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1.
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
4.
T Omland T Aarsland A Aakvaag RT Lie K Dickstein 《Canadian Metallurgical Quarterly》1993,72(3):255-259
Case reports from the United Kingdom (UK) in 1989 have suggested that the introduction of human insulin in 1985 was associated with an increased risk of sudden death in insulin-treated diabetic patients. If human insulin increases the risk of sudden death, the number of these should have increased during the period where human insulin was introduced. We therefore identified all cases of sudden death in Denmark in younger insulin-treated diabetic patients, age at death below 50 years. During this period the consumption of human insulin went from 0.2% to 70% of the total consumption in Denmark. The total number of cases fulfilling the inclusion criteria was 226, and the annual number of sudden deaths did not change during the study period (p = 0.14). The number of deaths due to hypoglycaemia and cases with unexplained cause of death also remained constant (test for trend: p = 0.44). Chronic alcohol abuse or acute alcohol intoxication was found in 50% of the 135 patients dying from hypoglycaemia, ketoacidosis or unknown cause of death (including found dead in bed), while this was the case in only 16% of the remaining 91 cases dying from other natural causes. We conclude that introduction of human insulin in Denmark was not followed by an increase in sudden deaths among younger insulin-treated diabetic patients. 相似文献
5.
ES Lie A Heyden MK Johannesen M Boysen P Brandtzaeg 《Canadian Metallurgical Quarterly》1996,116(4):627-632
The frequency of human papillomavirus (HPV) in laryngeal papillomas varies largely among different studies. DNA in situ hybridization (ISH) has been the most widely used method for detection of HPV. The aim of this study was to compare the reproducibility and sensitivity of ISH with polymerase chain reaction (PCR) in 35 specimens of laryngeal papillomas routinely fixed in buffered or unbuffered formalin. Out of 12 specimens fixed in buffered formalin, 10 were positive for HPV 6/11 using ISH. The procedure was repeated three times and three specimens were positive only twice. Nine biopsies were positive for HPV using PCR with consensus primers (My 09/11) on dewaxed tissue without extracting DNA. In three repeated PCRs, the results were inconsistent in three samples. After DNA extraction, all 12 samples were positive with PCR. Of the 23 specimens fixed in unbuffered formalin, 14 were HPV-positive with ISH, while only one was positive with PCR. We concluded that PCR with My 09/11 consensus primers is a highly sensitive method for detection of HPV in laryngeal papillomas fixed in buffered formalin, but useless for samples fixed in unbuffered formalin. When DNA was extracted from the former type of fixed tissue, the results were highly reproducible. In contrast to PCR, ISH appeared to be less influenced by fixation procedure, but it was not as reproducible and sensitive as PCR. Negative results did not necessarily mean absence of HPV. 相似文献
6.
A synthesis procedure for generating current conveyor active filters is presented, and a novel network which realises the general 2nd-order voltage transfer function is given.<> 相似文献
7.
Excel在大学物理实验中的应用 总被引:1,自引:0,他引:1
利用Excel的强大功能,对实验数据进行处理、分析,对实验过程及实验结果的监控。 相似文献
8.
L Fr?yland DK Asiedu H Vaagenes A Garras O Lie GK Totland RK Berge 《Canadian Metallurgical Quarterly》1995,36(12):2529-2540
The mechanism behind the hypolipidemic effect of tetradecylthioacetic acid (CMTTD, a non-beta-oxidizable 3-thia fatty acid) was studied in hamsters fed a high cholesterol diet (2%), which resulted in hyperlipidemia. Treating hyperlipidemic hamsters with CMTTD resulted in a progressive hypocholesterolemic and hypotriacylglycerolemic effect. Decreased plasma cholesterol was followed by a 39% and 30% reduction in VLDL-cholesterol and LDL-cholesterol, respectively. In contrast, the HDL-cholesterol content was not affected, thus decreasing the VLDL-cholesterol/HDL-cholesterol and LDL-cholesterol/HDL-cholesterol ratios. 3-Hydroxy-3-methylglutaryl- (HMG) CoA reductase activity and its mRNA level were unchanged after CMTTD administration. Also, the LDL receptor and LDL receptor-related protein (LRP-4) mRNAs were unchanged. The decrease in plasma triacylglycerol was accompanied by a 45% and 56% reduction in VLDL-triacylglycerol and LDL-triacylglycerol, respectively. The hypolipidemic effect of CMTTD was followed by a 1.4-fold increase in mitochondrial fatty acid oxidation and a 2.3-fold increase in peroxisomal fatty acid oxidation. CMTTD treatment led to an accumulation of dihomo-gamma-linolenic acid (20:3n-6) in liver, plasma, very low density lipoprotein, and heart. Noteworthy, CMTTD accumulated more in the heart, plasma, and VLDL particles compared to the liver, and in the VLDL particle alpha-linolenic acid (18:3n-3) decreased whereas eicosatetraenoic acid (20:4n-3) increased. In addition, linoleic acid (18:2n-6) and the total amount of polyunsaturated fatty acids decreased, the latter mainly due to a decrease in n-6 fatty acids. The present data show that CMTTD was detected in plasma and incorporated into VLDL, liver, and heart. The relative incorporation (mol%) of CMTTD was heart > VLDL > liver. In conclusion, CMTTD causes both a hypocholesterolemic and hypotriacylglycerolemic effect in hyperlipidemic hamsters. 相似文献
9.
Tek Bahadur Gurung 《Lakes & Reservoirs: Research and Management》2007,12(4):237-246
Lake Rupa is a small, subtropical, shallow lake with a surface area of 100 ha situated 600 m a.s.l. in Central Himalaya, Nepal. This degraded lake was studied between 2000 and 2006, with the goal of determining whether or not it could be restored by a community‐based cooperative of local people living in its catchment. Main threats to the lake, its aquatic life and its very existence include encroachment by excessive aquatic vegetation, sedimentation, and low in‐lake concentrations of dissolved oxygen (DO). Small lakes (≤ 500 ha) are relatively prone to the process of ‘succession and climax’, although they also can be of social, environmental and ecological importance. Thus, their disappearance could spark social chaos and disorder in areas already having to cope with other rapid environmental changes. This means that credible mechanisms for revitalizing or protecting small lakes are an important goal. Accordingly, a lake cooperative of 329 households living in close vicinity to Lake Rupa was formed in 2002, by prioritizing traditional fishers, women and other deprived community members with the goals of respecting the citizenry and equity. Following the cooperative's campaigns directed at weed removal and fish stocking, encroachment of vegetation on the lake margins was halted, its aquatic weeds became under control, and its fisheries improved. In addition to the cooperative's restoration activities, several water quality parameters, including water transparency and DO and chlorophyll‐a concentrations, were monitored on a monthly basis. The measured water transparency was inconsistent, exhibiting large variations between 2000 and 2003. Relatively low, but consistent, values, however, were measured after 2004. The results imply that the removal of weeds, and sufficient nutrients and solar radiation are subsequently available to the lake's phytoplankton communities. Supporting this notion is that the chlorophyll‐a concentration spiked to 205 µg L−1 in November 2006, the water transparency became consistent, and the DO concentration increased to >3.8 mg L−1 during the critical months (March–May) after 2004. These water quality indicators indicated improvement in the degraded Lake Rupa, suggesting that the establishment of cooperatives such as that highlighted in this study could be a powerful and sustainable mechanism for restoring degraded lakes in similar socioeconomic settings by maintaining equity, by connecting communities with their resources, and by facilitating integrity, equity, citizenry and social justice. 相似文献
10.
The association of antiphospholipid antibodies with unexplained thrombo-occlusive vascular disease is well known but often remains unrecognized. The most well-studied clinical manifestation is venous thrombosis, but arterial occlusive disease involving multiple sites is also well documented. Twenty-six cases of thrombo-occlusive disease were observed in 22 patients over a 3-year period. Magnetic resonance imaging and angiography were used to make the diagnoses. None of the patients who underwent angiography or venography developed thrombolytic disease related to the puncture site. This group of patients with antiphospholipid antibody syndrome had a wide distribution of arterial and venous thrombotic disease. Radiologists should consider antiphospholipid antibody syndrome in the differential diagnosis when evaluating thrombo-occlusive vascular disease that is unexpected or occurs without risk factors. Knowledge of antiphospholipid antibody status has important implications for prognosis and therapy. 相似文献