Search found 188 matches

by Samuel Flores
Wed May 31, 2017 3:01 pm
Forum: Simbody: SimTK multibody dynamics API
Topic: Can't figure out: binding dereferenced null pointer to reference has undefined behavior
Replies: 5
Views: 531

Can't figure out: binding dereferenced null pointer to reference has undefined behavior

Guys, I am getting a puzzling warning when building the latest release of simbody. Actually it only occurs when building examples, but since I am having problems downstream I think this needs to be addressed. The warning is below. Any advice? Thanks Sam In file included from /Users/Sam/github/simbod...
by Samuel Flores
Thu Apr 27, 2017 12:42 am
Forum: MMB (formerly RNABuilder)
Topic: MD run explodes
Replies: 5
Views: 823

Re: MD run explodes

Sorry I seem to be missing these messages. 1. You can expect unphysical results if parts of your molecule are flexible and physics is not turned on, or is not turned on for enough of the nearby residues. For homology modeling you have to be very careful to keep the MD forces turned OFF for the templ...
by Samuel Flores
Thu Jan 12, 2017 1:52 am
Forum: MMB (formerly RNABuilder)
Topic: MD run explodes
Replies: 5
Views: 823

Re: MD run explodes

Hi Xiong An, I made a few modifications to your script. Assuming you are using the latest build, it will be easier to work this way. First, you can just issue "mobilizer Rigid" to rigidify everything, and then set 51-69 back to being flexible. You can use nucleicAcidDuplex to make base pairs in a do...
by Samuel Flores
Tue Jan 10, 2017 5:46 am
Forum: MMB (formerly RNABuilder)
Topic: MD run explodes
Replies: 5
Views: 823

Re: MD run explodes

I would use "Default" rather than "Free". Free confers 6 degrees of freedom (DOFs) for each bond. Default makes most bonds either Torsion (1 DOF) or Rigid (0 DOF). Rigid is for groups like phenols, or the peptide bond, that MMB prefers to treat as though they had no internal DOFs. Anyway, Free costs...
by Samuel Flores
Thu Dec 29, 2016 9:07 am
Forum: MMB (formerly RNABuilder)
Topic: Naive Question : What is RNA threading and morphing
Replies: 2
Views: 392

Re: Naive Question : What is RNA threading and morphing

Oh sorry by threading I meant homology modeling. Where did you see the term "threading"? MMB was the first homology modeling method for RNA. You can read about it here: http://psb.stanford.edu/psb-online/proceedings/psb10/flores.pdf Morphing is just finding a trajectory connecting two known structur...
by Samuel Flores
Sat Oct 15, 2016 3:46 am
Forum: Simbody: SimTK multibody dynamics API
Topic: incompatibility between Constraint::Weld and LocalEnergyMinimizer::minimizeEnergy ?
Replies: 3
Views: 380

Re: incompatibility between Constraint::Weld and LocalEnergyMinimizer::minimizeEnergy ?

In this case the complexes AB and CD are highly similar. So constraining A to B should give almost the same result as not constraining -- the differences should be on the order of tenths of Ångströms (there will be other situations in which this is not the case, hence the need for constraints). Howe...
by Samuel Flores
Fri Oct 14, 2016 2:22 am
Forum: Simbody: SimTK multibody dynamics API
Topic: incompatibility between Constraint::Weld and LocalEnergyMinimizer::minimizeEnergy ?
Replies: 3
Views: 380

incompatibility between Constraint::Weld and LocalEnergyMinimizer::minimizeEnergy ?

Guys, Is there an incompatibility between Constraint::Weld and LocalEnergyMinimizer::minimizeEnergy ? I create one complex comprising proteins A and B, which are constrained to each other (I want them to stay together, moving as a single rigid body) and then apply springs to pull them onto another c...
by Samuel Flores
Thu Sep 22, 2016 10:31 am
Forum: MMB (formerly RNABuilder)
Topic: My first few runs to determine microRNA structure
Replies: 3
Views: 536

Re: My first few runs to determine microRNA structure

Hi Kamlesh, I am not sure I would recommend this approach. You can eventually get this to fold but it will be prone to kinetic traps. We got out of those using the Scrubber as described in the RNA and TCBB paper, but it took some patience. At the time it made sense because there was plenty of low-gr...
by Samuel Flores
Thu Sep 22, 2016 9:58 am
Forum: MMB (formerly RNABuilder)
Topic: Target RNA structure automatically modified before threading
Replies: 3
Views: 560

Re: Target RNA structure automatically modified before threading

Hi Crystal, I just realized I didn't answer you earlier. Bug me if that happens! Before I tell you the answer, I intended for MMB to be as easy to use, and as flexible with respect to the structural and other data it takes, as possible. I also intended for MMB not to think too much for you, as guess...