Effects of TRI-n-butyl phosphate on pregnancy in rats

A teratological study was carried out on the plasticizer tri-n-butyl phosphate (TBP). Pregnant Wistar rats were treated orally on days 7-17 of gestation with TBP at 0, 100, 200, 400 or 800 mg/kg/day in the dose-finding study and 0, 62.5, 125, 250 or 500 mg/kg/day in the subsequent teratological study. Caesarean sections were performed on day 20 of gestation. In the dose-finding study, all of the pregnant rats were killed by the treatment with TBP at 800 mg/kg/day. In the teratological study, salivation and depression of body weight gain, adjusted body weight gain and food consumption were observed at the higher doses of TBP. There were no significant differences between the groups in the incidence of dead or resorbed foetuses, the number of living foetuses and the body weights of living foetuses of both sexes. The incidence of rudimentary lumbar rib increased significantly at 500 mg/kg/day. There were two cases of malformation: a foetus with deformity of fore- and hind-limbs at 400 mg/kg/day in the dose-finding study and conjoined twins exhibiting three fore-limbs and four hind-limbs at 125 mg/kg/day in the teratological study. These malformations were rare in the background data of teratology, and the incidence of foetuses with malformations was not increased significantly. Therefore, TBP was considered not to be teratogenic in this study.     

Isolation of MHC class I-restricted tumor antigen peptide and its precursors associated with heat shock proteins hsp70, hsp90, and gp96

We have previously demonstrated that vaccination with heat shock proteins hsp70, hsp90, and gp96 elicits specific immunity against the tumor from which the hsps were purified. Although the association of tumor Ag peptides with these hsps have been suggested, the identification of the peptides or their precursors stripped from the hsps remained to be resolved. We show in this report that an Ld-restricted cytotoxic T lymphocyte epitope of a mouse leukemia RLmale symbol1 and its precursors are associated with the chaperones hsp90 and hsp70 in the cytosol and gp96 in the lumen of the endoplasmic reticulum. Hsp70 was associated with only final sized octamer, while hsp90 was found to associate with the octamer and two distinct precursor peptides. The gp96 was associated with the octamer and one of the two precursors. Thus, each of the hsps bound a distinct set of peptides. Our results have demonstrated for the first time that the hsps associate not only with final sized tumor Ag peptide but also with its precursors. The implication of this evidence is also discussed in terms of the roles of hsps in MHC class I Ag processing/presentation.     

Numerical simulation for diffusion of matter in compound round jet by three-dimensional particle method

A three-dimensional particle method for the diffusion of matter in a round jet is proposed. The flow field is calculated with a vortex method, whereas the concentration field is simulated through a method analogous to the vortex method. The particle method is based on the Lagrangian approach; thus no computational grids are needed. It is applied to simulate the diffusion of matter in a compound round jet. The large-scale eddies, appearing just downstream of the disappearing point of the potential core, cause the diffusion of matter in the radial direction. In the subsequent developed region of the velocity field, the diffusion proceeds to the smaller vortical structure. The mean concentration and the concentration fluctuation intensity are in the self-preservation state at x/D?8 and x/D?13, respectively. These numerical results are favorably compared with experimental ones, indicating that the present particle method is usefully employed to simulate the diffusion of matter in a round jet.     

Synthesis of supramolecular solid polymer electrolytes via self-assembly of diborylated ionic liquid

Novel supramolecular type solid polymer electrolytes were prepared by self-assembly of diborylated ionic liquid in the presence of bifunctional ligands. The polymers obtained were well soluble in methanol, and their structures were supported by ¹H and ¹¹B NMR spectra. The ionic conductivity of the polymers was evaluated by ac-impedance method after the samples were dried thoroughly. The ionic conductivity observed was 8.8 × 10⁻⁶ to 5.4 × 10⁻⁶ S cm⁻¹ at 51 °C in the presence of equimolar amount of LiTFSA to ionic liquid unit. The temperature dependence of ionic conductivity was successfully fitted to VFT (Vogel-Fulcher-Tamman) plots, indicating that ionic conduction is taking place according to typical ion transport model in viscous matrix.     

Interaction of cyclodextrins with side chains of water soluble polymers: A simple model for biological molecular recognition and its utilization for stimuli-responsive systems

This article demonstrates that the interaction of cyclodextrins (CDs) with side chains of water soluble polymers is useful not only as simple models for biological molecular recognition but also as building blocks in nanotechnological applications. In the interaction of CDs with polymer side chains, the selectivity of CDs was enhanced by the steric effect of the polymer main chain and by interaction at multi-sites (i.e., collectivity). Utilizing the interaction of CDs with polymer side chains, stimuli-responsive systems were constructed from simple components.     

Effect of Surface Roughening of Substrate Steel on the Improvement of Delamination Strength and Tribological Behavior of Hydrogenated Amorphous Carbon Coating Under Lubricated Conditions

The adhesion strength of diamond-like carbon (DLC) coatings is an obstacle in efforts to improve the reliability of coated products. It is generally believed that the roughening of the substrate surface improves the adhesion between a substrate and coating. The effect of surface roughening of the substrate on the delamination strength of DLC coating and the tribological behavior under lubrication were studied. Five types of roughened substrates were prepared by a wet blast device with differing materials, shapes, and sizes of the shot particles. A hydrogenated DLC film was deposited using plasma-enhanced chemical vapor deposition on the roughened substrates. The tribological properties were investigated under air and lubrication with pure water or n-decane. It was found that the delamination strength of the DLC coating could be improved by roughening the substrate surface, especially by spherical particles. It was also found that slight polishing of either the DLC surface deposited on the rough substrate or the roughened substrate before deposition significantly reduced the wear of the counter surface. The remaining chemical element of alumina particles on the roughened surface affected the delamination strength of the DLC coating.     

Anthropogenic effects on the subsurface thermal and groundwater environments in Osaka, Japan and Bangkok, Thailand

Anthropogenic effects in both Osaka and Bangkok were evaluated to compare the relationships between subsurface environment and the development stage of both cities. Subsurface thermal anomalies due to heat island effects were found in both cities. The Surface Warming Index (SWI), the departure depth from the steady geothermal gradient, was used as an indicator of the heat island effect. SWI increases (deeper) with the magnitude of heat island effect and the elapsed time starting from the surface warming. Distributions of subsurface thermal anomalies due to the heat island effect agreed well with the distribution of changes in air temperature due to the same process, which is described by the distribution of population density in both Osaka and Bangkok. Different time lags between groundwater depression and subsidence in the two cities was found. This is attributed to differences in hydrogeologic characters, such as porosity and hydraulic conductivity. We find that differences in subsurface degradations in Osaka and Bangkok, including subsurface thermal anomalies, groundwater depression, and land subsidence, depends on the difference of the development stage of urbanization and hydrogeological characters.     

Determination of mechanical properties of impacted human morsellized cancellous allografts for revision joint arthroplasty

This paper deals with the characterization of mechanical properties of impacted morsellized cancellous allograft (IMCA) produced by dynamic compaction of allograft femoral heads ground by commercially available bone mills, i.e. rotating rasp and reciprocating type bone mills. Various ranges and profiles of particle size in the graft aggregates were obtained using these bone mills, and the effect of number of compaction as well as the distribution of particle sizes on the mechanical properties of IMCA under quasistatic compression and shear loading conditions was discussed. The morsellized cancellous allograft prepared by the reciprocating type bone mill showed a broad distribution of particle sizes, and gave IMCA superior mechanical properties to the graft with a more uniform size distribution, or prepared by the rotating rasp type bone mills. The increase of number of compaction also improved the mechanical properties of IMCA in compression.     

Cooperative Control of a 3D Dual-Flexible-Arm Robot

This paper discusses cooperative control of a dual-flexible-arm robot to handle a rigid object in three-dimensional space. The proposed control scheme integrates hybrid position/force control and vibration suppression control. To derive the control scheme, kinematics and dynamics of the robot when it forms a closed kinematic chain is discussed. Kinematics is described using workspace force, velocity and position vectors, and hybrid position/force control is extended from that on dual-rigid-arm robots. Dynamics is derived from constraint conditions and the lumped-mass-spring model of the flexible robots and an object. The vibration suppression control is calculated from the deflections of the flexible links and the dynamics. Experiments on cooperative control are performed. The absolute positions/orientations and internal forces/moments are controlled using the robot, each arm of which has two flexible links, seven joints and a force/torque sensor. The results illustrate that the robot handled the rigid object damping links' vibration successfully in three-dimensional space.