Thursday, February 26, 2009

Limited Undo

It's great when you can undo after you have already saved a document and go back, back, back... It would be even greater if everything could be really undoable. Take for example Adobe(R) Acrobat(R) Reader 9.0.0. I was reading a book of 1200 pages. I was reading one of the internal pages (don't remember which) and had arrived to the bottom of the window. I moved my hand to press the key "Page Down", but I pressed the wrong (nearby) key, which happens to be the "End" key. Ok, I said, there's the Undo command. No way, said Acrobat Reader, you can't undo. The rationale is probably: "The user has not edited the document, there is nothing to undo". Why not adopting the rationale: "Every time a key is pressed, chances are it was a mistake"???
Dear reader, don't think that, just because today's software allow for unlimited undoing, you can really undo everything. Actually there are a lot of important and common things that can't be undone, or can be remedied to, but only using a command different from Undo. Try for example to click a link in this page and to return here with an Undo. Does it work? Try typing a long sentence with your word processor and to remove the last word only with Undo. What happens?
Luckily, everybody knows how to jump back to the previous page with the command go back and to delete the last word by selecting it and cutting it away. How do you find the page you were reading with Acrobat?
Adobe Reader takes 172.6 MB on my hard disk. It's larger than many historical operative systems (combined). It's also much larger than my first hard disc (40 MB), yet it can't undo. It's really a mystery what's hidden inside. There is potential room for a million of viruses.
I have an assignment for you. I mean you guys who haven't the least idea of what NMR means but nonetheless try to post comments into my blog only to link to your web sites. I have always deleted your posts. This time I want to give you a chance.
Read the credits of Adobe Reader (they appear after you open the "about" box). If you can write the exact number of people who appear into the credits, I will not delete your comment.

Friday, February 06, 2009

New Millennium

What's the difference between the old and the new millenium? Do you remember when I described the whitening method? Now it has been published, as a peer-reviewd article, on Magnetic Resonance in Chemistry:
Automatic phase correction of 2D NMR spectra by a whitening method
Giuseppe Balacco, Carlos Cobas
Published Online: Feb 3 2009 10:57AM
DOI: 10.1002/mrc.2394
If you have followed this blog, you know that many other papers have appeared on a similar subject (automatic phase correction of 1-D spectra). In the past, to discover that the method didn't actually work, you had to write a program by yourself (apart a few lucky exceptions). If you want to verify the whitening method in practice, you have plenty of simpler and faster alternatives.
You can download iNMR Passion (freeware) or you can download the freely accessible iNMR (or iNMR reader: they don't allow printing, in demo mode, which is irrelevant in our context). If you have a generic operative system you can ask for a demo copy of MestreNova.
Please don't complain if some of these products are commercial. FTF: where do you publish your results? On your own blog? Second thing: we haven't patented our method and anybody is free to include the algorithm into her/his own program (free or commercial); citing the source would be fair.
A final disclaimer: the whitening method works nicely in 2-D spectroscopy. It's not yet applicable in 3-D cases. When, however, the phase of a 2-D spectrum is impossible to correct manually, it's also impossible to correct it automatically. Obvious!

Monday, February 02, 2009

N as FID

A bidimensional Free Induction Decay of an aqueous solution.

Sunday, February 01, 2009


do you recognize it? can you do the same?

Desktop Pictures

These images are 1680x1050 JPEGs because these are the dimension of my screen. It's a C-H HSQC of ubiquitine at 500 MHz, fully processed.


The above image has been generated without shades and 3-D effects: it's a plain flat map. All the optical effects come from the spectrum itself. Positive points are black, negative points are red. Click the image to see it larger.