Copper and iron interactions with angiotensin-converting enzyme inhibitors. A study by fast-atom bombardment tandem mass spectrometry

Fast atom bombardment, combined with high-energy collision-induced tandem mass spectrometry, has been used to investigate gas-phase metal-ion interactions with captopril, enalaprilat and lisinopril, all angiotensin-converting enzyme inhibitors.Suggestions for the location of metal-binding sites are presented. For captopril, metal binding occurs most likely at both the sulphur and the nitrogen atom. For enalaprilat and lisinopril, binding preferably occurs at the amine nitrogen. Copyright 1999 John Wiley & Sons, Ltd.     

An overview of Internet protocols

In a very short period of time, the Internet has risen from being viewed as a peculiarity of the defence and academic community of the late sixties to become a significant component of many of our working and home lives. The possible impact of this technology has the futurists talking of the collapse of national borders, the bypass of tax systems and traditional commerce and the emancipation of the individual from the clutches of government, corporations and the boundaries of culture, gender and physical constraints. Most users' experience of the Internet is through browser software and applications such as e-mail, World Wide Web, Newsgroups and media plug-ins. Beneath this glossy, graphical, multimedia world exists the architectural and protocol components which have enabled the Internet evolution to reach into so many parts of everday life in such a short time. The aim of this paper is to outline some of these components, their characteristics and limitations, and their ongoing development to address those limitations and add new capabilities. Even though an overview of Internet protocols is included in this paper, basic knowledge of Internet technology is assumed.     

医疗环境中的液压测量

正兼容液体介质的压力传感器通常可简化医疗系统的设计和降低其成本某些OEM医疗设备要求具备能在凝露或液体环境下使用的压力传感器。兼容液体介质的压力传感器,可免受液体侵害,且无需额外采取防护,减少了与此相关的设计复杂性和成本。为OEM医疗设备应用选择最佳     

Determination of loads applied perpendicularly to the outer boundary of a ring using coefficients of influence

A procedure is explained to determined the amount of several pairs of diametrical loads applied to the outside boundary of a ring when stresses at selected points of the inside or outside boundaries are known. Coefficients of influence are used, following an approach similar to the one presented in a previous paper. Examples of application are given and the possible increase in precision is shown when the number of points of measurements is larger than the number of loads to be determined.