Serological survey of antibody to Neospora caninum in Japanese dogs

Prevalence of antibody to Neospora caninum (NC) in Japanese dogs were examined. The antibody was positive in 15 of 48 dogs (31.3%) reared in the dairy farms that had case of the abortions due to NC infection or had the cattle seropositive to NC, whereas the prevalence was 7.1% (14 of 198 dogs) among the dogs kept in urban areas. In one dog breeder, all 17 Shetland sheepdogs older than 7 months were seropositive, and one pup was diagnosed as neosporosis 2 months before the first serological examination. The antibody titers of the dogs kept at this breeder were almost unchanged for 1.5 years. Serological evidence of the dogs in the dairy farms and urban areas indicates the transmission of NC between dogs and cattle. Also serological results of the dogs in one breeder may suggest the potential horizontal transmission among dogs.     

Preparation and phase transition of Gd4(Al1 − xGax)2O9 solid solutions

The solid-solution compounds of Gd₄(Al_{1 – x} Ga _x )₂O₉ (x = 0.0–1.0) were prepared at 1600°C for 5 h in air. The unit cell volume of the compounds increased from 0.853 to 0.878 nm³ with x. Phase transitions having a temperature hysteresis were observed from 1100° to 1400°C by calorimetry and dilatometry. The transition temperature increased with x. The volume of the high-temperature phase was 0.5% smaller than that of the low-temperature phase at the transition temperature. The volume changes were independent of x. The hysteresis width observed by the dilatometry was about 300°C for the Gd₄Al₂O₉ ceramics (grain size: about 1 m) and decreased to 50°C for the Gd₄(Al_0.2Ga_0.8)₂O₉ ceramics (grain size: over 10 m). Gd₄Ga₂O₉ was unstable at low temperature and decomposed to Gd₃GaO₆ and Gd₃Ga₅O₁₂ during the thermal analyses.     

TAK-603 selectively suppresses Th1-type cytokine production and inhibits the progression of adjuvant arthritis

Lipopeptides carrying a farnesyl thioether or a palmitic acid thioester and a farnesyl thioether were prepared from S-farnesyl cysteine methyl ester by N-terminal extension of the peptide chain employing the base labile Fmoc blocking group of the palladium(0) sensitive Aloc urethane. By means of this technique a lipohexapeptide representing the completely functionalized, i.e. palmitoylated and farnesylated C-terminus of the human N-Ras protein, was prepared. If acid labile blocking functions like the Boc group were used, upon deprotection an undesired addition of the acid to the double bonds of the farnesyl residue occurred. Therefore, acid labile blocking groups should not be employed in the synthesis of farnesylated lipopeptides. The lipopeptide methyl esters which carry only a farnesyl group do not inhibit protein farnesyl transferase, whereas palmitoylated peptides are weak inhibitors of this enzyme.     

Hot-Carrier-Related Increase in Drain Resistance and Its Suppression by Reducing Contaminants in InP-Based HEMTs

We examined the issue of reliability of InP-based high-electron mobility transistors (HEMTs), focusing on the increase of drain resistance R_d. In investigations of the mechanism of R_d increase, we took note of contaminant incorporation and of the relations between the device lifetime and the strength of the channel electric field. In the fabrication process, reducing contaminants, especially fluorine, significantly suppressed the increase of source and drain resistances. Cross-sectional views of the gate of improved devices, which had a long lifetime, confirmed an almost contaminant-free surface around the gate. In acceleration tests, the most negative impact on drain resistance stability among several bias conditions was found when the current density was high and the channel electric field was large at the same time. The dependence of drain-gate electric field strength E showed that the device lifetimes of HEMTs determined from R_d increase obeyed exp(1/E), which means that impact ionization was the main cause of degradation. We elucidate that the interactions of hot carriers with contaminants around the gate are the main causes of the R_d increase in HEMTs. Suppression of device degradation was achieved by optimizing the fabrication process around the gate. In this way, device lifetime was remarkably enhanced.     

Measurements of fiber bundle interfacial properties of three-dimensionally reinforced carbon/carbon composites up to 2273 K

Experimental techniques for evaluating the interfacial properties between fiber bundles and the matrix of three-dimensionally reinforced carbon/carbon composites were examined. Specially arranged fiber bundle push-out and pull-out tests were conducted up to 2273 K in vacuum. In these tests, a fiber bundle in the specimens was extruded or pulled out by external compressive or tensile loads. Post-fracture observations revealed that a shear fracture was successfully induced within the carbon matrices at the loaded fiber bundle interface. The interfacial shear strength and initial sliding stress of the fiber bundle monotonically increased with the test temperature. The relief of residual thermal stress and increases in the frictional resistance and anchor effect at the fiber bundle interface were considered to be the major mechanisms that caused the enhancements. An increase in the heat treatment temperature during the processing of the composites resulted in a significant decrease in and .     

Compression molding and melt‐spinning of the blends of poly(lactic acid) and poly(butylene succinate‐co‐adipate)

Poly(lactic acid) (PLA) is a biobased polymer made from biomass having high mechanical properties for engineering materials applications. However, PLA has certain limited properties such as its brittleness and low heat distortion temperature. Thus, the aim of this study is to improve toughness of PLA by blending with poly(butylene succinate‐co‐adipate) (PBSA), the biodegradable polymer having high toughness. Polymer blends of PLA and PBSA were prepared using a twin screw extruder. The melt rheology and the thermal property of the blends were examined. Further the blends were fabricated into compression molded parts and melt‐spun fiber and were subjected to tensile and impact tests. When the PBSA content was low, PBSA phase was finely dispersed in the PLA matrix. On the other hand, when the PBSA content was high, this minor phase dispersed as a large droplet. Mechanical properties of the compression molded parts were affected by the dispersion state of PBSA minor component in PLA matrix. Impact strength of the compression molded parts was also improved by the addition of soft PBSA. The improvement was pronounced when the PBSA phase was finely dispersed in PLA matrix. However, the mechanical property of the blend fibers was affected by the postdrawing condition as well as the PBSA content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41856.