What Does Dead Mean

All living systems must metabolize to obtain chemical energy in a form suitable to repair damage and maintain control over their inner workings. Any condition that interferes with these biochemical processes, such as oxygen deprivation, hypothermia, hyperthermia, or toxins, can cause 

FIGURE 6.23.1 Death comes to Mr. Potatohead. (Courtesy of Mother Goose and Grimm, Grimmy, Inc., King Features Syndicate, New York.) 

In humans, especially, death has been defined as no cortical activity. The brain has no oxygen or energy reserves, and it ceases to function adequately a few seconds after blood ceases flowing (Simpson et al., 1957). A nervous system is necessary for proper performance of all advanced animals, and when it no longer functions, death is said to occur. 

And then there are the psychosocial definitions of death, meant to satisfy complex legal requirements of human society. Clinical death occurs when there is no heartbeat and no spontaneous breathing (Smith, 1998). Brain death is characterized by no electroencephalogram (EEG) activity, a complete lack of reflexes, total failure to respond to stimuli and no breathing without a respirator. Social death involves terminally ill patients who are hospitalized for long periods before dying and require elaborate life-support equipment to maintain any semblance of life. 

Uprooting a plant shows how tenacious is life. The plant will begin drying almost immediately, the leaves wilt, and the nonwoody stems become flaccid. Yet, even several days later for some plants, plunging them back into water can revive them. Clearly, they were not completely dead. 

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You observe that you are going through a lot more reversed-phase columns than you used to and your columns die earlier. Your supplier is not too unhappy, but you would like to know the cause. What does it mean to have a dead column If we exclude higher back pressure, decreased quality means a decrease in the number of theoretical plates (broad peaks, the packing is not OK) and/or a change in retention time (chemical change of the stationary phase). What possible causes should be considered ... 

Bob Williams As a scientist I would say, that as far as reductionism is concerned, we could think how far physics has got. Now physicists would say that given the Big Bang at a tenth of minus fiftieth of a second, they can come all the way forward to the present time as far as most dead things are concerned, and they ve achieved that conclusion over a very long period of time. I don t know how far this reductionist game will go as far as living things are concerned. What I worry about is, if I am not allowed to say that all the scientific activity is in some way reductionist, what does holistic research mean. What is it exactly If somebody could answer what is holistic research, I would be very interested. 

What does the cell dry weight concentration mean and teach us about the progress and behavior of a bioprocess The analytical value reflects only the cellular mass and does not allow a distinction between structural or storage materials and biocatalytically active components of the cells on the one hand, or between live and dead cellular material on the other. 

How does one define ageing A relentless decline in faculties ending in death Or was that just a description If we can t define life, what on earth is death If a prion is not alive, is it dead If so, does that mean we can t kill it ... 

The use of hypertext in information science is superior to a traditional linear presentation. It relies on a tree structure. However, it has a serious drawback. Looking at a branch, we have no idea what it represents in the whole diagram, whether it is an important branch or a remote tiny one does it lead further to important parts of the book or it is just a dead end, and so on. At the same time, a glimpse at the TREE shows us that the thick trunk is the most important structure. But what do we mean by important At least two criteria may be used it is important for the... 

What if you are told that i ° = 0 for an electrolytic cell Does this mean the cell is dead What if = 0 Explain your answer in each case. 

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