the residual neck. Complications related to coil extraction were not observed in these 3 cases.Acute partial embolization of ruptured aneurysm appears to be effective for the prevention of subsequent rerupture during the subacute period, in which treatment for vasospasm should be performed, and the clipping procedure. However, in the case of relatively large aneurysms, small arteries or other normal structures behind the aneurysm cannot be observed directly during surgery, because of the immovability of the embolized aneurysm. Further, complete clip closure is impossible when loops of coil herniate into the neck. In such situations, coil extraction with or without resection of the aneurysm might be necessary, and care must be taken not to damage parent artery and surrounding vessels.

The purposes of this study are, firstly, to define the relationship between volume embolization ratio (VER) and degree of angiographical occlusion in endovascular treatment with Guglielmi detachable coils, and secondly, to examine influences of neck and dome sizes of aneurysms on the VER and the angiographical treatment result, and thirdly, to determine the relationship between the VER and the recanalization of coiled aneurysms.Fifty-two aneurysms in 46 patients were examined. VER ranged 8.1–31.9% (mean 18.5%). The mean VERs of each categories based on angiographical treatment results were 23.1% in complete occlusion, 16.1% in neck remnant and 12.2% in incomplete occlusion, respectively. The VER correlated significantly with both neck and dome size, while the angiographical treatment result was only affected by neck size. Five aneurysms showed aneurysmal recanalization among followed-up 41 aneurysms. All recanalized aneurysms were large, and their VERs were in range of 10.4–17.6%.Measurement of VER is useful to estimate the degree of occlusion objectively and to predict the aneurysmal recanalization. A small aneurysms with a small neck is relatively easy to achieve high VER and angiographical complete occlusion, with the consequence of less recanalization. On the other hand, a large aneurysm is liable to recanalize due to low VER, even if there was little filling of contrast medium in the aneurysmal cavity.

Sixteen ruptured aneurysms in 16 patients considered endovascular embolizations were examined. The findings of axial source images (axial images) and reconstructed three-dimensional CT angiography (3D-CTA) of helical CT were compared to those of rotational digital subtraction angiography (DSA). The aneurysmal neck and arterial branches adjacent to the neck were closely investigated.In seven out of 16 cases (43.8%), information provided by axial images and/or 3D-CTA was more useful than that of rotational DSA in evaluating the aneurysmal neck and arterial branches. Helical CT can provide valuable information on ruptured aneurysms that cannot be obtained by rotational DSA in some patients.This technique is useful to obtain anatomical information about aneurysms and to select the best therapeutic method.

Summary Sensory neurons and associated glial cells are known to express the cell-cell adhesion molecule E-cadherin. The cellular and subcellular localization of this molecule in the dorsal root ganglion, dorsal root, and spinal cord of postnatal mice was studied by the pre-embedding immunoelectron microscopic labelling technique. In the dorsal root and the superficial layer of the dorsal horn, a subset of fasciculating unmyelinated axons expressed E-cadherin at their axon-axon contacts at all ages studied, and these axons were clustered together and segregated from E-cadherin-negative axons. In contrast, pre-myelinating large-diameter axons in P2 mice as well as myelinated axons in mice from P14 to adulthood were E-cadherin-negative. Glial cells also expressed E-cadherin: In the dorsal root ganglia, all of the satellite cells expressed E-cadherin at contact sites with neurons, other satellite cells, and basal lamina, at all ages studied. In dorsal roots from P14 to adulthood, myelin-forming Schwann cells expressed E-cadherin at the outer mesaxons and the contact sites with basal lamina. Non-myelin-forming Schwann cells occasionally stained for this molecule at contact sites with the plasma membrane of E-cadherin-positive axons and at other sites. These results strongly suggest that E-cadherin plays an important role in the selective fasciculation of a particular subset of unmyelinated sensory fibres, and also in glial cell contacts.

Chemical ablation of the gallbladder with absolute ethanol and polidocanol 3% was attempted in 23 and 10 pigs, respectively, after open transhepatic cholecystostomy. Absolute ethanol caused complete necrosis of the gallbladder epithelium in 10 pigs and partial necrosis with focally present gallbladder epithelium in 9. An intact epithelium was observed in 4 pigs but it was not possible to determine whether this epithelium was the original one, not affected by the ethanol, or regenerated after previous damage. Gallbladders with hemorrhage and hydrops were frequently encountered. Gallbladders treated with polidocanol all had an intact epithelium.

This paper describes the roles of assembly process planning and operation planning. There often occurs the change of facilities because of faults and error in the actual factory floor, that required the modification of operation planning. In the operation planning, the facility data and the function data are required together with the product data in order to determine the movements of facilities to output the IR data etc.. Decisions made by the factory floor level computers/controllers are focused especially which are essential to realize the next generation autonomous distributed assembly systems. A typical example is developed to decide hand positioning of assembly robot hand to grasp the part are determined with use of both product and robot/hand data.

Forty-nine patients with primary lung cancer were treated with bronchial artery infusion of cisplatin and intravenous injection of an antidote, sodium thiosulfate. More than 50% reduction of tumor size (PR) was observed in 8 of 9 small cell carcinomas (SCLC) and in 16 of 40 non-small cell carcinomas (NSCLC). In NSCLC patients PR was obtained in 71% (12/17) after repeated infusions (200 mg cisplatin) and in 17% (4/23) after a single infusion (150 mg cisplatin). There was a significant linear relationship between cisplatin dose and tumor reduction in this group. No severe adverse effects were encountered.

Chemical ablation of the gallbladder with absolute ethanol and polidocanol 3 was attempted in 23 and 10 pigs, respectively, after open transhepatic cholecystostomy. Absolute ethanol caused complete necrosis of the gallbladder epithelium in 10 pigs and partial necrosis with focally present gallbladder epithelium in 9. An intact epithelium was observed in 4 pigs but it was not possible to determine whether this epithelium was the original one, not affected by the ethanol, or regenerated after previous damage. Gallbladders with hemorrhage and hydrops were frequently encountered. Gallbladders treated with polidocanol all had an intact epithelium.

A finite difference scheme for the unsteady Euler equations using an adaptive mesh refinement (AMR) algorithm was applied to the time-dependent flowfield of shock diffraction problems. The effectiveness of the AMR algorithm was evaluated against a uniform mesh algorithm. Computational results showed that to obtain solutions with equivalent resolution, the AMR algorithm requires much less processing time, when compared with a uniform mesh algorithm.

A 60-year-old man presented with syncope and transient left-sided motor weakness. Cerebral angiography revealed multiple severe atherosclerotic stenoses of bilateral internal carotid arteries, bilateral intracranial vertebral artery (VA), and left VA origin. A SPECT study showed poor cerebral perfusion and vascular reserve in the right cerebral hemisphere and the posterior circulation. We performed angioplasty and stentings for the VA stenoses first by using balloon-expandable stents.The patient had shown no syncope attack ever since, which might be due to an increased vascular reserve in the posterior circulation. The following bilateral carotid angioplasty and stentings could be performed safely. Angioplasty and stenting is feasible, and can improve cerebral perfusion even in a patient with multiple severe atherosclerotic stenoses by pre-operative appropriate haemodynamic assessment.

Nonviable gram-negative bacilli were seen in smears of cerebrospinal fluid from eight infants in whom bacterial meningitis was ruled out. Tubes from commercial kits were the source of the factitious organisms.

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The bicyclic ketone (Ia) reacts with trimethylchlorosilane (II) after lithiation to give the bridgehead substitution product (Ib).