[ccp4bb] Off-topic: Crystallographic Symmetry Applications Available?

2013-07-31 Thread Chen Zhao
Dear all, I have been trying to search for some softwares/applications that can display the crystal space group "lattice" based on the input of cell dimension and space group. Ideally, it can also apply the arbitrary symmetry operation to a molecule with given orientation and position in the unit

[ccp4bb] Postdoctoral position at UT Southwestern

2013-07-31 Thread YuhMin Chook
The Chook Lab (http://www4.utsouthwestern.edu/chooklab/index.htm and http://profiles.utsouthwestern.edu/profile/53719/yuh-min-chook.html) in the Departments of Pharmacology and Biophysics at UT Southwestern seeks a postdoctoral fellow who is both a trained crystallographer and an excellent bioc

Re: [ccp4bb] Advice on setting up / maintaining a Ubuntu cluster

2013-07-31 Thread Mark van der Woerd
Dear Sergei, Many have already given good advice. A somewhat different approach: You might want to consider using a NAS for user file and program storage. We have run a group of Linux PCs for years that way and we are quite pleased with it. The NAS would take the place of your file server PC.

Re: [ccp4bb] delete reflections with negative peak profile correlation

2013-07-31 Thread
Hi Kay, Thank you and Andrew very much. The paper you cited is really helpful!

[ccp4bb] Postdoctoral opportunity at the EMBL Hamburg

2013-07-31 Thread Victor Lamzin
Dear All, We are seeking a highly motivated researcher, preferably a fresh PhD graduate, for a postdoctoral position in the area of in silico ligand-based drug design (http://www.embl-hamburg.de/training/postdocs/08-eipod/application/04_2013_project_ideas/lamzin.pdf). The position is withi

Re: [ccp4bb] Placing coordinates and mtz reflections file on a common new origin

2013-07-31 Thread Mo Wong
Many thanks for the reply. Unless I have not RTFM properly, cphasematch only modifies one column of phases at a time, and outputs the modified phases to a new column. It also doesn't appear to take a reference PDB (corresponding to the reference mtz) as a means to calculate the appropriate rot/tra

Re: [ccp4bb] Advise on setting up/ maintaining a Ubuntu cluster

2013-07-31 Thread Kay Diederichs
I was hoping to avoid this discussion ... It is true that if the server dies, you loose your data. But for crystallographic calculations, this is true for "async" as well as for "sync". Just repeat the calculation if it dies midway - it's as simple as that. This is probably very different for ai

Re: [ccp4bb] Advise on setting up/ maintaining a Ubuntu cluster

2013-07-31 Thread Robert Esnouf
At high load levels "async" is a dangerous option. What it means is that when an NFS client has copied its data to the NFS server (i.e. memory, not disk) it accepts the acknowledgment and carries on assuming the data have been committed. The "sync" option means that the acknowledgment is not sen

Re: [ccp4bb] Advise on setting up/ maintaining a Ubuntu cluster

2013-07-31 Thread Dmitry Rodionov
We don't have any performance/ reliability issues with our cheapskate setup either. Make sure the network is wired with Cat5e or Cat6 cables, especially if distances are 8m+ Dmitry On 2013-07-31, at 7:36 AM, Kay Diederichs wrote: > I have a very different experience with NFS: we are us

Re: [ccp4bb] Output of Phaser

2013-07-31 Thread Randy Read
Hi, What I meant is that the solution that showed the TFZ-equivalent score for the second component should have been the one with the highest LLG after adding the second component, and it wasn't in your example. That's why I thought you must have made it up. Randy On 31 Jul 2013, at 12:30, C

Re: [ccp4bb] Advise on setting up/ maintaining a Ubuntu cluster

2013-07-31 Thread Dirk Kostrewa
We have a very similar setup, and I can only second Kay's experience. Best regards, Dirk. Am 31.07.13 13:36, schrieb Kay Diederichs: I have a very different experience with NFS: we are using Gigabit Ethernet, and a 64bit RHEL6 clone with ECC memory as a file server; it has RAID1 ext4 home d

Re: [ccp4bb] Advise on setting up/ maintaining a Ubuntu cluster

2013-07-31 Thread Kay Diederichs
I have a very different experience with NFS: we are using Gigabit Ethernet, and a 64bit RHEL6 clone with ECC memory as a file server; it has RAID1 ext4 home directories and RAID6 ext4 for synchrotron data. We have had zero performance or reliability problems with this in a computer lab with ~ 10

Re: [ccp4bb] Output of Phaser

2013-07-31 Thread Chen Zhao
Dear Prof. Read, Thank you for your detailed explaination. I think now I am clear about what each set of scores represent. But what do you mean by what the .sol should show? I did "make it up" by selecting two solutions sets from two different runs, and I am sorry for not making it clear at the be

Re: [ccp4bb] Placing coordinates and mtz reflections file on a common new origin

2013-07-31 Thread Kevin Cowtan
cphasematch should do the job. I presume you did a structure factor calculation for one or both models? I'm not clear what the problem is with that. Is it that it is giving you the wrong shift? On 30 July 2013 14:33, Mo Wong wrote: > Hi all, > > I am trying to get multiple molecular replacemen

Re: [ccp4bb] Output of Phaser

2013-07-31 Thread Randy Read
Dear Chen, For each component that is placed, Phaser reports the Z-scores for the rotation function (RFZ) and translation function (TFZ), along with the number of packing clashes (PAK) at this point and the LLG. For the top solution at that point in the search, Phaser also reports the TFZ-equi

Re: [ccp4bb] delete reflections with negative peak profile correlation

2013-07-31 Thread Kay Diederichs
Hi, I completely agree with what Andrew writes. It's very easy: negative CORR means that the reflection profile after background subtraction has a negative correlation coefficient with the standard profile. How can this happen? Well, this situation occurs when the reflection is very weak and th

Re: [ccp4bb] delete reflections with negative peak profile correlation

2013-07-31 Thread Andrew Leslie
Dear Rain, I will let XDS expert users provide the definitive response to this because I'm not certain what exactly a "negative peak profile correlation" indicates. However, I would be very cautious about deleting reflections simply to improve the reported statistics. Taken t