Science Vol 268 #5211 5, May 1995


+
 Exploring Transgenic plants as a new vaccine source

-Plant biotechnology, possible to use genetically engineered plants
and plant viruses to produce vaccines vs human diseases from tooth decay
to infections (bacterial ...).  Possibly building vaccines into plants eaten




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+
 Plants as Chemical Factories 

w/ Recombinant DNA
-Genetically engineering cotton plants to produce
fibers w/ polyester-like compound in the normally
hollow fiber cores .

-Making biodegradable plastics, industrial lubricants, feedstocks for soaps and detergents.  Drugs and pharmaceuticals.  Potential new vaccines.


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+
Loss of Atmosphere from Mars from Solar Wind-Induced Sputtering 

-w/ no strong intrinsic magnetic field, the
atmosphere is eroded by interactions w/ the solar wind.  Early solar-system
conditions enhanced sputtering loss.
~3 bars of CO2 have been sputtered of 3.5 bil years. Geomorphology.



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+
 Throwing a Switch on a Nanoscale Sieve

-Motors/gears width of human hair
-Wires a few atoms across
-chemical rx one molecule @ a time.
-molecular sieves w/ pores as small as 1.6 nm.
-Membrances adjust to let ions pass by changing its electric potential.
-a model for ion-selective membranes.
-ion transport problem.
-2 gold layers connected by strands in the membrane.
-create gold tubes through the pores instead of wires.
-gold plating to put electrical charge on the tubes to control types of ions they let through.




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+
Edging to Supersymmetry 

-search for electric dipole in atom.=tiny separation between centers of + & - charge
-line up magnetic spin of Hg atoms, push w/ e field , probe for wobble of dipole.
-This wobble if it occurs would support theory called supersymmetry

SUPERSYMMETRY
-Supersymmetry creates a single framework for 2 basic kinds of particles in nature - force carrying particles (bosons: e.g. photons ) and
matter particles (eg quarks, electroncs), and posits massive, 
shadowy partners for known particles.  These particles would 
materialize only at energies higher than the largest accelerators 
can muster.  But quantum mechanics grants 
even particles that aren't at home at everyday energies a fleeting presence as "virtual particles" that wink in and out of existence.
Like ghosts that subtly rearrange a room while no one is looking the virtual supersymmetric particles would interact w/ the quarks in an atom's protons and neutrons , leaving a mark in  the form of a tiny electric dipole.





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+
New Superconductor Stands Up to Magnetic Fields 

For HTS, B fields are bad.
-HTS materials capable of carrying big i(current) wo/ resistance.
-In a B field their current carrying ability plummets. (eg. MRI)
-Until recently only way to combat B field was to chill HTS do 20degrees K.
-requiring liquid He.

FLEXIBLE SC TAPE @ 77K B Shielding
-Los Alamos - A flexible SC tape stands up to Hi B fields @ 77K.
-Tape packs powerful electrical punch.
-More than 1 million amps of current per cm^2.
-at 77K, HTS magnets and motors made w/ this material
could be cooled to 47K
-materials deposition.
-HTS wires w/ Bismuth / Thallium ceramics
w/ good grain alignment.


YBCO
-ceramic superconductor of yttrium, barium ,copper , oxide (YBCO)
-Lay crystals on template, start w/ Nickel alloy base.  Laid down template layer.  Then Yttria-stabilized zirconia (YSZ) w/
ion beam-assisted deposition (IBAD) grows YSZ crystals on nickel allow w/ 1 orientation. Since YBCO's lattice has structure follows YSZ orientation.

Achieve 500,000 A/cm^2.


--fin