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Carbon fiber reinforced plastic (CFRP) is used in various industries because of its high specific strength, but it is well known as a difficult material to cut. In this study, we developed a disc-shaped electrodeposited diamond wire mesh grinding wheel as a new method for cutoff and grooving with a large aspect ratio for CFRP. We confirmed that this tool could be used for machining at a feed rate of 1000 mm/min, equivalent to that of an abrasive waterjet. This tool discharges generated chips through the spaces in the wire mesh, preventing clogging and thereby enabling the suppression of machining temperature. No burrs or delamination were observed on the surface machined with the wire mesh grinding wheel, and the surface roughness was Ra = 2.76 µm. However, the groove width was larger than the wheel thickness due to the runout of the wheel. Additionally, the moderate elasticity and durability of the tool suggest that it might extend tool life by avoiding the crushing of abrasive grains.

Heat generation is a critical issue in grinding. If the grinding point generates significant heat, dimensional and shape accuracy may decrease due to thermal deformation, and the machined surface may deteriorate due to grinding burn. Therefore, monitoring the temperature during grinding is important to obtain ideal machining results. In this research, we develop a new method to measure the grinding surface and grinding wheel surface temperature during in-process machining. The proposed method measures the temperature of the grinding surface through small holes in a rotating grinding wheel. Using this method, we measured the temperature of the grinding surface during the dry grinding of carbon fiber reinforced plastics (CFRP). Temperature of the grinding surface was measured every 1/4 rotation of the grinding wheel at any depth of cut, assuming precision grinding, rough grinding, and high-efficiency grinding. The measurement value changed depending on the temperature measurement position of the infrared thermometer from numerical analysis of the grinding surface temperature. We also found that when the cut depth was small, the temperature, including the surface of the workpiece before machining, was measured at a specific temperature measurement position. The newly developed temperature measurement method was capable of in-process measurement of the grinding surface temperature and of detecting temperature rise when the grinding wheel was clogged.

(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) We have studied the kinetics and mechanism of particle nucleation in the emulsion polymerization of vinyl pivalate (VPi) under a wide variety of conditions. Quantitative comparisons between the theoretical and experimental estimations of the average number of radicals per polymer particle, ... as a function of the amounts of surfactant were performed. The relationship between ... and the parameter α^sub w^, the ratio of radical production in the aqueous phase to termination per particle, can be explained by assuming that chain-transferred monomer radicals escape from the particle. We studied the influence of the chain transfer agents (CTA), namely, n-dibutyl disulfide, t-dibutyl disulfide and l-cysteine in the emulsion polymerization. The addition of a CTA had a strong influence on the resulting degree of polymerization. The experimental results can be accounted on the basis of a kinetic analysis of the chain transfer reaction, assuming an increase of the rate of escape of chain-transferred radicals from the polymer particle.[PUBLICATION ABSTRACT]

We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes.

In clinical use, irinotecan hydrochloride (CPT‐11; 7‐ethyl‐10‐[4‐(piperidmo)‐l‐piperidino]carbonyl‐oxycamptothecin), a novel antitumor agent, causes a relatively high incidence of severe forms of diarrhea. We investigated whether baicalin, an inhibitor of β‐glucuronidase, which deconjugates the glucuronide of the active metabolite of CPT‐11, SN‐38 (7‐ethyl‐10‐hydorxycamptothecin), and Japanese herbal medicines (Kampo medicines) which contain baicalin can ameliorate CPT‐11‐induced intestinal toxicity in rats. CPT‐11 (60 mg/kg i.v. once daily for 4 consecutive days) induced intestinal toxicity characterized by diarrhea, loss of body weight, anorexia and disruption of intestinal epithelium. Treatment with baicalin (25 mg/kg p.o. twice daily) or Kampo medicines (TJ‐14 and TJ‐114; 1 g/kg p.o. twice daily) from the day before to 4 or 10 days after the start of CPT‐11 administration resulted in significantly decreased weight loss, improved anorexia and a delayed onset of diarrheal symptoms. Histological examination revealed that Kampo medicine‐treated animals had less damage to the intestinal epithelium and that damage was repaired more rapidly than in control rats. These results suggest that the prophylactic use of Kampo medicines (TJ‐14 and TJ‐114) may be of value against CPT‐11‐induced intestinal toxicity.

Targeting quantitative data in repeated-dose toxicity studies using rodents, a method for detecting an outlier and a selection problem between parametric and nonparametric approaches, based on actual toxicity data, was investigated. The consistency between the judgments of veteran toxicologists and several statistical methods (skewness, kurtosis, and the studentized residual) to detect an outlier was evaluated. The studentized residual had the highest consistency with the judgments of toxicologists and was the most effective method for detecting an outlier. The performance of the parametric (regression) method and the nonparametric method (Jonckheere test) for detecting dose-dependency was evaluated. Parametric and nonparametric approaches had a different result when outliers existed. Parametric methods are sensitive to the presence of outliers and they lose statistical power. In contrast, nonparametric approaches are robust to outliers. The identification of extreme individual measures is, however, a different objective for safety studies versus the detection of dose-dependency, and it may require different methods. Detecting an outlier, and investigating its impact on statistical analysis and biological interpretation, is very important and requires the use of appropriate methods.

A study was planned which evaluated the consistency between the judgments of toxicologists and well-established statistical methods to detect dose-dependency in repeated toxicity studies. Eighteen bits of repeated toxicity study data for both male and female rats were collected, which included hematology, blood chemistry, and organ weight (absolute and relative) data, totaling 2,001 items. Three or four toxicologists who had more than 10 years of experience judged dose-dependency and change at each dose for each item. The consistency between statistical methods and toxicologists was not as high as was expected. One of the major sources of this inconsistency resulted from the large amount of variation in the recognition among toxicologists. The recognition was qualitatively different, for instance, when there was a difference only between the highest dose and the control group, even if it was very evident, some toxicologists did not regard it as a dose-dependent relationship. It was shown that the consistency of change at each dose was moderately high. It is also noted that toxicologists tend to judge more conservatively than statistical tests at the 5% significance level. Considering the result of this study, a maximum contrast method is recommended to examine the dose-response shape, while avoiding the multiplicity of statistical tests.

SN-38, a metabolite of irinotecan hydrochloride (CPT-11), is considered to play a key role in the development of diarrhea as well as in the antitumor activity of CPT-11. We have previously found that the inhibition of beta-glucuronidase, which hydrolyzes detoxified SN-38 (SN-38 glucuronide) to reform SN-38, in the lumen by eliminating the intestinal microflora with antibiotics, markedly ameliorates the intestinal toxicity of CPT-11 in rats. In this study we compared the disposition of CPT-11 and its metabolites in rats treated with and without antibiotics. Rats were given drinking water containing 1 mg/ml penicillin and 2 mg/ml streptomycin from 5 days before the administration of CPT-11 (60 mg/kg i.v.) and throughout the experiment. CPT-11, SN-38 glucuronide and SN-38 concentrations in the blood, intestinal tissues and intestinal luminal contents were determined by HPLC. Antibiotics had little or no effect on the pharmacokinetics of CPT-11, SN-38 glucuronide or SN-38 in the blood, or in the tissues or contents of the small intestine, which has less beta-glucuronidase activity in its luminal contents. In contrast, antibiotics markedly reduced the AUC1-24 h of SN-38 (by about 85%) in the large intestine tissue without changing that of CPT-11, and this was accompanied by a complete inhibition of the deconjugation of SN-38 glucuronide in the luminal contents. These results suggest that SN-38, which results from the hydrolysis of SN-38 glucuronide by beta-glucuronidase in the intestinal microflora, contributes considerably to the distribution of SN-38 in the large intestine tissue, and that inhibition of the beta-glucuronidase activity by antibiotics results in decreased accumulation of SN-38 in the large intestine.

We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes.