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1.
This article sets out to investigate the critical factors of Knowledge Management (KM) which are considered to have an impact on the performance of Chinese information and communication technology (ICT) firms. This study confirms that the cultural environment of an enterprise is central to its success in the context of China. It shows that a collaborated, trusted, and learning environment within ICT firms will have a positive impact on their KM performance.  相似文献   
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Curved Planar Reformation (CPR) has proved to be a practical and widely used tool for the visualization of curved tubular structures within the human body. It has been useful in medical procedures involving the examination of blood vessels and the spine. However, it is more difficult to use it for large, tubular, structures such as the trachea and the colon because abnormalities may be smaller relative to the size of the structure and may not have such distinct density and shape characteristics. Our new approach improves on this situation by using volume rendering for hollow regions and standard CPR for the surrounding tissue. This effectively combines gray scale contextual information with detailed color information from the area of interest. The approach is successfully used with each of the standard CPR types and the resulting images are promising as an alternative to virtual endoscopy. Because the CPR and the volume rendering are tightly coupled, the projection method used has a significant effect on properties of the volume renderer, such as distortion and isometry. We describe and compare the different CPR projection methods and how they affect the volume rendering process. A version of the algorithm is also presented which makes use of importance driven techniques; this ensures the users attention is always focused on the area of interest and also improves the speed of the algorithm.  相似文献   
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31P-Nuclear magnetic resonance (NMR) spectroscopy was employed to detect and quantify free glycerol in virgin olive oils originating from various regions of Greece. This analytical method was based on the derivatization of the hydroxyl groups of glycerol with the tagging reagent 2-chloro-4,4,5,5-tetramethyldioxaphospholane, and identification of the phosphitylated compound on the basis of 31P chemical shifts. Quantification of glycerol in olive oils was accomplished by integration of the appropriate signals in the 31P NMR spectrum and the use of the phosphitylated cyclohexanol as internal standard. A linear correlation was observed between the glycerol content and 1,3-diacylglycerols and free acidity indicating that glycerol is the final product of the partial hydrolysis of triacylglycerols.  相似文献   
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Normal women produce small amounts of active androgens. When androgen levels are elevated, such as for example in the polycystic ovary syndrome, this is followed by the development of male physical characteristics and muscle mass, structure and function as well as android adipose tissue distribution and function. Psychological features and stress reactions also seem similar to those of men. Such women have an increased risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular disease. Recent data have shown that these physical, and psychological characteristics, as well as risk of ill health, are also found in the population of women selected at random. Women in the lowest quintiles of levels of sex-hormone-binding globulin--an indicator inversely related to active androgens--are at risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular mortality. The mechanism probably includes muscular insulin resistance, following a relative androgen excess. It is thus apparent that androgens, even within the highest levels of the nonselected population of women, are powerful predictors of serious disease development. The population at risk might be as large as about 20% of middle-aged women. This is an area of female disease risk which requires more attention in screening and intervention procedures.  相似文献   
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Linear polymers of silicone gums (polysiloxanes) have many attributes that make them attractive for lithographic applications, such as oxidative and thermal stability, good adhesion properties, solubility in common solvents, and resistance to etching in an oxygen plasma. When polysiloxanes are used as the top imaging layer (~2000Å) in a two-layer resist system, the developed negative siloxane images act as a high resolution etch mask for the oxygen plasma etching of the bottom planarizing polymer layer. Commercially available polysiloxanes have been evaluated for their deep UV sensitivity at 2537Å, and have been found to have very high resolution capabilities (~0.5μ) and high contrast (γ = 4). The negative images do not swell in the developer, and the line width is therefore independent of development time. The combination of high resolution, sensitivity, and ease of processing make this a simple multilayer system for deep UV and e-beam applications.  相似文献   
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This study examined the correlates of symptoms of depressed mood among adolescents in 2 dramatically different cultures (n?=?502 in Tianjin, People's Republic of China; n?=?201 in greater Los Angeles). Gender, stressful life events, perceived parental warmth, and conflict with parents were associated in the expected direction with depressive symptoms in each cultural setting. As predicted, regression analyses showed that the quality of family relationships and grades in school had significantly stronger associations with depressive symptoms among Chinese youths than among U.S. youths, whereas gender differences in depressive symptoms were greater among the U.S. youths. Peer warmth moderated the effects of particular risk factors for depressive symptoms in each cultural setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We have investigated if interferon-gamma (IFN-gamma) treatment of human K562 tumor cells, which upregulates the expression of MHC class I antigens (MHC-I), simultaneously would influence insulin binding. Treatment of K562 cells with recombinant human IFN-gamma for 48 h caused a significant increase of insulin binding at 37 degrees C. Recombinant human tumor necrosis factor-alpha (TNF-alpha) alone had no effect but acted synergistically with IFN-gamma, leading to a two-fold increase of insulin binding. No change in affinity, number of binding sites or cell surface expression of insulin receptors (IR) after IFN-gamma treatment could be detected. The increased insulin binding observed at 37 degrees C was not seen at 4 degrees C, suggesting alteration of insulin internalization. The dose-response curve, as well as the time curve, for the increase in insulin binding after IFN-gamma treatment correlated with enhanced cell surface expression of MHC-I antigens. However, the correlation was not absolute. Our results show that IFN-gamma treatment alone or together with TNF-alpha, can alter the insulin binding to K562 cells without changing the expression or affinity of the IR. This correlates with the effect of IFN-gamma on MHC-I expression. These results support the findings that MHC-I molecules associate and interact with the IR at the cell surface.  相似文献   
10.
A low-temperature, all-vacuum process combined with electron-beam lithography suitable for single-level masking devices using 2-μm diameter amorphous bubble films has been developed. A test vehicle which uses 0.75-μm wide chevrons and 1-μm wide T.I bars in an 8,000- bit chip configuration, resulting in an areal density of 1×107bits/in2, was used. Important process features are found to be: (1) laminated NiFe films to obtain low Hcand high magneto-resistive effect when deposited at low substrate temperature, (2) maintenance of low surface temperature during metallization to preserve the integrity of exposed and developed electron-beam resist pattern, and (3) proper resist profile for ease of the lift-off process. Excellent bubble device operating characteristics have been obtained as a result of uniformity in materials and structure resulting from careful control of fabrication parameters.  相似文献   
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