- From: Michel_Dumontier <Michel_Dumontier@carleton.ca>
- Date: Thu, 2 Apr 2009 11:35:26 -0400
- To: "Egon Willighagen" <egon.willighagen@gmail.com>, "Matthias Samwald" <samwald@gmx.at>
- Cc: "Phillip Lord" <phillip.lord@newcastle.ac.uk>, "Oliver Ruebenacker" <curoli@gmail.com>, "Pat Hayes" <phayes@ihmc.us>, "public-semweb-lifesci" <public-semweb-lifesci@w3.org>
> -----Original Message----- > From: public-semweb-lifesci-request@w3.org [mailto:public-semweb- > lifesci-request@w3.org] On Behalf Of Egon Willighagen > Sent: Thursday, April 02, 2009 10:57 AM > To: Matthias Samwald > Cc: Phillip Lord; Oliver Ruebenacker; Pat Hayes; public-semweb-lifesci > Subject: Re: blog: semantic dissonance in uniprot > > On Tue, Mar 31, 2009 at 2:09 PM, Matthias Samwald <samwald@gmx.at> > wrote: > >>> Reaction equations describe stochastic processes, that's why you > can > >>> have non-integer molecule numbers > >> > >> I think you can't have non-integer molecule numbers because it makes > >> no chemical sense. Half a molecule is a whole molecule of a > different > >> kind. > > > > You can have reaction equations that look like > > > > N2O5 ---> 2 NO2 + 1/2 O2 > > > > Which means that the number of O2 molecules that would be produced if > the > > equilibrium would be shifted to the absolute right side is 1/2 of the > number > > of molecules of N2O5 that would exist if the equilibrium would be > shifted to > > the absolute left. This only makes sense if we interpret reaction > equations > > as descriptions of pools of molecules and their stochastic processes, > rather > > than single molecules. Representing reaction equations as processes > where > > the participants are single molecules is wrong. In that case, one > cannot > > blame OWL if one is running into inconsistencies. > > Actually, I'd say OWL is to blame here... that is, the OWL class was > not properly defined. Just to clarify - it's not OWL that's the problem. It's the representation of Chemistry in a formal logic-based language where it actually matters what you say and how you say it. > > Reaction Equations are a difficult concept, and depending on the > context mean different things. This discussions is just caused by > different meaning people give to Reaction Equation. Very typically, > you would even mix both types in reaction schemes (e.g. schemes where > both the overall as well as mechanistic reactions are given), even > though they refer to different concepts. In the BioPAX-OBO effort we have begun to address the distinction between a chemical reaction and a reaction equation. Indeed, it is useful to make the distinction, as they imply different things. -=Michel=- > > Egon > > -- > Post-doc @ Uppsala University > http://chem-bla-ics.blogspot.com/
Received on Thursday, 2 April 2009 15:37:13 UTC