GIF EM FILES

[jean-yves sgro]

 C.J. Woolston has uploaded his digitized EM microgrpahs on my site
and they are available right now. Below is the README file which will
tell you everything you need to know.

Jean-Yves

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NOTE: PARAGRAPHS START WITH @- FOR EASY TEXT SEARCH ON A COMPUTER


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                     Digitised Electron Microgphs
                          of Plant Viruses
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        © 1994 Thorben Lundsgaard, C.J. Woolston and Ed Rybicki

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Copyright notice: This notice must accompany any copy of the distributed
images. Images cannot be used for commercial purpose without the consent
of the copyright owners. Images are NOT in the public domain. Images can
be freely used for educational purposes.
(c) 1994 Thorben Lundsgaard, C.J. Woolston and Ed Rybicki
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@- IMAGE ORIGIN AND RESTRICTIONS:
   -----------------------------
These images were mainly kindly provided by Thorben Lundsgaard 
and Ed Rybicki but some are my own. Whilst it is likely that we will 
be happy to let you use these images for educational purposes, you should 
bear in mind that we retain copyright - these images are not public domain. 
They must not be used for commercial gain or profit without the express 
permission of the copyright owner(s).

@- WHERE TO FIND THEM:
   ------------------

Images are currently available on Jean-Yves Sgro's anonymous ftp site

at                 rhino.bocklabs.wisc.edu [144.92.19.130] 
in the             /pub/EM-GIF directory.


@- WHAT IS CURRENTLY AVAILABLE: (REVISED LAST: 16 MAR 94)
   ---------------------------

Not all groups of plant viruses are covered, but it is hoped that the 
collection will eventually expand to include the missing groups.

So far there are good quality images of:

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VIRUS FAMILY            VIRUS EXAMPLE                 PRINT MAGNIFICATION
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                       Alfalfa mosaic virus           240,000 
Bromovirus             Brome mosaic virus             currently unknown 
Carlavirus             Potato virus M                  36,000
Caulimovirus           Cauliflower mosaic virus        70,000
Closterovirus          Beet yellows virus             121,500 
Comovirus              Cowpea mosaic virus            220,000 
Cucumovirus            Cucumber mosaic virus          290,000
Geminivirus            Wheat dwarf virus              270,000
Nepovirus              Arabis mosiac virus            180,000
Potexvirus             White clover mosaic             68,000
Potyvirus              Beet mosaic virus              128,000
Rhabdovirus            Festuca leaf streak            300,000
Tobamovirus            Tobacco mosaic virus            65,000
Tobravirus             Tobacco Rattle Virus           113,000
Tymovirus              Turnip yellow mosaic           180,000
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@- DIGITIZATION PROCESS: IDEAS FOR CUSTOMIZING THE IMAGES
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These images were scanned (digitized) from photographic prints at a resolution 
of 180 dpi at 8 bits/pixel (256 levels) greyscale. No images enhancement 
or retouching has been done. I thought that this was best left to personal 
taste. A simple bit of maths should allow you to add a scale bar (you know 
the print magnification and you know how many dots (pixels) per inch the 
image was scanned at. For example, on the Potexvirus image (68,000x) 
a 180 pixel (1 inch) bar would be equal (approximately) to 3,736 nm. 

@- FILE FORMAT AND TRANSFER TIPS:
   -----------------------------

The scanned files have been converted to the GIF87a format retaining
all 8 bits/pixel gray scale information. There are numerous viewers for
this format for virtually every computer whether Macs PCs and Unix machines.

Those of you using  Macintosh computers will need to set the file type 
using a utility like FileTyper, as the GIFs on the ftp machine do not have 
a resource fork. Alternatively they can be opened in a program like Photoshop 
with the OPEN AS... command. Transfer should be done with "binary" turned on and
Mac users must make sure that binary and NOT Mac Binary is used.

@- CONTACT:
   -------

If you have any questions about these images, or would like to donate 
some to this collection, then please contact me:

E-mail - c.j.woolston at appbiol.hull.ac.uk
Post   - Dr. C.J. Woolston
         Department of Applied Biology
         University of Hull
         Cottingham Road, Hull, HU6 7RX, UK
Phone  - +44 482 465549
Fax    - +44 482 465458
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