Science Vol 268 #5209 21, April 1995


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 A Molecular Approach to Cancer 
     Mechanism Studies
       - How a substance triggers cellular changes , forming DNA adducts, increasing
         cell proliferation, perturbing intercellular communication
     Pharmacokinetics/Pharmacodynamics
       - How a substance is absorbed, distributed, and
         metabolized in the body.
     Structure-activity relationship analysis
       - How an agent's molecular size, shape and electrical properties might influence its toxicity
     New animal models
       - Carcinogenicity tests in transgenic mice and medaka fish


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 Orientational and Magnetic Ordering of Buckyballs in TDAE-C60 
  Spin ordering in the low-temperature magnetic phase is directly linked to the orientation ordering of C60 moleculres 
in organically doped fullerene derivatives. Electron-spin resonance and alternating current susceptometry measurements on tetrakis (dimethylamino)ethylene-C60 (TDAE-C60) (Curie temperature Tc=16K) show a direct
coupling between spin and merohedral degrees of freedom.  This coupling was experimentally demonstrated by showing that ordering the spins in the magnetic phase imprints a merohedral order on the solid or, conversely, that
merohedrally ordering the C60 moleculres influences the spin order at low temperature.  The merohedral disorder gives rise to a distribution of pi-electron exchange interactions between spins on neighboring C60 molecules, suggesting a microscopic origin for the observed spin-glass behavior of the magnetic state.

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 Dwarfs and Dim Galaxies Mark Limits of Knowledge 
  "At home in the early universE"
  -Uniform gas cooling from temperature of millions of degrees (early universe)
  -1. Cosmic background radiation, dates from point
      at which universe had cooled enough to become transparent
   2. Cosmic abundance of helium which traces element-forming 
      processes in the hot gas.
  -Before 1st millisecond? uncertain.
       Maybe drastic growth spurt (inflation) high-energy quantum cosmology.
  -Also 1st million years -
  "Awash in Dim Galaxies"
  -To explain how individual galaxies move within galaxy clusters
      requires gravitational pull of 10x more matter than can be seen in 
      stars/galaxies (dark matter)
  -Astronomers may have overlooked at many as half of the galaxies
      in the known universe! because they are dim galaxies.
  -Using multiple mirror telescope & 305m radio dish
  Telltale Dwarfs
  -By measuring temperature of cluster's white dwarfs, evidence that stellar cinders have been cooling longer than accepted age of the cluster.
 So standard way to model way stars evolve in error.
  -Est. age by checking brightness and colors of stars vs stellar evolution models, predict how these should change over time.
   -More direct check cluster's dimmest white dwarfs.  Since they no longer produce energy, cool @ steady rate.
   -Since oldest dwarfs in a cluster are the cinders of stars that burned only briefly afterit formed, their age is a good proxy for the age of the cluster.
   -But cool white dwarfs are by nature hard to see -> Hubble Space Telescope.
  -NGC2477 white dwarf stars dervied age of 1.25bil years.  That's more than twice the gae calculated based on stellar evolution models.
  -Also other clusters placed at age of 12 bil years.  Greater than recent estimates of the age of the universe as a whole!
   -Based on universe expansion -> ext of universe = 8bil years.


--fin