Power transformers are usually very reliable and durable components. Their performance is often taken for granted and they are overlooked until a problem occurs. Unfortunately, when a fault occurs in ...a transformer, it can develop catastrophically and failures are usually very expensive if not uneconomic to repair. As the largest power utility in Hong Kong, CLP Power proactively explore the opportunity and manage the threat in order to provide a highly reliable supply of electricity and excellent customer services to over 6 million people in Kowloon, the New Territories, Lantau and most of the outlaying islands of Hong Kong. (8 pages)
We report a new CMOS-compatible salicidation process to achieve sub-0.1 eV effective Schottky barrier (SB) height for NiSi/n-Si, one of the lowest values reported-to-date, and its device integration ...for contact resistance reduction in n-FETs. A thin solid Antimony (Sb) layer is inserted beneath Ni prior to S/D silicidation, acting as a large source of n-type dopants. After silicidation, a very high concentration of Sb is incorporated at the NiSi/Si interface. This solid Sb segregation (SSbS) process reduces the effective SB height and parasitic series resistance. The SSbS process leads to enhanced n-FET performance without degradation in off-state leakage.
The Internet has led to the formation of a global information infrastructure. To explore a web site, a site map would be useful as a short cut for a user to locate for the target information in a ...structured and efficient manner, rather than drilling into the web site following hyperlinks, reading possibly irrelevant information. Useless information impacts a mobile web environment, where mobile clients are only connected with unreliable wireless channels of limited bandwidth. Structured web page organization at the web server proxy is an important issue to resolve to provide efficient browsing experience for web clients, while minimizing the browsing of unrelated pages or sites. In this paper, we adopt the Document Information Extraction mechanism to construct a document cluster dynamically and intelligently with respect to a requested root web page. The document cluster works like a dynamic site map, spanning across several web sites. The clusters are generated and stored in XML format at proxy server so that it can potentially benefit a large number of mobile clients. Clients process the XML clusters and transform them to be visualized through VRML or DOM. For VRML, a transformer is built at the client-side to support a three-dimensional modeling view. For DOM, JavaScript is used for accessing the parsed XML data to produce a two-dimensional tree output.
Prolonged ethanol administration has been reported to cause defects in cardiac performance and abnormal cardiac lipid contents. However, little is known regarding the short-term administration of ...ethanol to the perfused heart and its effect on cardiac phospholipid metabolism. In this study, the isolated Langendorff heart perfusion was used as a model to study the effects of ethanol and a combination of ethanol and vitamin E (DL-alpha-tocopherol) on phospholipid metabolism. When perfused with 1% ethanol for 4 h, the major cardiac phospholipids were not altered but a 60% increase in lysophosphatidylcholine level was observed. Studies on the lysophosphatidylcholine metabolic enzymes revealed that phospholipase A (both phospholipase A1 and A2) activity was enhanced in the ethanol-perfused heart, but lysophospholipase and acyltransferase activities were unaffected by ethanol treatment. When the heart was perfused with 1% ethanol in the presence of 50-100 microM vitamin E, the ethanol-induced lysophosphatidylcholine accumulation was completely abolished. This was largely attributed to the attenuation of phospholipase A activities by vitamin E. In order to delineate the opposing effects of ethanol and vitamin E on phospholipid metabolism in the heart, phospholipase A activities in the subcellular fractions were determined in the presence of 0.5-2.0% ethanol or a combination of 1% ethanol and 0-100 microM vitamin E. Ethanol alone exhibited a biphasic effect on phospholipase A activity with maximum stimulation of enzyme activities at 1% concentration. When phospholipase A was assayed in 1% ethanol and vitamin E (25-100 microM), its activity was inhibited by vitamin E in a dose-dependent manner. The mechanism by which ethanol enhanced phospholipase A activities was further investigated with a partially purified enzyme from the rat heart cytosol. Kinetic studies with different concentrations of phosphatidylcholine revealed that at low substrate concentrations, ethanol was inhibitory to the reaction, whereas at high substrate concentrations, the reaction was enhanced by ethanol. Vitamin E (50 microM) completely abolished the ethanol-induced enhancement of enzyme activity in a noncompetitive manner. Since lysophosphatidylcholine is cytolytic at high concentration and its accumulation in the heart has been postulated as a biochemical cause of cardiac dysfunction, the level of the lysolipid in the heart must be under rigid control. Our result suggest that the modulation of cardiac phospholipase A activity is an important mechanism for the the regulation of lysophosphatidylcholine levels in the rat heart.
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