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                                Nanotechnology:
                         Manipulating Atoms One by One
                    by Robert Kulagowski and Loretta Kulagowski

       To understand the complex world of nanomachines, a basic understanding
  of the components must be gained. By definition the word nanotechnology
  means
        "technology based on the manipulation of individual atoms and
         molecules to build structures to complex, atomic specifications."
  Simply stated, this means using molecules to build larger, more complex
  structures.

       Even though nanotechnology is still in its infancy, it is being
  accepted more widely by the scientific community as something that is
  within the realm of possibility in only a few years.

       To begin to explain exactly what nanomachines are, it would be best to
  start with what they are made of. Normally, when people hear the word
  "machine", they tend to think of a large noisy object used to produce
  something. The literal definition of the term "machine" is:
        "any system, usually of rigid bodies, formed and connected to alter,
         transmit, and direct applied forces in a predetermined manner to
         accomplish a specific objective, such as the performance of useful
         work."
  A nanomachine is just such a system, but working on a molecular scale
  rather than on the macroscopic level.

      One aspect of nanomachines which many people do not realize is the fact
  that they exist at this very moment. Right now, in every living organism is
  a multitude of nanomachines whose purpose is to break down proteins,
  transport molecules across membranes, and even fix errors in the DNA
  structure of the nucleus. The only difference between the nanomachines in
  the body and those that scientists hope to artificially create is that man-
  made nanomachines will be much more general purpose.

       Nanomachines are made of protein molecules. Since the forces that hold
  proteins together are very weak, the probability that the protein would
  fold in the correct way is astronomical. This makes creating a large
  protein molecule extremely difficult. Current technology allows biochemists
  to create amino acid sequences from scratch, but with no guarantee as to
  the structure that will develop. Biochemists are now trying to figure out
  how to make a sequence of amino acids fold the right way. The best computer
  programs today still cannot predict how a given sequence will fold.

       On the other hand, engineers do not think the same way that
  biochemists do. The engineers are not trying to predict how natural
  proteins will fold, but are trying to design a long protein chain that will
  fold predictably, which makes the engineer's job easier in a sense.

       Once protein based nanomachines have been successfully created, the
  door will be open for nanomachines which are made of tougher stuff. The
  disadvantage of proteins is that they have a limited range of operating
  conditions: pH level, temperature and other factors must all be regulated
  to extreme precision.

       Nanomachines can serve many useful purposes. One field which can
  benefit greatly is medicine. Because nanomachines are specifically designed
  to manipulate single atoms, many of today's ailments can be cured
  relatively easily.

       One such condition is arteriosclerosis. In arteriosclerosis, deposits
  of cholesterol build up on the inner walls of arteries, causing them to
  narrow. This condition is most serious when the coronary arteries are
  involved. Although the heart is a small organ, it uses 1/5th of the blood
  supply for its own needs. When the blood flow is sufficiently restricted,
  tissue which is fed by that artery begins to die. The first sign of
  narrowed arteries in the heart is a condition known as angina, which causes
  sharp chest pain. As the condition worsens, the heart muscle will begin to
  die, which will cause a heart attack. However, a nanomachine can be
  programmed to search for deposits of cholesterol and remove them, thereby
  re-opening the artery.

       Cell repair nanomachines would handlethe problems that occur with
  cells and tissues. For this job, the cellrepair machines would need the
  assistance of nanocomputersand molecular-sized sensors and tools. These
  cell repairmachines would compare in size to bacteria and viruses, butbe
  much more complex. Cell repair machines would travel through the blood
  stream and would enter the cells as viruses do. Once inside thecell, the
  nanomachine would determine whether a problem existed by examining the
  cell's contents and activities. Depending on what was found, it would take
  the necessary action to either restore the cell to top efficiency or to
  destroy the cell if it were too far out of operational parameters, as is
  the case in cancer.

       In order to control the function of the nanomachine, a nanocomputer
  would direct their actions. The logic gates would be built by bonding
  carbon in this fashion:
                              (C <20> C  -  C <20> C)n
  where n is the number of units in the chain. The carbon atoms in this chain
  would form straight rods. Other atoms such as fluorine would be used as
  logic gates. Memory for the computer would be constructed on the atomic
  scale with different atoms representing binary 1's and 0's. Because the
  amount of RAM capacity is virtually limitless on the atomic scale, the sum
  total of human knowledge could be stored in the volume occupied by a sewing
  thimble. Since the amount of memory available for the nanocomputer would
  not be a factor, a nanocomputer would be able to read in the entire DNA
  sequence for a particular person and make corrections when necessary.

       Since all physical ailments of the human body are caused by
  misarranged atoms, cell repair machines would restore these atoms to their
  correct place, thereby eliminating the problem. As rosy as this may sound,
  simply repairing the physical ailment would not necessarily fix the main
  cause. For example, if a person were to have a stroke, the damaged brain
  tissue could be reconstructed, but any information stored in that cell
  would be lost.

       One area that would not be effectively treatable through
  nanotechnology is mental health. While some types of mental disability
  would by curable through the restoration of chemical and hormone levels in
  the brain, others which are not caused by physical means would not be
  affected.

            The problem of aging could also be solved by nanomachines. The
  weakened bones, wrinkled skin, low enzyme activities, slow wound healing,
  and poor memory, all typical examples of aging, would become unknown. All
  of the above side effects of aging are caused by damaged molecules,
  chemical imbalances, and misarranged structures. If cell repair machines
  could fix the damaged cells and structures, then the aging process would be
  greatly slowed down. Lives could be prolonged for almost an indefinite
  amount of time. The average life expectancy of a person could very well
  range into the hundreds or thousands of years. K. Eric Drexler, a pioneer
  in the field of nanotechnology, predicts that nanomachines would be able to
  restore people frozen in cryonic suspension. As a part of the unfreezing
  process, cell repair machines would fix the problem the person had which
  caused them to be frozen.

       Beyond the medical aspect, another field in which nanomachines would
  contribute is space technology. Because a nanomachine would construct
  something with precise knowledge of every atom, much of the problems
  associated with space today could be solved. Entire engines could be
  constructed in one piece, with no seams or structures that could be jarred
  loose by vibration.

       Toxic waste, the scourge of the modern era would be removed from our
  air, soil, and water. Many possibilities exist for dealing with this
  problem. One example: dioxin. Molecular machines could be created that
  simply rearrange the atoms in this substance, which would then render it
  harmless. To remove lead and other heavy metals, the cleaning-machines
  would construct a molecule of buckminsterfulerene with the heavy metal in
  the center. Briefly, a description of buckminsterfulerene: the nanomachine
  would create a three dimensional lattice of carbon atoms roughly in the
  shape of a ball. The toxin would still exist, but it would be in an inert
  form and unable to interact with the external world.

       Even though the widespread use of nanotechnology is still at least 10
  to 50 years away, it will come eventually. The enthusiasm with which the
  idea of nanotechnology has been received is almost a guarantee that someday
  in the future nanomachines will be chugging along through our bloodstream
  with our white blood cells.


                                 Bibliography

  Drexler, K. Eric, Interview with Eric Drexler, Omni, January 1989, pg 66
  Drexler, K. Eric, "The Engines of Creation: The Coming Era of
                     Nanotechnology", Anchor Press/Doubleday, 1987
  Fromson, Brett Duval, "Where the next fortunes will be made", Fortune,
                     December 5, 1988, pg 185
  Monmany, Terence, "Nanomachines to our rescue", New York Times Book Review,
                     August 8, 1988
  Young, Jefferey,  "Nanocomputer technology proves good things come in small
                     packages", PC Week, February 16, 1988, pg 13

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