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Bronze based alloys have come to be used as bearing materials, and require low frictional properties. The present study describes the effects of surface finish machining history on the on tribological properties of sulfide-containing bronze sintered onto a steel disc. The sulfide phase consisted of copper, iron and sulfur, and acted as a solid lubricant. The relative density of the specimen was 90 % and the microstructure showed that the micro-sized sulfide dispersed into the bronze matrix and was accompanied by pores. Various processes, including cutting, burnishing, polishing were, applied to finish the surface. It was found that the area fraction of the sulfide phase depended on the cutting conditions. A further increase in the area fraction was achieved using roller burnishing after the cutting. Tribological properties were evaluated using chromium alloy steel (SUJ2) as the mating surface under dry conditions. The results showed that the friction coefficient depended on the surface finishing process. Therefore, the machining history had an effect on the frictional properties of the sulfide-containing bronze. Optimal cutting conditions for the sulfide containing bronze are also discussed.

Cu alloys such as bronze have long been used as bearing materials because of their good run-in properties for steels used as mating materials. These Cu alloys are also suitable for various applications: High-strength brass castings and phosphorus bronze castings are used for their ability to obtain higher strengths, whereas Pb–bronze castings are used for anti-seizure applications. To prevent scoring and seizure, base materials such as Cu alloys were often combined with a solid lubricant. In this study, the tribological properties of sulfide-dispersed bronze were investigated. Friction tests were conducted under dry conditions for bronze with/without sulfides. It was found that seizure was prevented in sulfide–bronze systems only under certain test conditions. It was estimated that the dispersed sulfide restricted the transfer of the Cu alloy elements to the mating steel surface. Moreover, the addition of Si to a Cu–Fe–S system and to sulfide-dispersed bronze resulted in crystallization of Fe–Si compounds. The hardness and anti-wear properties of the compounds were also improved.

The present study describes the tribological properties of a bronze alloy used as a sliding interface for operation under dry conditions. Many industrial slide bearings are made from bronze alloy. To achieve easy running-in and enhanced anti-seizure, solid lubricants are added to the alloys. However, it is difficult to simultaneously achieve easy running-in and anti-seizure with one solid lubricant. Thus, the combined effects of a solid lubricant and a dispersed sulfide layer on reducing and stabilizing the friction coefficient were also examined. The tribological properties of the resulting alloy were evaluated with a 3-ball on disc type testing apparatus under dry conditions and in air atmosphere. The surface state of the solid lubricant and dispersed sulfide layer was evaluated by observation of the morphology and phase states via atomic force microscopy. Distinctive features of a phase comprising mixed stiff and soft regular regions on the micrometer scale were observed. These two regular regions are considered to be formed from graphite and sulfide by burnishing. The effect of the dual phase state leads to achievement of both easy running-in and anti-seizure.

Tribological properties of copper based porous alloy with penetrated micro size graphite layer were evaluated using a ring on disc testing apparatus in dry condition. A shot peening treatment was applied to ensure the dimple for the graphite penetration. Specimens with various area fraction of the graphite layer were prepared. It was found that the friction coefficient and the wear loss decreased with the increase in the area fraction. However, the decrease of the friction and the wear loss became smaller at excess graphite area fraction.

A lead-free bronze alloy powder with a dispersed sulphide solid lubricant phase has been produced by atomisation as a substitute for lead bronze friction materials. The powder has been processed to produce a bronze/steel bimetal strip by a sinter/roll/sinter process route, via both solid state and liquid phase sintering. Friction properties of the developed materials and a sintered bronze were compared in pin-on-disc tests; the Cu–Sn–S material shows excellent properties, equivalent to those of a lead bronze, and is being assessed for use in high pressure bushes.

A total of 548 upper limbs (276 right and 272 left hands) from Japanese cadavers were dissected. The arrangements of extensor indicis proprius, extensor digitorum communis (EDC), and extensor digiti minimi tendons and the intertendinous connections were studied. The most common pattern of extensor tendons was as follows: the index finger had a single EDC tendon, the middle finger had a single EDC tendon, the ring finger had a single EDC tendon, and the small finger had a single EDC tendon or a single common EDC tendon distributed to the ring and small finger. A single extensor indicis proprius tendon ran along the ulnar side of the EDC, and the extensor digiti minimi tendon consisted of 2 slips. Intertendinous connections were classified into 3 types: type 1 with a filamentous band, type 2 with a fibrous band, and type 3 with a tendinous band subdivided to r-shaped and y-shaped. The most common patterns were type 1 in the second intermetacarpal space (IMCS), type 3r in the third IMCS, and type 3y in the fourth IMCS.

Ten cases of de Quervain disease were examined by ultrasound. Three were treated with surgical method. Ultrasound examinations were performed with 7.5MHz transducers. We classified the patterns of the septum in the first extensor compartment of the wrist into three groups, complete type, incomplete type, and no septum type. According to this classification, seven cases were of the incomplete type, and the other three cases were of no septum type. Three cases treated with the operative method were of the incomplete type. Ultrasound examination seems to be useful for the diagnosis of the Quervain disease.

We have studied 35 patients (25 female and 10 male) with low-back pain who were managed with aquatic exercises after an appropriate period of treatment for their condition in the medical institution. The exercises employed consisted of strengthening exercises for the abdominal, gluteal, and leg muscles, stretching of the back, hip, hamstrings, and calf muscles, walking in water, and swimming. All the patients had been participating in the exercise program for more than 6 months. The frequency of performing exercises was once a week for 7 patients, twice a week for 19, and 3 or more times a week for the remaining patients. The method used in this study was a survey questionnaire which was composed of questions about the patient's physical and psychological condition. Those patients who had performed exercises twice or more in a week showed a more significant improvement in the physical score than those who performed exercises only once a week. More than 90% of the patients felt they had improved after 6 months of participation in the program. The improvement in physical score was independent of the initial ability in swimming. The results obtained suggested that exercises in water may be one of the most useful modes of exercise for a patient with low-back pain.

Compounds 3 , the C/D ring moiety of paclitaxel without a 7-hydroxyl group, and 4 , the C ring moiety of O -cinnamoyltaxicin-I ( 2 ), were synthesized stereoselectively from methyl ( E , S )-3-(2,2-dimethyl-1,3-dioxolan-4-yl)-2-pentenoate ( 5 ) using the fragmentation reaction of bicyclo[2.2.2]octane derivative 9 as a key step to give 10 .

Between 1978 and 1995, 98 total hip arthroplasties (THA) and 142 total knee arthroplasties (TKA) were carried out in 152 patients with rheumatoid arthritis (RA). Multiple joint arthroplasties (three or more joints) were performed on 30 THAs and 31 TKAs in 17 patients with RA. The mean age was 51.4 years at the first operation and 56.4 years at the final surgery. The mean interval between each surgery was 4.5 years.Of the 16 rheumatoid patients, 11 improved to independent ambulation, 2 deteriorated to limited ability, one was confined to a wheelchair and 2 had died. General complications were found in 8 patients (14.1%), but they did not influence the patient's life span. There were a few local complications (28%) resulting from the total 57 arthroplastic procedures and 11 joints required reoperation.Surgical therapy plays an important part in management of RA once joint destruction has occurred, and therefore arthroplasty must be considered as soon as possible.

Many industries have developed new materials as substitutes for lead in solid lubricants. For example, lead bronze, a Cu-Pb alloy that has been used for slide bearings, has been replaced by a Cu alloy containing sulfide. The development of Pb-free Cu alloys has received considerable attention recently. Pb and sulfide are types of solid lubricants; in particular, MoS2 (molybdenum disulfide) is a popular sulfide lubricant. This study focuses on a material that contains Cu2S. The properties of Cu2S as a solid lubricant are unknown. First principles (FP) and molecular dynamics (MD) are used to clarify the lubrication mechanism of Cu2S. The atomiclevel stable structure of Cu2S is evaluated by FP under specific sliding conditions. The Cu2S lubrication mechanism is clarified by MD using the FP results for the interatomic potential functions. It is clarified that there is a specific slip system and the Cu-S bonds that exists above and below the layers of the slip system are very strong.

For successful total knee arthroplasty (TKA), it is very important to gain an accurate grasp of the mechanical axis of the lower limb and establish a suitable ligament balance. Recently, TKA using navigation systems has been developed to accomplish more accurate component placement and to achieve a better understanding of the mechanical axis. The purpose of this study was to compare the radiological results of computer-navigated TKA with those of conventional TKA. We prospectively evaluated 75 primary TKAs (75 subjects) that were performed using a cruciate-retaining prosthesis of the same model at our institution. The subjects were allocated alternately to a navigation group (37 knees) and a conventional group (38 knees). Postoperative radiographs were taken in the standing position at 12 weeks after surgery, and were evaluated in accordance with the report of Bathis et al. [1]. No significant difference in preoperative profiles was observed between the two groups. At the postoperative radiographic evaluation, significantly better results were obtained in the navigation group with regard to the mechanical axis and the component, but the results were less conclusive in the lateral femoral component position. Our findings suggest that computer-navigated TKA is useful for obtaining more accurate results. However, the present study was limited by the small number of subjects and short follow-up period, and therefore further study involving more subjects and a longer-term follow-up will be needed.

Cycloadditions of the title compounds with dimethyl acetylenedicarboxylate gave 1:2-cycloadducts. The structural assignments of the products were deduced by spectral inspections; the structure for one compound was established by X-ray crystallography.

The reactions of 2- and 8-(substituted amino)-1-azaazulenes with dimethyl acetylenedicarboxylate (DMAD) were investigated. Treatment of ethyl 2-acetylamino-1-azaazulene-3-carboxylate with DMAD in refluxing acetonitrile gave 9-ethyl 1,2,3-trimethyl 3a-azacyclopent[a]azulene-1,2,3,9-tetracarboxylate, 5-ethyl 1,2,2a,3-tetramethyl 4-acetyl-2a,3-dihydro-4H-4, 10b-diazapentaleno[1,6-aj]azulene-1,2,2a,3,5-pentacarboxylate (3a), and dimethyl (10-ethoxycarbonyl-4-methoxycarbonyl-2,4a-dihydro-2-oxo-2H-1,4a-diazabenz[a]azulen-3-yl)maleate. Compound 3a thermally rearranged to 9-ethyl 2,3,10,11-tetramethyl 1-acetyl-2,3,4,4a-tetrahydro-1H-1,4-diaza-3,4a-ethenofluorene-2,3,9,10,11-pentacarboxylate. The reaction of ethyl 2-alkylamino-1-azaazulene-3-carboxylate with DMAD gave the corresponding 4-alkyl-2a,3-dihydro-4H-4,10b-diazapentaleno[1,6-aj]azulene derivatives, and the etheno-bridged 1-azaheptalene derivative. The reaction of 8-ethylamino-3-phenyl-1-azaazulene with DMAD gave trimethyl 1-phenyl-2a-azabenz[cd]azulene-3,...

The reactions of 2- and 8-(substituted amino)-1-azaazulenes with dimethyl acetylenedicarboxylate (DMAD) were investigated. Treatment of ethyl 2-acetylamino-1-azaazulene-3-carboxylate with DMAD in refluxing acetonitrile gave 9-ethyl 1,2,3-trimethyl 3a-azacyclopent[a]azulene-1,2,3,9-tetracarboxylate, 5-ethyl 1,2,2a,3-tetramethyl 4-acetyl-2a,3-dihydro-4H-4, 10b-diazapentaleno[1,6-aj]azulene-1,2,2a,3,5-pentacarboxylate (3a), and dimethyl (10-ethoxycarbonyl-4-methoxycarbonyl-2,4a-dihydro-2-oxo-2H-1,4a-diazabenz[a]azulen-3-yl)maleate. Compound 3a thermally rearranged to 9-ethyl 2,3,10,11-tetramethyl 1-acetyl-2,3,4,4a-tetrahydro-1H-1,4-diaza-3,4a-ethenofluorene-2,3,9,10,11-pentacarboxylate. The reaction of ethyl 2-alkylamino-1-azaazulene-3-carboxylate with DMAD gave the corresponding 4-alkyl-2a,3-dihydro-4H-4,10b-diazapentaleno[1,6-aj]azulene derivatives, and the etheno-bridged 1-azaheptalene derivative. The reaction of 8-ethylamino-3-phenyl-1-azaazulene with DMAD gave trimethyl 1-phenyl-2a-azabenz[cd]azulene-3,...

Medium ring compounds (9 to 11 membered rings) having endo (E or Z) and exo double bonds at 1,5-positions were synthesized by intramolecular cyclization of the ω-functionalyzed allylic anion stabilized by a sulfur atom. The yields of cyclization were related not only with the cyclization enthalpy (steric strain of the resultant cyclic compounds) but also with entropy factor.

CASE REPORT A 22-year-old man was hit in the right shoulder in a traffic accident. He felt right shoulder pain 6 months after the accident and visited a physician for a careful checkup, but no definite diagnosis was established. The patient complained of continuous pain at night and underwent a diagnostic arthroscopy. No intra-articular pathology was seen. He was referred to our hospital because of persistent shoulder pain. On the patient’s initial visit to our hospital, he complained of pain around the right shoulder. The pain was worse at night and improved with anti-inflammatory medication. The range of motion was not restricted. No swelling, tenderness, or local heat around the shoulder was noted. Blood examination showed normal inflammatory markers. The remainder of the clinical examination was unremarkable. Plain radiographs taken 12 months earlier showed no tumor lesion (Figure 1). Plain radiographs at this time showed a radiolucent area surrounded by a sclerotic band (nidus) at the greater tuberosity (Figure 2). Fat suppression T2-weighted magnetic resonance (MR) arthrograms disclosed a small, rounded, highintensity area surrounded by a low-intensity ring at the same site (Figure 3). Computed tomography (CT) scan confirmed a small calcification surrounded by low-attenuation area (Figure 4). The tumor was curetted with a fine needle under fluoroscopic guidance. Histologic examination showed an interlacing network of osteoid trabeculae, consistent with an osteoid osteoma. Three years after the operation, the pa

This report describes two arterial anomaly cases in the celiaco-mesenteric region, which were encountered in two Japanese male cadavers in the dissecting room at Kurume University School of Medicine in 1999. In these cases, the usual celiac trunks were not identified, and the hepato-mesenteric and the gastro-splenic trunks were independently arising from the abdominal aorta. Moreover, in the first case, the common hepatic artery passed ventral side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type V of Adachi's classification and the Type IV' of Morita's classification. In the second case, the common hepatic artery passed dorsal side of the portal vein and divided into the hepatic proper and the gastroduodenal arteries. This type of arterial anomaly belongs to the Type VI of Adachi's classification and the Type IV' of Morita's classification.

This report describes an arterial anomaly case in the celiaco-mesenteric region, which was encountered in a Japanese male cadaver in the dissecting room at Kurume University School of Medicine in 1999. In this case, the usual celiac trunk was not identified, and the hepato-spleno-mesenteric and the gastro-phrenic trunks were independently arising from the abdominal aorta. In addition, the common hepatic artery divided into the left hepatic, the right hepatic, and the gastroduodenal arteries simultaneously, then, the accessory gastric artery arose from the left hepatic artery. This type of arteral anomaly belongs to the Type III of Adachi's classification and the Type II of Morita's classification.

Cycloadditions of the title compounds with dimethyl acetylenedicarboxylate gave 1:2-cycloadducts. The structural assignments of the products were deduced by spectral inspections; the structure for one compound was established by X-ray crystallography.

Medium ring compounds (9 to 11 membered rings) having endo (E or Z) and exo double bonds at 1,5-positions were synthesized by intramolecular cyclization of the ω-functionalyzed allylic anion stabilized by a sulfur atom. The yields of cyclization were related not only with the cyclization enthalpy (steric strain of the resultant cyclic compounds) but also with entropy factor.