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Lie‐Fern Hsu 《Quality and Reliability Engineering International》2007,23(2):269-272
He and Grigoryan (Quality and Reliability Engineering International 2002; 18 :343–355) formulated the design of a double‐sampling (DS) s control chart as an optimization problem and solved it with a genetic algorithm. They concluded that the DS s control charts can be a more economically preferable alternative in detecting small shifts than traditional s control charts. We explain that, since they only considered the average sample size when the process is in control, their conclusion is questionable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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The Analysis Committee of the European Brewery Convention is aware that the Friabilimeter sometimes is used on samples that do not comply with the field of application. The precision of the method is also overlooked by some users. The field of application, precision of the method as well as the need for frequent testing of the instrument is therefore stressed in more detail than in the earlier published method by the EBC Analysis Committee. 相似文献
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INTRODUCTIONS: Cochlear implants are used for the rehabilitation of bilaterally deaf patients. Due to the improvements in speech processing they might be also useful for patients with residual hearing and some speech understanding. METHODS: Pre- and postoperative speech understanding scores in 26 patients receiving implants were evaluated in a retrospective study. RESULTS: The preoperative pure-tone threshold in the implanted ear was between 80 and 115 dB in the frequency range of 500 to 2000 Hz. On the contralateral side the mean threshold was 10 dB better. The mean score for the number test was 11.3%, for the monosyllables below 5%. Postoperatively speech understanding improved significantly up to 97% for numbers and 48% for monosyllables (tested with the Freiburger Speech Test). Cochlear implantation also benefits patients with residual hearing and some speech understanding with hearing aids under optimum conditions. The speech understanding scores must be below certain limits. General selection criteria cannot yet be specified. The individual decision must be based upon several criteria, especially the speech understanding scores in quiet and noise under optimum conditions. A prospective study is needed to develop generally applicable criteria. 相似文献
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Cytoplasmic aggregation is an early resistance-associated event that is observed in potato tissues either after penetration of an incompatible race of Phytophthora infestans, the potato late blight fungus, or after treatment with hyphal wall components (HWC) prepared from P. infestans. In potato cells in suspension culture, the number of cells with cytoplasmic aggregation increased upon treatment with HWC, but such an increase was suppressed by treatment with cytochalasin D prior to treatment with HWC. This result suggested that cytoplasmic aggregation in cultured potato cells might be connected with the association of actin filaments. To identify the molecular basis of cytoplasmic aggregation, we purified actin and actin-related proteins by affinity chromatography on a column of immobilized DNase I from cultured potato cells and isolated proteins of 43 kDa, 32 kDa and 22 kDa. Analysis of the amino-terminal amino acid sequences indicated that the 43 kDa, 32 kDa and 22 kDa proteins were potato actin, basic chitinase and osmotin-like protein, respectively. This conclusion was supported by the results of Western blotting analysis of the 43 kDa and 32 kDa proteins with antibodies against actin and basic chitinase. Binding analysis with actin coupled to actin-specific antibodies and biotinylated actin suggested that the 32 kDa and 22 kDa proteins had actin-binding activity. In addition, examination of biomolecular interactions using an optical biosensor confirmed the binding of chitinase to actin. These results imply the possibility that basic chitinase and osmotin-like protein might be involved in cytoplasmic aggregation, hereby participating. In the potato cell's defense against attack by pathogen. 相似文献
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A theoretical model is presented by which a true expression of pregnancy rate resulting from stimulated cycles can be calculated. This includes the transfer of both fresh and cryopreserved embryos. It is concluded that the total reproductive potential of a single cycle of stimulation can only be evaluated by including pregnancies arising from all fresh and frozen embryo transfers resulting from that cycle. 相似文献
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Scanning electron microscopy was used to study the effect of cyclophosphamide (Cy) on molar development in 18 Sprague-Dawley rats from 15 to 48 days of age after birth. Doses of 30 mg/kg body weight of Cy dissolved in 1 ml 0.9% NaCl were given to the rats at 10 and 13 days of age. Eighteen control rats had injections of 1 ml 0.9% NaCl at the same ages. The most obvious changes in the experimental teeth were found in the developing roots of the first and second molars and in both the crown and roots of the third molar. The roots of the first and second molars were short and showed apical closure in the experimental rats. In addition to the disturbances in crown and root formation, the third molars were also significantly reduced in total size as compared with the third molars in the control rats. 相似文献