- Chimera-users - RBVI Mailing Lists

Expanding EMdatabank map to full map
by Jason C Porta 03 Mar '14

03 Mar '14

Greetings, I am searching for a way to take a map from the EMdatabank which is just a cut-out of an icosahedral asymmetric and generate the full map via the sym operators. I see there are similar options for generating sym-related models, but is there a way to do this for a section of a map in Chimera? Many thanks, Jason P

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pocket cavity file produced by rdock
by Fabian Glaser 02 Mar '14

02 Mar '14

Hi all, I am trying to upload and examine the cavity file produced by the rbcavity program from rdock, an open source docking program. There are both a binary form and a regular file "RBT FFT GRID" but I am not able to upload or visualize them. Can you please help me to do it? Files are attached. Thanks a lot, Fabian

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Using sym command to generate icosahedral cage
by Yen-Ting Lai 25 Feb '14

25 Feb '14

Hi, I noticed that the sym command can be used to generate icosahedral symmetry, but it requires that the molecule to be oriented in specific ways (222, 2n5, n25, ...), which requires aligning the symmetry axes to the X, Y or Z axes. I am wondering if there is a way to specify the symmetries axes by vectors (instead of aligning them to the three principal axes) and then use sym command to generate the whole icosahedral cage? Yen

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Chimera hardware resources
by Derrick Smith 18 Feb '14

18 Feb '14

Hi Chimera users, I've been working with what are probably some pretty big files (400 MB - 3 GB) for ultramicrotomed sections of holograms. I've trimmed the volume down as well as I can while keeping it large enough to see what we ultimately were aiming for. However, I am running into some hardware resource issues. None of our computers in the lab can handle it, so I've been using my gaming rig at home to do it. I run a server off it also, so have some decent hardware to work with, but I cannot figure out how to reallocate the resources that Chimera seems to default to. I have 64 GB of system RAM available, and after recording 1-2 movies of rotations or a flythrough of clippings etc. Chimera has never used more than 1.5 GB. My graphics card has 4 GB. After filtering and post-processing, before any rotation or video capturing, the vid card has used around 2 GB already. During video capture, depending on if I'm rotating or clipping (clipping uses up a lot more faster), the vid card memory slowly gets eaten up, eventually crashing Chimera altogether. I can usually only get about 800-1000 frames before this happens on a smaller file (400 MB), and usually can't get through a whole 10s, or 250 framed, video on one of the larger files. I have pretty limited experience with this program, so I'm hoping it's a simple settings or otherwise fix I've overlooked. Any suggestions on this? Best, Derrick -- Derrick Smith Drexel University Soft Materials Group Philadelphia PA 19104 dms348(a)drexel.edu http://www.mse.drexel.edu/srg/

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Receptor-Ligand bonding at the LBP
by Graziella Portelli 13 Feb '14

13 Feb '14

To whom it may concern I would like to ask if there is a function where the bonds with which the ligand binds inside the LBP of the receptor would be visualised, or whether one has to search the amino acids involved in binding with the ligand one by one? I thank you in advance for your time Graziella Portelli

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Symmetry-aware segmentation?
by Joel Meyerson 13 Feb '14

13 Feb '14

Is it possible for Chimera to segment with an awareness of symmetry, such that the collection of segments in the asymmetric units are identical? For example, a molecule with C2 symmetry would have two copies of each segment. Also, is it possible to select a segment and then have Chimera further sub-divide that segment into additional segments? Thanks, Joel

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when will NoResidueRotamersError be raised?
by Xiao-Bo Li 13 Feb '14

13 Feb '14

I would like to mutate one residue to another. So far, the only way I found is to use the rotamers of the other residues on the original. I'm using chimera's python script. I would like to know if the NoResidueRotamersError will only be raised for residues that don't have rotamers like GLY. If not, then how can I replace the amino acid residue that I want to mutate? I am using the "getRotamers" function, which returns this error. XBL

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Problem in using BondRot
by amin＠imtech.res.in 13 Feb '14

13 Feb '14

Dear Chimera users, I am trying to write a script to change the phi and psi angle of a peptide. I am trying to adapt the code from http://plato.cgl.ucsf.edu/pipermail/chimera-users/2005-September/000456.html . I am trying to invert the angles so I am multiplying the angles by -1. My code is import chimera from chimera import selection, UserError, BondRot, replyobj opened = chimera.openModels.open('fun.pdb') mol = opened[0] RES_LIST = mol.residues for res in mol.residues: b = str(res.phi) if b != 'None': c = -1*float(b) atomsMap = res.atomsMap N = atomsMap['N'][0] CA = atomsMap['CA'][0] C = atomsMap['C'][0] CAmap = CA.bondsMap phiBond = CAmap[N] psiBond = CAmap[C] phiAnchor = N psiAnchor = CA phi = BondRot(phiBond) phi.setAngle(c, phiAnchor) When I run this script i get the error phi.setAngle(c, phiAnchor) AttributeError: '_molecule.BondRot' object has no attribute 'setAngle' Can someone please help me with this? Warm regards. Amin.

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un-subscribe
by Ted Holman 12 Feb '14

12 Feb '14

hi there i made a mistake and signed up for the email questions on chimera to be copied to me. i tried to un-subscribe but it did not work. can you tell me how to do this? thanks ted ___ Ted Holman, Ph.D. Professor Chemistry and Biochemistry Department 250 PSB, Thimann Receiving University of California, Santa Cruz Santa Cruz, CA 95064 Phone: 831-459-5884 Email: holman(a)ucsc.edu

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vrml lighting
by Dougherty, Matthew T 12 Feb '14

12 Feb '14

I have a multiple vrml models that vary by scale. 1, 10 & 100 I notice the lighting significantly drops off as the scale increases. When I have another model, say PDB, that is in approximate relation (ie, viewable in regards to the volume size similar to the vrml files volumes); the PDB file looks good regardless of size (eg, tRNA or ribosome). I can increase the brightness to compensate (10-20) but it washes out the PDB models when brightness goes beyond 2. is the lighting handled differently between these different types of models? Matthew Dougherty National Center for Macromolecular Imaging Baylor College of Medicine

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superimposing two structures based on a specific selection
by David Martin 10 Feb '14

10 Feb '14

Chimera 1.8 on Windows I have been trying to align (superimpose) models based on a specific conserved region. Unfortunately Chimera doesn't seem to do what the documentation claims it does. I run (example): match #0:5-15@CA,20-30@CA #1: 5-15@CA,20-30@CA and get an RMSD calculation (more on this below), but no movement of the model occurs. I specify 'move true show true' as options. Still no movement but I have a transformation matrix. Unfortunately this is not in a form that can be understood by Transform Coordinates. How do I persuade my structures to superimpose on the specific atoms? The RMSD calculation appears to be broken. If I take the command rmsd #0:5-15@CA,20-30@CA #1: 5-15@CA,20-30@CA then I will get a number If I then run rmsd #0:5-15@CA,20-30@CA #1: 5-15@CA,21-31@CA I get exactly the same number. In fact, if I specify atom sets of different sizes (as long as it is not the first block) then I continue to get exactly the same number rmsd #0:5-15@CA,20-30@CA #1: 5-15@CA,20-35@CA This should fail but doesn't Have I completely misunderstood what Chimera should be doing here? ..d The University of Dundee is a registered Scottish Charity, No: SC015096

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Query on introducing an external protein
by Aditya Padhi 06 Feb '14

06 Feb '14

Dear All, I want to place a protein molecule (appx. 20 kDa in size) into a viral capsid loop region which is about 7 amino acid long. What I want to do is to remove the 5 amino acids out from the loop region and place the 20 kDa protein, so that the loop region can accommodate the 20 kDa protein. I am finding it difficult as the co-ordinates of both the molecules are different. Although, this is not related to MD simulation or associated stuff, it would be grateful if I can get some suggestions. Thanking you, Regards Aditya.

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Query on introducing a protein
by Aditya Padhi 04 Feb '14

04 Feb '14

Dear All, I want to place a protein molecule (appx. 20 kDa in size) into a viral capsid loop region which is about 7 amino acid long. What I want to do is to remove the 5 amino acids out from the loop region and place the 20 kDa protein, so that the loop region can accommodate the 20 kDa protein. I am finding it difficult as the co-ordinates of both the molecules are different. Although, this is not related to MD simulation or associated stuff, it would be grateful if I can get some suggestions. Thanking you, Regards Aditya.

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Question about "Color Zone" and "Render by Attribute"
by Helge Paternoga 04 Feb '14

04 Feb '14

Hello, I have a question regarding the colouring of surfaces and their caps. I am trying to recreate the colouring by hydrophobicity on capped surfaces as shown in (on the right side): http://www.cgl.ucsf.edu/chimera/docs/ContributedSoftware/2dlabels/2dlabels.… So first I've opened the "Render by Attribute" dialog and assigned "kdHydrophobicity". This only coloured the surface and not the surface cap though. I am assuming this is done by "Color Zone"? Indeed this colours the surface cap but I have one problem: The colouring of the surface is different between "Render by Attribute" and "Color Zone" and I don't know why. The differences are small but I would like to know which one is more accurate (intuitively I would say the one from "Render by Attribute"). I've played around with the radius of "Color Zone" but this doesn't achieve the same colouring as "Render by Attribute". So my question is: How can I achieve the same surface colouring by "Color Zone" as in "Render by Attribute"? Does it have something to to with "bondzone" or the hierachy in which the atoms apply their respective colour in "Color Zone"? Thanks for reading! Helge

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Question about opening mrc and PDB files
by Min Woo Sung 03 Feb '14

03 Feb '14

Hi, This is Min Woo Sung from Texas A&M University. I was using Chimera to see EM structure(.mrc file) and wanted to put a PDB file to fit that in EM map. I'm wondering if I can use Chimera to analyze the volume, size or domains of these two files for the purpose of analysis. I saw one PDB file seemed much bigger that EM map when I opened it in Chimera. Do I have to normalize the size of any files? If so, how can I do that? Any suggests would greatly appreciated. Best regard, Min Woo Sung

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Creating output with IDATM naming
by Nikolay Igorovich Rodionov 03 Feb '14

03 Feb '14

Hi, Does anyone know a way to rename all of the atom names in a PDB file to their IDATM types, so that a new PDB file can be generated with the IDATM naming scheme? Best, Nikolay Rodionov

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Zoom problem?
by Damien Larivière 03 Feb '14

03 Feb '14

Dear all, I try to zoom in the scene, to get very close to my model shown here below. I cannot be closer than in the image below, the zooming function is at its maximum. When zooming, I get the error message : /refocus to continue scaling/ I do not know whether it is a bug or something I'm doing wrong. Thanks for your help, Damien

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Need help in Coulombic surface coloring
by Haresh Tukaram More 30 Jan '14

30 Jan '14

Hi, I tried to get the Coulombic surface coloring for one of the protein that I modified by removing certain residue at the C-termini and then mutated some residues to the non-natural amino acid 5,5,5-trifluoroleucine using Swisssidechin option. I am getting this error which I am not able to understand. Disabled GPU programs because a graphics driver bug was encountered while compiling a vertex shader. #0, chain A: COMP #0, chain B: COMP #0, chain C: COMP #0, chain D: COMP #0, chain E: COMP C:\Program Files\Chimera 1.8.1\bin\mscalc.exe 1.400000 2.000000 1 MSMSLIB 1.3 started on Local PC Copyright M.F. Sanner (March 2000) Compilation flags Surface CC TFLE.pdb, category main, probe radius 1.4, vertex density 2 22 connected surface components Total solvent excluded surface area = 10393.6 component areas = 8599.46, 624.842, 225.9, 216.153, 81.7059, 54.8894, 54.839, 48.0624, 45.9525, 43.9588, 41.5667, 39.1204, 38.7549, 37.0513, 35.5418, 33.6712, 32.9167, 28.9293, 27.8262, 27.7523, 27.7319, 26.9429 Total solvent accessible surface area = 10372 component areas = 9971.67, 202.012, 92.2225, 70.7414, 13.8165, 4.12717, 3.62753, 3.24856, 2.597, 1.1866, 1.72654, 1.33137, 1.08737, 0.962375, 0.64812, 0.231422, 0.40193, 0.120068, 0.0570046, 0.0515394, 0.0674059, 0.0311705 No SEQRES records for combination (#-2147483648.-2147483648) chain A; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain B; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain C; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain D; guessing terminii instead No SEQRES records for combination (#-2147483648.-2147483648) chain E; guessing terminii instead Chain-initial residues that are actual N terminii: #-2147483648.-2147483648 MET 27.A, #-2147483648.-2147483648 MET 27.B, #-2147483648.-2147483648 MET 27.C, #-2147483648.-2147483648 MET 27.D, #-2147483648.-2147483648 MET 27.E Chain-initial residues that are not actual N terminii: Chain-final residues that are actual C terminii: #-2147483648.-2147483648 TFLE 67.A, #-2147483648.-2147483648 TFLE 67.B, #-2147483648.-2147483648 TFLE 67.C, #-2147483648.-2147483648 TFLE 67.D, #-2147483648.-2147483648 TFLE 67.E Chain-final residues that are not actual C terminii: 424 hydrogen bonds Hydrogens added Charge model: AMBER ff12SB Assigning partial charges to residue TFLE+TFLE (net charge +0) with am1-bcc method Running ANTECHAMBER command: C:/Program Files/Chimera 1.8.1/bin/amber12/bin\antechamber -ek qm_theory='AM1', -i c:\users\haresh~1.pol\appdata\local\temp\tmpipssqi\ante.in.mol2 -fi mol2 -o c:\users\haresh~1.pol\appdata\local\temp\tmpipssqi\ante.out.mol2 -fo mol2 -c bcc -nc 0 -j 5 -s 2 (TFLE+TFLE) Cannot automatically determine charges for residue TFLE+TFLE; Run AddCharge tool manually to add charges and then rerun ESP Can someone please tell me a step by step procedure to make this work. Thanks & Regards, Haresh

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Re: [Chimera-users] Coloring map by curvature
by Tom Goddard 29 Jan '14

29 Jan '14

Hi Joel, I don't think surface curvature will be helpful understand the differences between two EM maps. But I was curious what it would look like. So here's a Python script and an image on a simulated map at 15 Angstroms. You use the script by opening your map, selecting the surface (ctrl-click on it), then open the curvature.py script (menu File / Open…). Here's a description of the method it uses from the comments at the top of the curvature.py file. # Color selected surface pieces by mean curvature. # # Gray at the average curvature value over the surface, and blue and red # at +/- 3 standard deviations of curvature values across the surface. # # The curvature is estimated from the vertices and normals of the triangulated # surface in simple way which will show artifacts from non-isotropic meshes. # For each triangle edge it computes the normal vector rotation from one vertex # to the other divided by the edge length. The vertex mean curvature is the # mean of the curvatures computed for each edge. # And the steps to make the example image open 1grl molmap #0 15 grid 2 model #1 select #1 open ~/Desktop/curvature.py Tom On Jan 29, 2014, at 9:40 AM, Joel Meyerson wrote: > Hi Darrell, > Thanks for the tip! I hadn't considered mesh lab but that link you sent looks promising. I'll also wait to see if Tom has any further suggestions. > Joel > > > On Wed, Jan 29, 2014 at 11:44 AM, Hurt, Darrell (NIH/NIAID) [E] wrote: > Hi Joel, > > I love Chimera and use it all the time. However, a quick-and-dirty solution to your problem might be to try Meshlab. It is kind of buggy software, but can be very useful. Here's a tutorial/blog entry that I found in a quick search. At the very least, it describes what I think Tom was communicating about enhancing surface shading: > http://meshlabstuff.blogspot.com/2010/03/mean-curvature-cavity-map-zbrush-a… > > FWIW, > Darrell > > -- > Darrell Hurt, Ph.D. > Section Head, Computational Biology > Bioinformatics and Computational Biosciences Branch (BCBB) > OCICB/OSMO/OD/NIAID/NIH > > 31 Center Drive, Room 3B62B, MSC 2135 > Bethesda, MD 20892-2135 > > > Disclaimer: The information in this e-mail and any of its attachments is confidential and may contain sensitive information. It should not be used by anyone who is not the original intended recipient. If you have received this e-mail in error please inform the sender and delete it from your mailbox or any other storage devices. National Institute of Allergy and Infectious Diseases shall not accept liability for any statements made that are sender's own and not expressly made on behalf of the NIAID by one of its representatives. > > From: <Meyerson>, "Joel [F] (NIH/NCI)" > Date: Tuesday, January 28, 2014 9:08 PM > To: Tom Goddard > Cc: "chimera-users(a)cgl.ucsf.edu List" <chimera-users(a)cgl.ucsf.edu> > > Subject: Re: [Chimera-users] Coloring map by curvature > > Hi Tom, > I have cryo-EM maps for two conformations of a protein, both in the 15 Angstrom resolution range. The conformations are visibly different, but I am also interested in seeing where they differ in terms of their surface curvature, as it could have bearing on how I interpret the conformations. If there's any other info I can provide just let me know. > Thanks! > Joel > > > On Tue, Jan 28, 2014 at 7:36 PM, Tom Goddard wrote: > Hi Joel, > > No, Chimera does not compute surface curvature. It would not be too hard to make a Python script that computed it and used it to color a surface. The main trouble is defining numerically the curvature for a triangulated surface at each vertex. Why are you interested in this? Is the idea to simulate ambient occlusion lighting where surface cavities are dark and projections are brighter? Is the idea to try it on EM maps or molecular surfaces? > > Tom > > > On Jan 28, 2014, at 2:29 PM, Joel Meyerson wrote: > > > Hi, > > Is it possible to color a map based on surface curvature? > > Thanks, > > Joel > > _______________________________________________ > > Chimera-users mailing list > > Chimera-users(a)cgl.ucsf.edu > > http://plato.cgl.ucsf.edu/mailman/listinfo/chimera-users > > >

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Coloring map by curvature
by Joel Meyerson 29 Jan '14

29 Jan '14

Hi, Is it possible to color a map based on surface curvature? Thanks, Joel

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adding GalNac moiety on Threonine residue
by Elsa Marquez 28 Jan '14

28 Jan '14

Hi there! Do you guys know if I can add or somehow draw a carbohydrate moiety such as GalNac to a single Threonine in a protein complex? Thanks! Elsa Marquez University of Alberta

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Surface Transparency Command Issues
by Joshua Carter 28 Jan '14

28 Jan '14

Hello, I'm having trouble getting the surface transparency command to work correctly. I'm currently making a movie about the formation of a protein complex and I want the subunits to be shown as ribbons while they dock and then after they dock the electrostatic surface to appear. I have the script written and the surface generated but when I use either the surftransp or transparency command nothing happens. The command is correct, if I use it to change the transparency of a ribbon or atom it does so, but if I try to make the surface appear after docking nothing changes. In addition, if I go to the Actions menu and change the surface transparency from there it also works. If you could help me figure out why the command won't work that would be extremely helpful. Thanks,Josh

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Re: [Chimera-users] Overlay structures in Chimera (UNCLASSIFIED)
by Elaine Meng 28 Jan '14

28 Jan '14

On Jan 28, 2014, at 9:45 AM, "Keasey, Sarah L CTR USARMY MEDCOM USAMRIID (US)" <sarah.l.keasey.ctr(a)mail.mil> wrote: > Elaine, > > I have a new question regarding overlaying structures using Chimera. > > I have opened two structures in Chimera. I am trying to move them so that they are overlaid. It appears as though I should be able to inactivate one of the structures in order to freely move the other, but this doesn't work for me and I'm not sure where I am going wrong. When I inactivate one structure, I can freely rotate the other, but not move it from one place to another. I have watched the youtube video here: http://www.youtube.com/watch?v=6VGYo1pRRZ8 which deals with merging two structures, and also watched the "Sequential Fitting" video on the "Videos" page of the UCSF Chimera site. > > Any suggestions for what I am doing wrong? I apologize for such elementary questions, I am a new Chimera user. > > Thanks in advance, > Sarah Keasey Hi Sarah, (we generally ask everyone to send questions to chimera-users(a)cgl.ucsf.edu, CC'd here, so that everybody can benefit, unless the data are private) Those videos aren't that relevant to your situation. More relevant is the manual page discussing the various ways to superimpose structures. The Chimera User's Guide can be searched or browsed from the Help menu, or you can see the same thing on our website, e.g.: <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/superposition.html> If using the mouse to move one structure, what you did is exactly correct: inactivate the other structure. The mouse should continue to work exactly the same for the movable structure as when everything was movable (both rotation and translation). The default control for XY-translation is middle mouse button, if you have one. For touchpad or mouse with fewer buttons, see here: <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/mouse.html> However, more often one doesn't use the tedious approach of trying to do it by hand, and instead uses one of the other superposition methods. The easiest is usually MatchMaker (in the menu under Tools… Structure Comparison), so I would try that first. <http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/matchmaker/matchm…> To help you become more familiar with Chimera, there are several tutorials in the User's Guide (again also available from Help menu), ranging from "getting started" to more advanced. <http://www.rbvi.ucsf.edu/chimera/current/docs/UsersGuide/frametut.html> I hope this helps, Elaine ---------- Elaine C. Meng, Ph.D. UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco

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Multialign Viewer Header Definition File (UNCLASSIFIED)
by Keasey, Sarah L CTR USARMY MEDCOM USAMRIID (US) 24 Jan '14

24 Jan '14

Classification: UNCLASSIFIED Caveats: NONE Hello, I would like to generate a Header Definition File to load in to Multialign Viewer. I am unclear on the format of the file though, I keep getting errors when I try to load the file in and I think it has something to do with the way I am formatting the file. Would you be able to provide an example Header Definition file? Thank you in advance, Sarah Keasey Graduate Student University of Maryland, Baltimore County ORISE participant, USAMRIID, Fort Detrick MD Classification: UNCLASSIFIED Caveats: NONE

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Segger : command line
by agnel-praveen.joseph＠stfc.ac.uk 24 Jan '14

24 Jan '14

Hi, I would like to automate watershed segmentation (Segger) on a set of volumes. Given that I have the details on the volume threshold, number of smoothing steps and minimum voxels in each region, is there a way to automate segmentation with different parameter inputs? Many Thanks. -- Scanned by iCritical.

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