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21.
Optimization of groove dimensions in herringbone-grooved journal bearings is discussed in this paper with aims to design precision spindles with improved run-out characteristics. An evaluation index to represent the magnitude of the amplitude of repeatable run-out is firstly introduced and the groove design parameters are theoretically discussed to minimize the index value with taking the stable operation condition of the bearing into account. The comprehensive parameter research reveals a guideline for the design of the groove configuration for good run-out characteristics. Experiments with a shaft with grooves designed along the proposed guideline show that the amplitude of repeatable run-out reduces to about half of that of a bearing with currently designed groove configurations, thus confirming validity of the above guideline.  相似文献   
22.
The profile of volatile organic compounds (VOCs) released from Glomerella cingulata using solid phase microextraction (SPME) with different fibers, Polydimethylsiloxane (PDMS), Polydimethylsiloxane/Divinylbenzene (PDMS/DVB), Carboxen/Polydimethylsiloxane (CAR/PDMS) and Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS), was investigated. C4-C6 aliphatic alcohols were the predominant fraction of VOCs isolated by CAR/PDMS fiber. Sesquiterpene hydrocarbons represented 20.3% of VOCs isolated by PDMS fiber. During the growth phase, Ochracin was produced in the large majority of VOCs. 3-Methylbutanol and phenylethyl alcohol were found in the log phase of it. Alcohols were found in cultures of higher age, while sesquiterpenes were found to be characteristic of initial growth stage of G. cingulata.  相似文献   
23.
Tris(1,3-dichloro-2-propyl) phosphate (TDCPP), a flame retardant, is regarded as a potentially toxic and persistent environmental contaminant. We previously isolated a TDCPP-degrading bacterium, Sphingobium sp. strain TCM1, which, however, produced a toxic metabolite: 1,3-dichloro-2-propanol (1,3-DCP). This study was undertaken to develop a technique for complete TDCPP detoxification using strain TCM1 with a 1,3-DCP-degrading bacterium, Arthrobacter sp. strain PY1. For efficient detoxification, we designed a resting cell system and examined the effect of freezing and lyophilization treatments for preparation of their resting cells. Results show that treatments had no marked adverse effect on their activities. The TDCPP dephosphorylation by TCM1 resting cells was optimal at 30°C and pH 8.5. Also, 1,3-DCP dehalogenation by strain PY1 resting cells was optimal at 35°C and pH 9.5. Under those respective conditions, the activities were 2.48 μmol h− 1·OD660− 1 for TDCPP and 0.95 μmol h− 1·OD660− 1 for 1,3-DCP. Based on these results, we set the reaction temperature to 30°C and pH to 9.0. Then we examined the detoxification of 50 μM TDCPP using mixed resting cells at a final OD660 of 0.05 for strain TCM1 and 0.2 for strain PY1. In these conditions, TDCPP was eliminated after 1 h, but some of the resulting 1,3-DCP remained at a constant level. The increase in strain PY1 cells to a final OD660 of 4.0 decreased the TDCPP dephosphorylation rate of strain TCM1 cells but achieved complete detoxification of TDCPP during 12 h of reaction.  相似文献   
24.
Trypsins from the pyloric ceca of jacopever (Sebastes schlegelii), TR-J, and elkhorn sculpin (Alcichthys alcicornis), TR-E, were purified by gel filtration on Sephacryl S-200 and Sephadex G-50. The molecular weights of TR-J and TR-E were estimated to be 24,000 Da by sodium dodecyl sulfate–polyacrylamide gel electrophoresis. TR-J and TR-E revealed optimum temperatures of 60 and 50 °C, respectively, and showed the same optimum pH (pH 8.0) for hydrolysis of N-p-tosyl-l-arginine methyl ester. TR-J and TR-E were unstable at above 50 and 40 °C, respectively, and were more stable at alkaline pH than at acidic pH. Thermal stabilities of TR-J and TR-E were highly calcium dependent. These purified trypsin enzymes were inhibited by serine protease inhibitors, such as TLCK and soybean trypsin inhibitor. The N-terminal amino acid sequences of TR-J and TR-E were also investigated. The N-terminal amino acid sequences of TR-J, IVGGYECKPYSQPHQVSLNS, and TR-E, IVGGYECTPHSQAHQVSLNS, were found, and these sequences showed highly homology to other fish trypsins.  相似文献   
25.
Triple-negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes. Recently, the activation of NF-κB, which is involved in the growth and survival of malignant tumors, has been demonstrated in TNBC, suggesting that NF-κB may serve as a new therapeutic target. In the present study, we examined whether dimethyl fumarate (DMF), an NF-κB inhibitor, induces apoptosis in TNBC cells and enhances the apoptosis-inducing effect of paclitaxel and adriamycin. Cell survival was analyzed by the trypan blue assay and apoptosis assay. Protein detection was examined by immunoblotting. The activation of NF-κB p65 was correlated with poor prognosis in patients with TNBC. DMF induced apoptosis in MDA-MB-231 and BT-549 cells at concentrations that were non-cytotoxic to the normal mammary cell line MCF-10A. Furthermore, DMF inhibited NF-κB nuclear translocation and Survivin, XIAP, Bcl-xL, and Bcl-2 expression in MDA-MB-231 and BT-549 cells. Moreover, DMF enhanced the apoptosis-inducing effect of paclitaxel and adriamycin in MDA-MB-231 cells. These findings suggest that DMF may be an effective therapeutic agent for the treatment of TNBC, in which NF-κB is constitutively active. DMF may also be useful as an adjuvant therapy to conventional anticancer drugs.  相似文献   
26.
27.
Usually a structured FORTRAN program is transformed into a standard FORTRAN program by means of a one-pass preprocessor. In this case, several problems are caused by the many redundant continue and goto statements that a preprocessor generates. These problems include: (i) the generated FORTRAN program is not easy to read; (ii) the size of files to store the related programs becomes large; (iii) the total time increases for executing both the FORTRAN compiler and the output program itself. This paper presents a new scheme for constructing a one-pass preprocessor that generates the optimized FORTRAN code by suppressing the redundant statements. By employing this scheme we have constructed our own preprocessors for Westran (one of the Structured FORTRAN languages) and Ratfor and measured these against the traditional preprocessors for the Westran and Ratfor languages. One of the results is as follows. The total time for users, namely ‘preprocessing time + FORTRAN compiling time’ is rather less than the traditional ones. This is due to the fact that to suppress the input/output of the redundant statements from/to files contributes to the decreasing of both preprocessing and compiling times, and this compensates completely the time-overhead of the optimization process.  相似文献   
28.
An 8 Mb embedded DRAM has been developed. The salient feature of this embedded DRAM is page fault tolerance. Accessing across different pages can be performed using a minimum column cycle. This feature is achieved by placing a data latch and a transfer gate between the bit line sense amplifier and the column select gate. This DRAM can be reconfigured as separated 2 Mb units when it is embedded as a macro cell of an ASIC library  相似文献   
29.
A novel method is presented for calibrating a six-port reflectometer using only one sliding load of unknown reflection coefficient and one short as a calibration standard. The calibration procedure is derived from the fact that the Fourier coefficients of the periodic port power ratios corresponding to the sliding load positions are closely related to the six-port system parameters. The unknown reflection coefficient of the sliding load as well as the eleven system parameters at each frequency is determined in the procedure. The validity and utility of the proposed method are confirmed by experiments over the frequency range 8.5-12.0 GHz in 0.5 GHz steps with a rectangular waveguide sliding load and a polished metal standard short  相似文献   
30.
Cancer-free tissues from various anatomical subsites in the head and neck were examined by the polymerase chain reaction (PCR) for the incidence of human papillomavirus (HPV) types 16 and 18. We detected HPV-16 DNA in 9 of 103 samples (8.7%), including specimens from the paranasal sinuses, tonsil, hypopharynx and larynx. However, no HPV-16/18 DNA was detected by Southern hybridization in these 9 samples. The significance of the presence of HPV-16 DNA in non-cancer tissues is still unknown, but PCR detection only of high-risk HPV DNA in head and neck cancer should be evaluated cautiously because of its ubiquity in this region.  相似文献   
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