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Polymer cement mortar (PCM) retrofitting is one of the largely used strengthening methods for repairing fatigue deteriorated highway bridge slabs in Japan. In this method, reinforcing bars are arranged underneath the lower surface of the slab and polymer cement mortar is sprayed onto them. Debonding of the PCM overlay is one of the major causes leading to failure of the repaired slabs. This paper mainly discusses this failure mechanism, its initiation, and suggests a method for quantitative analysis of the failure behavior. The stress transfer mechanism was measured using the strain distribution in the strengthening bars and a relationship for the bonding strength was obtained. Hence the relationship for the peeling load was obtained.

We report the case of a 72-year-old man with esophageal schwannoma who underwent the Ivor Lewis procedure. He suffered from dysphagia for 6 months. Esophagoscopy revealed a submucosal tumor bulging on the posterior wall 30 cm distant from the incisors. Endoscopic ultrasonography (EUS) revealed tumor located within the muscularis propria, the fourth layer of the esophageal wall. Upper gastrointestinal series showed an elevated lesion, 6 cm in diameter, on the posterior wall of the upper thoracic esophagus. These findings were suggestive of leiomyosarcoma. The area of esophagus including the tumor was resected using the Ivor Lewis procedure. The tumor was 5.5 × 4.5 × 4.5 cm in size, with a smooth surface that was elastic and firm. Histological examination revealed spindle-shaped cells with oval nuclei, and Antoni A and B types coexisted in the tumor tissue. Immunohistochemical studies yielded positive results for S-100 protein and negative results for CD34, desmin, and α-smooth muscle actin. A diagnosis of esophageal schwannoma was established. He was discharged from the hospital and has been doing well with no recurrence for 20 months after surgery.

ポリマーセメントモルタル増厚工法により補強された部材は, 補強構造と荷重の載荷状況により, 終局的に剥離を伴う破壊性状を示す. 本研究ではコンクリート試験体に補強筋とポリマーセメントモルタルを用いて増厚を行い, 接着界面の面内にせん断力を作用させ, この条件で生じる付着性状を実験的に解明し把握したものである. すなわち本工法の応力伝達機構を補強筋と増厚材のひずみ分布から把握し, 付着強度算定式の同定を行った. また, ポリマーセメントモルタル増厚工法に関しても付着界面のずれ量と付着応力度から同定した剥離破壊エネルギー算定式により, 剥離破壊エネルギーの算定が可能であることを示した.

UNLABELLED We estimated the effect of d-tubocurarine (dTc) on neuromuscular transmission and the action of propofol on dTc-induced twitch depression by using sham control and septic rat nerve-hemidiaphragm preparations in vitro. Isometric twitch tension elicited by indirect (phrenic nerve) or direct (muscle) stimulation at 0.1 Hz was evaluated. Sepsis induced by panperitonitis attenuated the twitch tension elicited by indirect and direct stimulation (P < 0.01 in each group) in the absence of significant morphological inflammatory damage to the diaphragm. dTc (1 microM) decreased the twitch tension elicited by indirect stimulation (P < 0.01) less intensely in the septic group than in the sham group (P < 0.01). Propofol accentuated dTc-induced depressed twitch more intensely in the septic group (P < 0.01 or 0.05). These results demonstrate that sepsis attenuates both muscle contractile force and the effect of a neuromuscular blocker and that propofol more intensely enhances dTc-induced twitch depression during sepsis. IMPLICATIONS Propofol and nondepolarizing muscle relaxants are widely used for various clinical cases, including sepsis. Interactions between nondepolarizing muscle relaxants and propofol during sepsis are interesting from a clinical point of view. We demonstrated that propofol significantly enhances d-tubocurarine-induced twitch depression in vitro in the septic rat model compared with that in the nonseptic rat model.

The static and fatigue strengths of ultrahigh-strength steel sheets and ultrahigh-strength steel sheet and lower-strength steel sheet joined by spot welding were investigated. The tensile shear strength of the joint of ultrahigh-strength sheets was lower than the estimated value calculated by estimate equations with the increase in the tensile strength of the base steel, because of the existence of the heat affected zone strength of which was relatively lower than that of the base steel. The tensile shear strength of the joint of ultrahigh-strength sheet and lower-strength sheet depended on the tensile strength of the lower-strength steel. The fatigue strength of the tensile shear mode did not depend on the tensile strength of the base steel. It showed almost a constant value with a change of tensile strength of the base steel. The fatigue strength of the cross tension mode is showed the same tendency as the case of the tensile shear mode. The fatigue strength of the bending mode also showed the same tendency. The fatigue strength did not change with the change of tensile strength of base the steel. But the appearance of fractures were different from each other. Cracks propagated into the ultrahigh-strength side in the case of the tensile shear mode and cross tension mode, but in the case of the bending mode they propagated into the lower strength side.

Fluoroethers neither destroy the ozone-layer nor promote greenhouse effect. We found that treatment of HCFC22 with sodium methoxide or methanolic sodium hydroxide yielded fluoroether, CH 3 OCHF 2 . Vapor pressure measurements suggested that fluoroethers were expected as alternative refrigerants of HCFC142b.

Diffusion coefficients and solubility of helium, neon and argon gases in ice crystals were determined by measuring the pressure rise in a vessel caused by gas emission from an ice sample supersaturated with the gas. Diffusion coefficients of helium, neon and argon gases in the temperature range between 258.2 K and 268.2 K were on the order of (10)^m^2s^, (10)^m^2s^ and (10)^m^2s^, respectively. Solubilities of helium and neon gases in the molar fraction deduced from the total amount of emitted gases were on the order of (10)^ and (10)^, respectively. As the diffusion coefficients of noble gases were found to depend on their molecular radii, the diffusion coefficients of air molecules, such as nitrogen and oxygen, in ice were estimated.

Poisoning by air of Mm 0.9 Y 0.1 Ni 4.9 Mn 0.1 and LaNi 4.55 Al 0.45 alloys with CaCu 5 structure was studied to clarify their applicability to refrigeration systems. The decrease in hydrogen capacity on hydrogen absorption-desorption cycling with air contamination was limited to a certain degree under an extended air concentration up to 1.0 vol.%. The poisoned alloys recovered their hydrogen-absorbing capacity on reactivation treatment. These results and X-ray powder diffraction analysis suggest that the degradation was not caused by complete oxidation. Thus, we propose that the degradation is caused by adsorption of oxygen in air, and that the poisoned state is an intermediate state which is more stable than the adsorption equilibrium state but less stable than the oxidation state. Poisoning by adsorption was analyzed using Langmuir's adsorption theory to explain the relations between the degradation rate and concentration of air.

Chlorinated compounds such as CFCs and carbon tetrachloride are considered to deplete the stratospheric ozone layer. An anti-pollution process to remove chlorine from these compounds at room temperature using sodium alcolate or NaOH-alcohols with UV irradiation is proposed.

A 33-year-old Japanese male was admitted to our hospital for the treatment of left pneumothorax. He was found to have bilateral giant bullae. Retention of fluid was observed in the right giant bulla. The fluid accumulated rapidly directly after bullectomy and excision of the left giant bullae. This suggested the existence of some mechanisms of fluid retention other than an infection of the bulla alone after operation.

Measurements of diffusion coefficients of He gas and N_2 gas in ice crystals were carried out under the high pressure and atmosphere pressure. The understanding of diffusion phenomena of air molecules in ice is important on studying palaeo-environments by polar ice core analysis. But the measurements of gas molecules diffusion in ice have been done only for He and Ne. Thus we developed an apparatus to measure the diffusion coefficient of gas molecules in ice. In order to estimate the accuracy of this apparatus, the diffusion coefficient of He gas is measured. Measurements of N_2 gas, which is the main constituent of air, were carried out. The diffusion coefficients were measured by the change of gas pressure in the sample cell. In this study a precise differential pressure transducer was used for measuring the small pressure change under high pressure caused by the diffusion of gas molecules in ice samples. All measurements were carried out at 263 (±0.1) K. The diffusion coefficients of He gas molecules in an ice single crystal are 1.5 (±0.6)×(10)^ and 1.6(±1.0)×(10)^(cm)^2/s at 47.5 and 69.5 atm, respectively. Under atmosphere pressure, it is 1.9 (±0.6)×(10)^(cm)^2/s. These results agree with the results obtained by J HAAS et al. (Solid State Commun., 9,2033,1971). Therefore it is estimated that this apparatus can measure diffusion coefficients of more than about (10)^(cm)^2/s. The diffusion coefficient of N_2 gas molecules in an ice polycrystal is 1 (±1)×(10)^(cm)^2/s, at atmosphere pressure. In a single crystal of ice it cannot be measured. N_2 gas molecules can be considered to diffuse with less than (10)^ (cm)^2/s of diffusion coefficient in a ice single crystal. These results indicate that N_2 gas molecules in ice diffuse along grain boundaries faster than in the lattice. The obtained diffusion coefficient of N_2 gas also indicates that air molecules in a deep ice sheet can be estimate to diffuse about 20 m during 100 kyr if they diffuse only along grain boundaries.