Pacemakers research

Furthermore, pH determination has been used in other clinical research, both alone and in combination with other measurements. This research includes studies into the relationship between extracellular and intracellular pH in an ischemic heart [6, 7], the pH of airway lining fluid in respiratory disease [8], the study of pH as a marker for pyloric stenosis [9], malnutrition in alkalotic peritoneal dialysis patients [10], pH modulation of heterosexual HIV transmission [11, 12], and wound prevention and treatment [13], In addition, pH changes due to blood acidosis have been used to trigger and pace the ventricular rate of an implanted cardiac pacemaker [14], Research using pH measurements... 

Since plutonium is the actinide generating most concern at the moment this review will be concerned primarily with this element. However, in the event of the fast breeder reactors being introduced the behaviour of americium and curium will be emphasised. As neptunium is of no major concern in comparison to plutonium there has been little research conducted on its behaviour in the biosphere. This review will not discuss the behaviour of berkelium, californium, einsteinium, fermium, mendelevium, nobelium and lawrencium which are of no concern in the nuclear power programme although some of these actinides may be used in nuclear powered pacemakers. Occasionally other actinides, and some lanthanides, are referred to but merely to illustrate a particular fact of the actinides with greater clarity. 

Using print and electronic resources, research the work of Wilson Greatbatch, the inventor of the implantable pacemaker. What chemistry-related technological challenges did he face and overcome as he perfected his device ... 

The discovery of peripheral oscillators in mammals has raised the question of how the SCN master pacemaker synchronizes these subsidiary clocks. Current evidence suggests that feeding time is the dominant eitgeber for most peripheral oscillators. The molecular mechanisms involved in food-dependent phase resetting are not yet understood, and deciphering the signalHng pathways involved will probably require many additional years of intense genetic and biochemical research. 

Much of the recent research in solid state chemistry is related to the ionic conductivity properties of solids, and new electrochemical cells and devices are being developed that contain solid, instead of liquid, electrolytes. Solid-state batteries are potentially useful because they can perform over a wide temperature range, they have a long shelf life, it is possible to make them very small, and they are spill-proof We use batteries all the time—to start cars, in toys, watches, cardiac pacemakers, and so on. Increasingly we need lightweight, small but powerful batteries for a variety of uses such as computer memory chips, laptop computers, and mobile phones. Once a primary battery has discharged, the reaction cannot be reversed and it has to be thrown away, so there is also interest in solid electrolytes in the production of secondary or storage batteries, which are reversible because once the chemical reaction has taken place the reactant concentrations can be... 

The most welcome technical achievements in life science are the ones that enhance well-being or restore impaired or lost biological functions. Rehabilitation engineering is a research field that has devoted its full spectrum of efforts to compensate for malfunctions and disorders in human biological systems. This includes the development of devices for the rehabilitation of neural disorders which are termed neural prostheses. Neural prostheses directly interface with the central and peripheral nervous system. The most commonly known neural prosthesis is the cardiac pacemaker, which has existed for more than 30 years. A variety of other lesser known devices have been developed to partially restore neural functions in disabled people. 

The first pacemaker, the result of lor, arduous research, was used in a patient in 1958. The pacemaker device was not implanted, but its wire was connected to the patient s heart. The pacemaker itself was so large that it had to be carted around in a grocery store cart. While it was a sduHcn to the patient s arrhythmia, it was hardly practical. Fortunately, pacemakers were socn miniaturized. 

Another surgical intervention, widely used in Europe for more than a decade gained United States Food and Drug Administration in 2002. The procedure involves implanting a pacemaker-hke device to provide electrical stimulation to areas of the brain deprived of dopamine. Still more research... 

Lithium-ion batteries are compact and lightweight and have high energy density and long lifetimes, which make them useful in pacemakers like the Guidant Pulsar dual-chamber pacemaker pictured here with an eight-year lithium-oxide battery at left. (Leonard Lessin/Photo Researchers, Inc.)... 

The editors and authors, all internationally recognized experts in their area, succeeded in presenting the manifold itspects of template-controlled synthesis in a didactic way, making this methodology accessible to a broad readership of organic synthetic chemists. Well-selected. reliable key experimental protocols and an up-to-date reference list underline the practical approach of this valuable handbook. Being the first book of its kind, it will serve as a pacemaker and stimulate future research. 

The low penetrating radiation, long half-life, and high power density of Pu makes it ideal for special purpose power supplies ( 6.9.3). The main present use is in space research, and 30 kW power sources have been launched into space, Pu has been used in heart pacemakers and is still a candidate as a power source for completely artificial hearts. Production of Pu requires the isolation of Np, which is then irradiated and reprocessed to produce pure Pu. 

Kronauer, R.E. 1990. A quantitative model for the effects of light on the amplitude and phase of the deep circadian pacemaker, based on human data. In Sleep 90 (Proceedings of the Tenth European Congress on Sleep Research, Strasbourg), J. Home, ed. Pontenagel Press, Bochum, pp. 306-9. 

The development of biological pacemakers through the use of, for example, gene therapy, is an active area of cutting-edge pacing research. Other areas of likely evolution include the following ... 

The goal of these and other researchers was to develop a totally implantable pacemaker. Bioengineer Wilson Greatbatch and heart surgeon William Chardack achieved this milestone with their first successfiil human implant in 1960. Greatbatch used then-novel transistors and an epoxy-encased Ruben-Mallory zinc mercuric oxide battery in his design. [5]... 

The identification and development of materials that find application in biomedical applications has a profound effect on our quality of life. It is breakthroughs in this area of materials research that has seen the development of highly effective stents [1,2], bone replacements [3], pacemakers [4], bionic ears [5], and wearable prosthetics [6]. In each of the above examples the material requirements will differ. However, in all cases they must be compatible with the biological environment in which they are to operate. This compatibility may involve molecular and cellular interactions, be at the skeletal level wherein aspects related to wearability, comfort, lightweight, and esthetics become important. 

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