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If you have perform an in vitro transcription reaction, using a T7-RNA polymerase, the buffer/solution doesn't appear to contain any inhibitors or issues for translation. Why then must then the transcript-of-interest be purified before in vitro translation?
Many kits offer a coupled transcription/translation for plasmids containing a T7-promoter. This sounds advantageous since RNA is so short lived and many clean-up steps are eliminated. Why do I come across many protocols which emphasize mRNA cleanup and DNAse treatment? How do coupled transcription/translation reactions not have this same issue?
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The reason for separating transcription and translation in eukaryotic cell-free systems is the different optimum concentration of Mg for transcription and translation. Inside the cell, these processes are also separated in the nucleus and cytoplasm, each with their optimum conditions. So in cell-free coupled transcription/translation, you need to use conditions supporting both processes while not optimal for both steps. Purifying the mRNA helps to remove the by-products (mainly phosphates binding Mg) to avoid decreasing efficiency of the transation step, as stated above. In bacterial systems the translation is coupled anyway, so the cell-free system can be run in the same buffer conditions.
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I wanted to couple two simulations that are calculated separately like in-cylinder combustion and cylinder block, in your opinion can we map boundary conditions of the cylinder with block surface transiently? If yes which tool do you suggest?
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For this case, the use of multiple CFD programs can be useful, such as coupling the towing models with one program and meshing with the simulation using another program.
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A given state of vibration would have a dipole moment associated with it, owing to the inter-atomic separation. This would change when the molecule is excited, in accordance with the renewed separation. But I saw a dipole moment attributed to the very transition between these states. I am not quite able to get the physical meaning of it.
I came across this statement while going through an article on strong light-matter coupling in the vibrational regime. However, I believe the question itself belongs to the general context of vibrational excitations itself.
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Thank You Mike Albert The illustration indeed looks very intuitive.
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Here I am trying to calculate the Tc of material and electron-phonon coupling strength, but the Tc and lambda previously calculated are 14.1K and 1.1 respectively. So which parameters do I have to adjust to arrive at those values? One working with superconductivity DFT by quantum espresso can help me. here are my results attached.
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You can try to use the relationship given by the Eliashberg–McMillan relationship which is found in several textbooks, in that equation lambda and the function F are related. Probably you need to see if the ab initio program that you use calculates it. I guess so since you have lambda.
Kind Regards.
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For conjugated molecules with delocalized pi electrons, strong Raman scattering arises from their delocalized pi electrons and strong electron-phonon coupling.
What is the exactly physical meaning of electron-phonon coupling?
And what is the relationship between Raman scattering and electron-phonon coupling?
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I am now aiming to couple python with Transys but I failed what should I do?
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I think you can find the answer on web.. take a look at this (https://www.kankyoukei.com/en/2018/02/running-trnsys-from-python.html) ..all the best
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Please, in order to be able to analyze the mineral composition of an aqueous extract of plants in ICP , how can we prepare the samples? what are the steps to do the acid dissolution? choose solid acids (citric acid) or liquid acids (nitric acid)?
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The mixture of HNO3 and H2O2 looks the preferable for complete plants decomposition.
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Dear researcher,
I would like to understand better which are the most suitable tools to carry out pluvial flood simulation.
In particular, the interest is focused on the ones able to implement dual drainage models (coupling 1D drainage network and 2D overland flow).
Multiple commercial software can satisfy these requirements, such as Infoworks ICM or Mike+, but what about freeware/open source?
Any comment, suggestion or shared documentation is really precious.
All the best
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A very good (but not open source) software is FLO-2D. In addition to being able to model surface runoff it allows coupling of drainage system modeling to EPA-SWMM (open source). In addition, exchange flows on the water table (from top to bottom and vice versa) can also be modeled via coupling with MODFLOW.
Compared with HEC-RAS, it also allows only the zenith forcing to propagate the runoff and does not necessarily require an input hydrogram.
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Anyone know a good detailed tutorial on coupled integral equations in electromagnetics?
With detailed explanations how unknown entities are expanded into basis functions, followed by method of moments procedure (testing) and how the matrix equation is formed.
A 2D example - such as a double layered dielectric cylinder for example
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Hello,
I was wondering if someone can explain to me how to couple the light from a fiber into a waveguide on a chip.
Thank you in advance.
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Dear Dr Sewidan..I guess that you would like to couple from a conventional (monomode?) fiber to a dielectric ? waveguide on a chip (optical image line?)We may also discuss this via normal e-mail (Fritz Caspers@cern.ch
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Hi, i am trying to run HD and ST model with MIKE 3/21 Integrated Model for a coastal area for 1 year with 600 sec timestep interval but there is an abnormal error in the middle of the year. It's 'Blow-up elevation too large'. When I examine the result, there is an anormal elevation values (about 30000 meter) in some nearshore cells. So I changed the timestep interval, resolution but didnt worked. Also, when I runned only HD model, model worked without a problem. But when HD and ST run coupled, there was an error.
So if there is anyone who experience or knowlegde about this issue, can you help me?
Thank you.
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This is probably related to the calculation of the mesh elements when the ST module is activated, which means that you should check the resolution of the mesh in the near shore areas and try to decrease it.
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Dear researcher,
I would like to understand better which are the most suitable tools to carry out pluvial flood simulation.
In particular, the interest is focused on the ones able to implement dual drainage models (coupling 1D drainage network and 2D overland flow).
Multiple commercial software can satisfy these requirements, such as Infoworks ICM or Mike+, but what about freeware/open source?
Any comment, suggestion or shared documentation is really precious.
All the best
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Dear William F. Hansen thanks for your answer.
My question was more related to the numerical models available to carry out pluvial flood risk assessments, meaning software able to implement dual-drainage models.
Regards
PT
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i have a large nanoparticle (diameter of 16 nm) and I want to study its entrance through a lipid bilayer. i am running in NPT ensemble using GROMACS. However, for pressure coupling there are isotropic and semiisotropic options. The mdp documentation says that for semiisotropic coupling, the z is decoupled from the and y directions and is useful when simulating membranes. however, I tried both options.
the one with semiisotropic coupling, a huge change in the box dimensions in all directions occurred and this was because the nanoparticle penetrated the upper leaflet so the lipids moved away in both x and y directions increasing these dimensions which resulted in a decrease in the z direction.
the one with the isotropic coupling did not have a huge differences in the box dimensions.
attached are the images of both trials
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I think the semiisotropic would be the best choice in the case of the membrane, as mentioned in the documentation. If the box size didn't change with the entrance of the nanoparticle, the membrane pressure will be increased.
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How can we couple the RegCM regional climate model with another model (GCM or RCM or other)?
And how can we couple an Ocean model with RegCM?
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Hi,
For my curiosity, I downscaled an EMIC with RegCM 10 years ago. However, I don't keep that code with me now.
What did was investigating one of the recommended meteorological input to RegCM, for example NNRP, and then preparing your global output exactly like NNRP using CDO and NCO and run like NNRP input.
Hope this helps.
Cheers,
Kishore
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Hello,
I am dealing with error during lounching 2 Way FSI in ANSYS Workbench. Setup of the Fluent is ok (stand alone I am receiving expected results) and FEM uses Transient Structural.
Once I run the coupling I observe this error:
"Update failed for the Simulation compoment in System Coupling. The coupling service failed to start."
Please is here anyone who dealed with this error and was able to solve it?
Thank very much for your time.
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Thanks very much for your help!!!
Actually, I have checked my model several times, and still observed this error every times.
Finally, i used higher order version of workbench to calculate my model. I don't understand why, but it worked.
Thank you for your time.
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I am working on impact of a high speed metal particle on a substrate by FEA using Abaqus. The model is axisymmetric as shown in figure 1. I am using Coupled Euler- Lagrangian method for simulation. The substrate and particle is modeled as a Lagrangian body and the particle is placed in a Eulerian domain. I have created a discrete field for material assignment using volume fraction tool. The particle is then excluded from the simulation. The analysis procedure is Dynamics, temperature, explicit. The particle size is 25 microns. When I am using mesh size 1.5 microns for the particle, substrate and eulerian domain I am getting expected results as shown in animation1. But whenever I am changing the mesh size (increasing or decreasing) I am getting results as the particle is scattered or broken and impacting the substrate very randomly as shown in animation 2. Does anyone have ideas why this is happening?
The reference of the article I am using is
Xie, J., Nélias, D., Walter-Le Berre, H., Ogawa, K., and Ichikawa, Y. (October 1, 2015). "Simulation of the Cold Spray Particle Deposition Process." ASME. J. Tribol. October 2015; 137(4): 041101. https://doi.org/10.1115/1.4030257
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The volume fractions need to be updated after a mesh change. This is not associative.
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I am trying to solve coupled partial differential equation as given in the attachment, I was trying to solve it using the ode45 command of MatLab. but not getting any clue.
can someone help me with some references on how to solve these equations?
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MATLAB solvers only solve first order ODEs. If you would like to solve the system using MATLAB, you must rewrite the system of equations as exclusively first order. See the official MATLAB guide for more information on the solvers and how to rewrite your equations (https://uk.mathworks.com/help/matlab/math/choose-an-ode-solver.html).
Also, is this system overspecified (D.O.F>0)? I'm not sure...
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Sentaurus Device show “Exit due to failure”,what should i do?
this is my sdevice command
Math {
CNormPrint
Extrapolate
Notdamped=50
Iterations=15
ExitOnFailure
}
Solve {
*step1
coupled(Iterations=100){Poisson}
coupled(Iterations=100){Poisson Electron}
coupled(Iterations=100){Poisson Electron Hole}
*step2
Quasistationary (
InitialStep= 0.1 Increment= 1.5
MinStep= 1e-7 MaxStep= 0.2
Goal { Name="gate" Voltage= -0.2 }
Goal { Name="drain" Voltage= 0 }
){
Coupled{Poisson Electron Hole}
}
*step3
NewCurrentFile="IdVg"
Quasistationary (
InitialStep= 0.1 Increment= 1.5
MinStep= 1e-7 MaxStep= 0.2
Goal { Name="gate" Voltage= 0.8 }
){
Coupled {
Poisson Electron Hole
# eQuantumPotential hQuantumPotential
# eTemperature hTemperature Temperature
# Contact Circuit
}
CurrentPlot(Time=(Range=(0 1) Intervals=50))
}
}
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These are strongly depends upon structure or no of mesh elements. You can try by using a smaller value of initial step such as 0.001 and small increment such as 1.25
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Hello world,
I am trying to solve the non linear coupled differential equation which in mentioned
in figure attached. I will be grateful if anyone can help me with the problem.
Solve for U,V and W using MATLAB.
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Dear Amrit,
do I understand correctly that the first derivative of W is not appearing in the equations? So effectively the differential equations are only for U and V, and the problem of finding W is a "separate", different one. Is this interpretation correct?
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I am using M280 Tosyl-activated dynabeads for immunoprecipitation of a certain binding globulin from serum.
I have produced my own antibodies from hybridomas, which had been eluted with glycine and neutralised with Tris. I.e. the Ab solution contains Tris.
Would the presence of Tris adversely impact Ab coupling to the dynabeads?
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Hi,
Using Tris will add amine groups and possibly inactivate the functional tosyl groups on the beads. Typically, the amine containing buffers such as Tris can be used to block the remaining functional groups after Ab coupling.
kind regards
ketil
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Actually I am not able to understand that during the synthesis of a molecule if I do disconnection and try to make the molecule by cross coupling reaction then which part I should consider as aryl halide and which part as boronic ester in case Suzuki coupling.
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The aryl halide is the electrophile in the coupling reaction, so you should select the more electron-withdrawn partner as the halide, and the more electron-rich partner as the boronate (the nucleophile.)
This assumes that all four possible reactants are available at comparable expense. The coupling is reliable enough to let you choose on the basis of cost, which you might want to do if working on a large scale.
A good overview can be found at
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Please help me
If any mathematical equations for coupling of pmsm and pmsg in matlab?
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coupling equations available in ODEs and also built-on ode45, ode15, ect code in matlab.
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Hi every one
I want to simulate a array of patch antennas in CST. First I simulated a single element then I made array by array factor in the "farfield" part of CST and achieved desired response according to theory. then in order to model real conditions (mutual coupling and ...) I simulated array by exciting port simultaneously (in the "solver" part). Unfortunately the results are very different and do not approve each other . I don not know which response is correct? what can cause this huge difference? How can I know I simulated array in right way (specially in the second part )?
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I suggest you try simulating different size arrays and see if the results trend in the correct way. For instance you could try 2x1, 2x2, 3x1, 3x2, 3x3, and see how the results vary. When you can get the simple ones to give you expected results, then you can have confidence in the complicated ones. It is easy to make the mistake of exciting patches 180 degrees out of phase, for instance (by putting the feed on the other side - other people asking on ResearchGate have done that).
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when i run a nmr spin-spin coupling constant calc, all J values related to Se are zero. can someone explain why?
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The two most abundant isotopes of Selenium (78Se and 80Se) have spin = 0
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#Help post-
To all the #abaqus users and experts in #composite modeling & analysis field, I want your advice and help. On how to model and run Quasi-Static Indentation (QSI) analysis of a #hybridcomposite #laminate.
The laminate has 16 layers, each being 0.2 mm thick. All the layers can be glass fiber reinforced or carbon fiber reinforced. However, the stacking sequence is a bit unusual. Normally we're able to use #unidirectional fiber orientation in abaqus, but for this current project, it's #bidirectional. Also, because the hybridization is INTRAPLY, so putting different orientation angles in the same later is difficult, or at least I don't know how to model and analyze that. The stacking sequence and orientation angle are given below:
- Glass laminate [(±45)/(0,90)]4s, i.e.,[(±45)/(0,90)/(±45)/(0,90)/(±45)/(0,90)/(±45)/(0,90)/(0,90)/(±45)/(0,90)/(±45)/(0,90)/(±45)/(0,90)/(±45)]
here, both +45 and -45 degree orientation are in one layer, as well as the 0 and 90 degree in another layer. The photo might give a clearer idea. Also, is it a must to model the woven-like design of the composite in this case? or 3D Shell planar design would be enough (I don't think it's possible)? or 3D solid is needed? Do I have to use a #subroutine or python scripting?
Looking forward to have any input to go forward with my work. I'm really stuck here for a couple of days :(
#project #research #numericalanalysis #experiment #experimentation #simulations #analysis #compositestructures #QSI #orientationangle #stackingsequence
#glasslaminate #laminate #carbonfiber #glassfiber #compositeplate #model #compositematerials #compositemodel #FEA #finiteelementanalysis #FEM #finiteelementnethod #ANSYS #intraply #hybrid #hybridization #pythonscripting #abaqus
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It is better to use a multiscale modeling code such as TexGen4SC (https://cdmhub.org/resources/texgen4sc) to compute the effective properties of the woven layer and then treat is a homogeneous layer in your Abaqus simulation.
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I have formulated the mathematical equation of the vibration problem. The resulting equation is coupled nonlinear differential equation of 2nd order ODE. Please, anyone, suggest to me how to solve it using MATLAB.
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Dear Sandip,
to answer your question, I agree with Abdelghani: you have 1) to transform the 2nd order equations into 1st order ones and then 2) to use a MATLAB ode solver to numerically solve the resulting 1st order system.
To do step 1), you have to introduce new variables that correspond to first derivatives. For instance, let us say that you have a system of two 2nd order ODEs in x=x(t) and y=y(t), e.g. x''=f(t,x,y,x',y') and y''=g(t,x,y,x',y'). Then you can introduce two dummy variables X=x' and Y=y' (for example) and get a system of four 1st order ODEs: x'=X, X'=x''=f(...), y'=Y, Y'=y''=g(...).
Then, in order to apply step 2), you have to define a variable vector, say v=[x,X,y,Y], and a function, say myFun, that defines the system. In this case:
function vder = myFun(t,v)
vder(1)=v(2); % this equation corresponds to x'=X
vder(2)=f( t, v(1), v(3), v(2), v(4) ); % you should actually write your original equation for x''=X'=...
...etc...
end
Then, choose an ODE solver (for example ode45) and solve the system by using the basic command [t,v] = ode45(@myFun,tspan,v0); where tspan is an interval for the independent variable (e.g. tspan=[0,10]) and v0 is a vector containing the initial values for x, X=x', y, and Y=y'. So please notice that you must provide initial values for the first derivatives!
You can find more details about all this stuff here: https://www.mathworks.com/help/matlab/math/choose-an-ode-solver.html
Hope this helps! :-)
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I want to calculate the angle between C=O and C=C symmetric and asymmetric vibrating mode of phenol. I was trying to calculate by using DFT calculations but could not do it? please help.
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Vibrational modes involve all of the atoms in a molecule, not just a selected few bonds, and while C=O stretching modes tend to be relatively localized, C=C stretching modes tend to be less localized, often involve C-H motion, and will at a minimum involve multiple C=C bonds in the phenol molecule. Perhaps it would help to define more precisely what you mean by "the angle between the vibrating modes" and perhaps what question you are trying to answer with that information?
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I have some cell pellets that have been stored at -80C for a couple of months, and I'd like to make cell extracts of these to run in a human p53 ELISA.
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You may use RIPA lysis buffer supplemented with protease inhibitors to prepare the cell extract which is effective in extracting cytoplasmic, nuclear and membrane proteins. RIPA lysis extraction buffer contains non-ionic and ionic detergents ensuring efficient cell lysis and protein solubilization preventing protein degradation and interference with protein immunoreactivity and biological activity. Most antibodies and protein antigens are not adversely affected by the components of this solution. RIPA buffer-conducted protein extraction is compatible with various downstream assays including ELISA. RIPA buffer minimizes non-specific protein-binding interactions to keep background low.
You may use 0.5 mL RIPA Lysis Buffer per 5.0 x 10^6 cells.
RIPA lysis buffer recipe:
50mM Tris-HCL, pH 7.6
150mM NaCl
1% NP-40 or Triton X-100
0.5% Sodium deoxycholate
0.1% SDS
You may follow the protocol given below.
1. Resuspend the cell pellet in chilled PBS.
2. Centrifuge at 600xg for 5min.
3. Then carefully remove and discard the supernatant.
4. Add 0.5 mL of chilled RIPA lysis buffer to the cell pellet.
5. Vortex briefly. Incubate on ice for 30 minutes.
6. Centrifuge samples at 14000xg for 10 minutes.
7. Transfer supernatant to a new tube for ELISA.
You may aliquot supernatant (this is the soluble cell extract) to clean, chilled tubes on ice and store samples at -80°C for future use. Minimize freeze/thaw cycles.
Best.
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Dear Abaqus expert:
I am conducting fully coupled thermo-mechanical analyses with large viscoelastic deformation in Abaqus. The model works well in Cartesian coordinates. But when I extend to a spherical case, there comes a problem on setting up spatially variable body (gravity) force. For simplicity, I assume axisymmetry so that a 2D model is enough. Please see the attached figure for the modeling domain (a quarter sphere in gray).
For the interior of a planet (e.g., the Earth or Moon), the direction of gravity acceleration/force is expected to vary with space, all pointing to the center of the planet's sphere (i.e., red arrows pointing to the center C in the figure). So I need to impose a body force whose magnitude and direction vary with space. In addition, as the model considers large deformation (with Nlgeom on), the body force is required to be updated at every step.
I have searched and tested a few potential methods:
1) Wrote a python code to automatically add expected body force load for all the elements under *DLOAD. The model runs, but as you may expect: the body force always stays the same for the elements when they move. I would instead expect the body force changes with element coordinate, especially when the element/material deformation is significant.
2) Created analytical fields for the two components of body force, and then added them as body force load. The model can run but has the same problem as the previous method.
3) I have also read the reference to the user subroutine DLOAD. It seems to be helpful at the first glance, until when I recognize that there is only one output variable - load magnitude. As I need to vary two components of the body force, it can not directly satisfy my requirement.
I am wondering if anyone of you has encountered a similar problem, and may provide some insight? Any related suggestion would also be welcome and appreciated.
Actually, I have tried for a few weeks but still cannot find a satisfying solution. If there is anything unclear for you to understand my problem, I would be willing to add more details.
Thanks for your attention and best wishes,
Min
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Hi Min,
make a python script that reads the position of each node in your model, it calculates the distance from the node to the centre and, with that information, you can estimate the force components that you want to apply on each node and then apply the force to the node.
Using this approach, you should have no issue in solving a large deformation problem.
I hope it helps.
Federico
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The error message; "Trap current is insufficient" keeps appearing on the Shimadzu GC-MS QP 2010 instrument in my department over the last couple of weeks. When it shows up the MS stops running but the GC continues to run. The Shimadzu service agent has cleaned the iron source, cleaned the lens, etc and even changed some I.C boards, instrument was fine for a week and the error message reappeared. Is anyone conversant with this error message (kindly find photo attached) and how was the problem resolved permanently, please?
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I believe this problem is easy. The issue is that electrons are not arriving in the “trap” filament that identifies when electrons are arriving by the increase in current. It may be because the filaments have lost their resistance property or even because they are worn out by use, but it cannot be because they are misaligned, as they are fixed on pins, as they do not change position. The ideal is to clean the source, but check that the holes for electron passages between the filaments are aligned and not obstructed. In this way, part of the source needs to be rotated to align the holes and allow electrons to pass through. If that doesn't work, the ideal is to change the cables, filaments and test the plates, but turning the ion source and cleaning it is enough. Brazil
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Do someone know some strong counterions that are not perfluorated for reversed phase chromatography coupled to mass spectrometry ? We already used perfluoroheptanoic acid in a context of analytical set-up to separate polar compounds, but its use lead to interference in other analyses. The column used is HSST3 and has C18 silica beads but specific for polar compounds.
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Tara Louis that is a tough one because of the hydrophobic properties of the perfluorinated species. You could try to use the non-fluorinated components and increase the chain length of the ion pair builder (C8, C9) - not a big fan, and you will likely face ion suppression effects in the MS.
So, you are analyzing cationic species, that you would like to retain not using the HFBA. That speaks for small amines or amino components. What we did was use formic acid, but chose a more hydrophobic column. As a matter of fact, we chose a polymeric-based column, as the analytical challenge we faced was not the most complex one, and we could live with the significantly lower chromatographic efficiency. However, we used MS detection as well - I will copy a link to the technical report below, and it worked like a charme. Hence my suggestion is to go for non-fluorinated chemicals (better for the environment anyway), and choose a more "hydrophobic" column like a C30 modified. In other words, get the chromatographic resolution through the stationary phase, rather than through the ion pair reagent.
I hope this helps!
Good luck with your research!
Detlef.
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Dear fellow knowledge seekers.
I have a possibly quick question to ask to the IHC experts in here.
Following scenario, I have a couple of unperfused snap frozen brain tumors and I'd like to make slices on a cryostat from them and subsequently use them for IHC.
The question is, do I either cut the tissue directly at the cryostat and PFA fix the slices afterwards or do I thaw the sample and fix the tissue beforehand? The issue with the 2nd option could be that the tumor samples have a diameter of a fingernail so the PFA might not be able to penetrate the sample well enough then?
Anyways, I am grateful for any tips or hints you can give.
Cheers
Niklas
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PFA should be able to fix the tissue. you could also fix before you cryosection that way you could do both cryosectioning and IHC. It is also possible that you may be try dropping the cry tissue block in PFA so that as it melts, it is already coming into contact with the PFA. Ia m not sure if things like OTC will dissolve in PFA like it does in water. I would then transfer the tissue to fresh fixative once it has thawed and then proceed with the IHC.
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The glass wool in packed liners from the manufacturer is moving after a couple weeks of injections on the GC-FID. It is only happening on one out of the 6 GC systems. One cause for this that I was told is that the glass wool packing may be inconsistent, but this doesn't seem likely since the other instruments are ok. The other thing I have been told is that the split vent trap may be plugged and therefore causing back pressure and the wool to move. Does any of these sound plausible or do you have any other solutions? I prefer not to pack them in house. Thanks.
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- Check your septum. Leakage in the septum may cause glass wool to move during needle exit.
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Energy Policy @ Local and Global Scales: Are they same or different?
With China and India alone would account for nearly 40% of Global GDP in the next couple of decades, whether the current and future policies relating to energy demand and supply at the local-scale (in China and India explicitly) will get along with the global targets, while maintaining the air-quality and enhancing the energy efficiency – by reducing its dependence on coal and limiting the fuel consumption and by expanding the renewable electricity?
OR
The energy balance would change further, when Indian Population exceeds Chinese Population – in the next few years?
Whether the continual increase in global population (nearing 10 billion in the next couple of decades) with a declining Chinese Population (say, from 2026) will have any major impact on global energy policies?
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India MUST also act similar to China!
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hello
I want to calculate the molar mass of polyvinyl alcool 10% weight coupled with imino di acetic acid
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Dear Hajar Benrzeil, you can get it either from the supplier of the product or get it experimentally via conventional techniques such as viscometry and GPC. My Regards
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We are recoding our data and transforming the data values into the values we won't according to the questionaries we have used and its scores.
The first couples of recodes went fine, and we can see the values in the Data view after we ran the syntax. But then all of a sudden after we ran a recode of the next variable in our syntax, the value did not show in the Data view, and instead of the value, the columns just have a dot; .
We don't have any missing values, and the original data, we are recoding, has values. So what are we doing wrong, can any body help us?
We have been checking the syntax over and over again, to see if we are doing something diffrent form the first couples of recodes, where nothing is wrong.. but we can't find any differences.
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I have been facing the same challenges , figured others out but some still giving me problems and i have checked over and over, but still get missing system when I analyse.
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I noticed that the number of questions, which remains unanswered, quickly increases for the last couple years. Such unanswered questions are commonly unprofessional, badly formulated and meaningless. Often, they do not have minimal necessary information. Misspelling and use “street English” are common. If I read such posts, I would not respond. A long time ago, there was an option to down-vote questions. How to improve the quality of questions/discussions and to discourage valueless posts. What is your opinion?
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Yurii V Geletii Yes, that is a good point but also it might be the case that the question does not lie within the competence or interest of most people. Richard
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I wonder if anyone could provide me a detailed protocol or related publication for DNA Laddering (for cell lines). I know there are a couple of questions about it here, and reviews are diverse and little specific regarding concentrations and steps.
Thanks in advance
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Good
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I already define 6 coupling constraints 3 in each end, first one with master point (centroid of web) and slave nodes are the rest points of the web with constrained DOF (U1,U2,U3,UR1,UR3), the two other constraints are in 2 flanges with master nodes (centroid of flange) and slave nodes are the rest nodes of the flange. My BCs are simply supported (u1,u2,u3,ur1) in one end at the centroid point of the web and (u2,u3,ur1) in the other end.
when applying NL analysis using static riks after applying imperfection, I got a convergence problem from the first increament .
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hi,
kindly refer this link:
Best wishes..
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Dear Researchers.
I am performing some fluid structure interaction using ANSYS coupled system.
I know that using Coupled system GUI is set automatically to 2 processors and this result in a very very long time for resolving just one problem.
Can any one guide me step by step on how to resolve the issue please!
I will highly appreciate your feedback.
with the best regards
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Ren Songbo The original method does not work and even using the intrinsic FSI does not work for this type of problem, the solution diverges from the targeted results even with very careful parameters.
The 1-way FSI gives good results so that what encourages me to pursue two-way FSI in order to get a better image
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I am stuck in problem, it may be silly but if someone could guide would be great. I am looking to transform and plot a feature but it gives me the below error
> hist(da1$Inc)
> hist(da1$log.Inc)
Error in hist.default(da1$log.Inc) : 'x' must be numeric
>
I read couple of blogs and help pages which indicates that variable should be converted to numeric but the data is already numeric and am able to plot histogram & calculate summary stats. So unable to figure out what should be done. I want to visualize transformed data and then feed it to the model. Could someone please help. Thanks in advance.
Regards
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Dan Li, Histogram always takes numeric data. Pls, check if the data type in R has not been converted to factor or character. Change the variable to numeric
data$x=as.numeric(data$x)
Best!!
AN
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Greeting fellow researchers,
I am working on a Simulink model in Phasor mode. I want to analyze the effect of capacitive coupling in the electrical network for which I inject a current source in the system at different line lengths and observe the bus voltages prior to connecting any machines. For the current sources, I define the frequency as slightly different than 50Hz to observe its interaction with the network and the possible resulting disturbances. However, when I run the simulation I get the following error:
"There is no voltage source, current source, or machine block with a frequency matching the Phasor simulation frequency."
I tried to run the simulation in continuous mode to avoid this error but then I receive a completely different one:
"Unable to perform assignment because the left and right sides have a different number of elements."
I would be grateful if anyone can guide me in this regard, where I am making mistake in the analysis, or perhaps a solution to the above-mentioned errors.
Regards,
Yasir Shamim
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Marcel Nicola, thank you for the model suggestion. As I understand from the MathWorks documentation, to model the Capacitive coupling effect, I have to use the "Transmission Line" block instead of this one.
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I want to know which method gives the more accurate result if we compare between between direct and sequential coupling of thermo-mechanical stress in ABAQUS and why? If possible please attach some relevant theoretical material.
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Dear Pardeep Kumar, I still recommend referring to the links I have sent you. However, check the link below. It's an article that could give you useful information. Worth a look.
Best regards.
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I have an array configuration with 9 antenna element. Can you please tell me what is inter and intra coupling and how could I find it in CST simulator software.
Thank You.
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Hi
I am working on array antenna for a while but until now had not heard inter and intra coupling. After searching I could find just 3 documents that explain this subject. take a glance at these:
Futuristic Communication and Network Technologies(page 762)
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Is it necessary to go through the conventional Gram stain, optochin, and bile solubility test after isolating my pneumococci on selective media if my intention is to identify the isolates by MALDI-TOF MS? The sensitivity from the couple of studies I read is quite high.
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Hi Reuben,
Yes, you can identify S. pneumoniae using MALDI-TOF biotyping, for instance, with MALDI Biotyper from Bruker Daltonics.
You may have a look to the following:
You may go through conventional microbiological methods for characterization of your isolates in paralel, but identification by MALDI-TOF MS alone is reliable.
Hope this helps, good luck.
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Ran into a problem when performing coupling with DCC. The complex made with DCC doesn't continue reacting with the amino acid, and the yield is standing at about 50%. how to break up the complex and get my yield increased, or is that as much as I can get?
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1 eq. of 3 - nitro benzoic acid, 1 eq. of 4 methoxy aniline, 1.2 eq DCC, and 1 eq of TEA, in THF room temperature. doing reaction without HOBt as in my understanding it's an initiator for complex forming with amine part, which is already happening. Reaction is performed with 10 grams of starting material.
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Hello, I'm a graduate students at the University of Ulsan, South Korea.
I want to synthesize a branched-peptide by coupling this peptide sequence: Ferrocene-FFKY and G-FLAG-tag (DYKDDDDKG). At first, I used HBTU/DIPEA in DMF for coupling them, but it didn't work (checked by HPLC). So, does anyone can help me by suggesting any other method or give explanation of why it didn't work?
(what I meant by "it didn't work" is on HPLC the product's molecular weight peak didn't showed (it should be 1867.77). However, an unknown MW peak is showing (1521.9))
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You have too many options for amide bond formation, assuming that is what you are attempting. The epsilon amine of the ferrocene-peptide lysine can bind to any of the aspartic acid residues on the G-flag tag peptide. There is also a lysine on the G-Flag peptide that is able to bond with the C-terminus of the ferrocene peptide. I'm assuming here that both peptides are N-terminally labeled. Furthermore, the lysine on the G Flag peptide can form a ring with any of the D residues on the same peptide. if you aren't blocking the D residues or C-termini, and at least one of the lysine amines, you are going to get mixed results. if you don't need a peptide bond, then I would try EDC with appropriately blocked peptides.
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Hello there,
I am designing an antenna array to be used ONLY IN RECEPTION for a geolocalisation sensor. So, i was wondering if coupling effects would have impacts on the rceived signal strength or phase.
Thank you!
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I would like to add to the colleague Sovan Mohanty , that you speak about near field coupling or the mutual coupling. In fact the antenna array must be built such that its elements are ideally isolated from each other so that the mutual coupling vanishes. It they are coupled with each other then there will be signal flow between each other specially from the neighboring elements.
To reduce the coupling one has to keep the adjacent elements sufficiently faraway from each other. There are also other means to isolate the antennas from each other.
For more information you can follow the paper in the link:
Best wishes
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I am working with some molecules having benzotrifluoride and fluorobenzene. In the C13 NMR, some couplings are seen. If you have any good paper on the Carbon-Fluorine coupling and coupling constant, please share it with me. It will be appreciated.
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This is always the first place I look
If you go to fluorobenzene (13C) you will see there is coupling to all the carbon positions.
Note these are spectra are quite old and consequently at a very low frequency so on a modern instrument (at higher field) some of the smaller couplings may be not be resolved.
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Perception-Action Coupling Theory - What time period encompasses the action?
Nowadays science considers perception and action to be coupled as opposed to being independant phenomena.
1. Many affiliated media use the expression of being in the present. Pointing to the perception of an actual moment. But how long is that moment? Within a second there are 1000 actual moments and in each one of them 1000 actual moments occur as well.
2. The explanatory model of all motoric movement actions theorises that a perception of such a short actual moment solely gets its context due the fact of ADJACENT (!) perceptual images of past (manifest) actual positions P and perceptual images of future (latent) actual positions P of f.e. a moving ball. Isn't that in a nutshell the perception-action coupling theory?
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I'd offer the possibility that perception and action shape each other at multiple time scales. This point is testable in different ways, including hierarchical linear modeling as well as fractal and multifractal modeling. There are limits due to the scale dependencies of physiology and of the contextual constraints, but so far, there is no need for a limit on the time scales possibly implicated. Within whatever bounds you could find, there is the potential for continuous variation of time scale, as well as the evidence that multiple time scales of perceptual-motor coordiantion interact, either potential implications again at several time scales-originally involved or not.
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Hello, I am working with FSI simulation of a rotor blade using Ansys Workbench 19.2, where transient structural and fluent solved with system coupling. My simulation is working fine when I consider the blade made of steel or aluminum. But, if I consider fiber epoxy composite, then the system coupling failed to update. The error is" The value of UX at node 18556 is 1.061435247E+11. It is greater than the current limit of 1000000". Sometimes I got another error, "Update failed, negative cell volume detected" N.B. I have turned the large deflection on in transient structural solver control. And the simulation worked with fiber epoxy composite for lower angle of attack. That means, it is not working for high-speed flow, higher angle of attack and soft material.
Please help!
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Hi,
I know this is a late response but I think it will be helpful for future researchers.
The solvers are not stable sometimes when you use a softer material. You might be able to fix it using the Quazi-Newtonian algorithm. There you will not be able to use system coupling. So the coordination part will be done by the Command prompt (Windows).
the following tutorial will help. Please note that you will have to access it through ANSYS help only.
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Hello
I have this frame where the supports are at the column end and I want to calculate the axial forces in the beam or the connection.
I defined RP, coupled the surface I want to calculate with it, and defined a new output field and history for the RP set, but yet all the result I got is zero from the reactions at this set.
how can I get the axial forces?
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Another approach is to insert connector element (type BEAM) between joining parts and request output variable CTF.
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I follow this protocol for antibody conjugation
1. 0.5g CNbr-activated sepharose 4b swollen by 0.1M Hcl
2. washed by 50ml 0.1M Hcl (I used centrifugation and suction)
3. washed by 6ml of coupling buffer (0.1M NaHCo3, 0.5M NaCl) pH8.0
4. conjugate 10ml antibody (1mg/ml), Room temperature, 2h, in rotator
5. washing 3 times with coupling buffer
6. blocking with 1M Tris-Hcl pH8.8 buffer, Room temperature, 2h, in rotator
7. washing 4 times used to coupling buffer and low pH buffer (0.1M acetic acid, 0.5M NaCl)
then i tried to protein purification
1. washed column by lysis buffer
2. load lysate from E.coli
3. washed by 0.1M Tris-Hcl pH8.0
4. elution (Glycine-Hcl pH3.0)
the problem is that after elution step, i got protein with antibody.
why antibody eluted with protein? I know that CNbr conjugation is covalent bonding with antibody. so antibody can`t eluted in this situation... but why???
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CNBr sepharose does not provide a completely irreversible link, though I imagine what you are seeing here is actually non-covalently bound antibody.
The best thing you can do, assuming that your antibody will tolerate it, is to wash the column before use with the glycine elution buffer and then re-equilibrate. The second run of the column is used to purify the antigen. In theory, any loosely bound antibody will have been removed in the first run.
If you are still having issues, try to saturate the column with antigen so that the ratio of desorbed antibody to antigen is at a minimum.
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I am quite familiar with EIS and have used it on a number of systems, but I feel like there is not discrete discussion in literature on certain topics that are taken for granted. For example, in a 3 electrode cell (Ag/AgCl reference, Pt counter, and graphite working electrode) with a varying concentration of NaCl(aq), we see a semi-circle capacitance in parallel with the solution resistance, we know this is the solution resistance because it follows the expected trend of decreasing as a function of concentration increase. We also know in this system there is no charge transfer from the electrode to solution since there is no electrode dissolution here.
I do not have a problem with that explanation, the idea that solution resistance is the tailing edge (low freq) of the semi-circle instead of always being the leading (high freq) edge of the semi-circle as some people would claim is outlined nicely in this paper:
Article Physical Interpretations of Electrochemical Impedance Spectr...
But we would still conclude that the capacitance of the semi-circle seen here is the debye double layer capacitance formed from the ion migration to the graphite electrode. This makes sense in that we expect this physical process to happen, but it does not make sense to couple this with the solution resistance in my head. If the capacitance is formed in the thin insulating layer between the graphite and ions, how can the bulk solution resistance be coupled with this? It seems that these two processes should be in series instead, there is no scenario i can imagine where current has a choice to either flow through the debye layer OR the bulk solution, it seems like it would always be both in this case.
So this leads to the question, is there another form of capacitance present here? What are the possible capacitive processes in a simple inert electrolyte in graphite? Could it possibly be water uptake into the graphite like what we see with coating layers?
In general i feel we are too quick to label things with physical processes in EIS without questioning it, and i wanted to have a discussion of the possibilities here
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can you show, please, any EIS plot(s) with, at least, two extreme[1] concentrations of the NaCl ?
1. A (very) low and a (very) high NaCl(aq) concentrations.
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Hi,
I am doing a fully coupled simulation for heat generation inside rubber composite. (fully coupled = solving the mechanical and heat transfer constitutive equations simultaneously ).
The following points were used:
1. 2d-axisymmetric study (we have a cylindrical sample).
2. hyperviscoelastic model (Mooney Rivlin two parameters, relaxation times, and energy factors were evaluated from experiments with the optimization module).
3. force-displacement loops and dissipated energy agree with the experiment.
I defined the heat source as stresss*train*frequency (harmonic heat source).
My problem is that when the temperature reaches equilibrium, it decreases with time instead of staying constant or oscillating around a constant value. This decrement increases with the frequency. The used frequency are 10, 20, 30, 40, and 50Hz.
The attached figure shows a comparison between the experiment and simulation.
I don't know if this is the regular case for a harmonic heat source, or do I have some problems with time-stepping or solver??
The simulation was performed using Comosl Multiphysics.
Thanks in advance for your help.
Regards,
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Dear Mr. Thomas Cuff ,
Now it is perfect.
Thank you so much......
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Please see the attached plot of this type for your reference. How to plot M-R curves by solving a coupled ordinary differential equations using "NDSolve" package?
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which code is used to plot these graphs, they look very intriguing ...
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I want to arrive at a mathematical expression finding the natural frequency of two parallel beams connected by a coupling beam at some location. Is there any helpful theory/literature/approach to get it.
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Dear Bollapragada,
Please check out the following paper:
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I have a beam that I was simulating in ABAQUS/CAE.I came across an interesting phenomenon. It worked when I linked the reference point and applied the boundary conditions to it, which is clear, but it did not work when I applied the boundary conditions to the geometric region and left the coupling alone (to get the reaction force only). Due to several constraints, I'd want to obtain the reaction force as a single curve rather than the tiresome task of adding all the reference nodes and plotting it. It's a quarter-symmetrical model, and coupling isn't an option for me when it comes to applying boundary constraints. I'd want to take a single curve of reaction force from the output and use it in a Manticarlo simulation with a data matching component. To conclude, providing boundary conditions to the partition below the face does not help in the post-processing of a single response force curve, but activating the coupling automatically deactivates the boundary conditions.
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I wish you all the best I apologize that this is not my specialty
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I applied a vertical force on a reference point which is coupled to apart of my model in Abaqus Standard. But surprisingly, the vertical reaction force output is slighlty different from the applied vertical force on the reference point! Could anyone suggest a reason for this discrepancy!?
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Mohammad Reza Mansouri Can you share your Abaqus model (.inp)?
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I am going to couple anaerobic digestion model no.1 (ADM1) with CFD modelling. I need some data for validation. Where or in which research paper can I find those?
Is it necessary to validate the coupled CFD-ADM1 or the validation of CFD part is sufficient?
Best regards
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Check out my articles, you might benefit from them
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One of the most valuable properties that allows the 1H-NMR spectrum to give structural information is spin-spin coupling, which is caused by spin coupling between hydrogen nuclei that are not chemically identical. Different spin states interact through chemical bonds in a molecule to give rise to this coupling, which occurs when a nucleus being examined is disturbed or influenced by a nearby nuclear spin. In 1H-NMR spectra, this effect is shown through peak splitting that can give direct information concerning the connectivity of atoms in a molecule.
My question is, in which case would this coupling not occur, despite the symmetry?
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Dear prof.,
Please take a look for the reference below.
Abragam, The Principles of Nuclear Magnetism, Oxford University Press2006.
Regards
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Hi everyone,
I am wondering if I can neglect DDSDDT definition in UMAT, for a coupled thermal-structural analysis?
I have defined DDSDDE, RPL, DRPLDT and DRPLDE.
Since, the accuracy of DDSDDT could just affect the convergence, not the final results, I am eager to know if I can totally eliminate DDSDDT definition in my routine code?
thanks for any helpful comment
Pejman
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There are two cases that I can think of where you could set the partial dericative of stress with respect to the temperature, i.e., DDSDDT, equal to zero:
1. when the coefficient of thermal expansion of the material could be considered almost zero and the material doesn't produce or absorb any latent heat or
2. the respective partial derivatives of the material model equations seem to be negligible when considering various sets of representative values.
Regards,
Anargyros
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Can some one guide me to some basic literature about designing inductively coupled RF discharge (preferably cylindrical). How to decide the diameter, number of turns, frequency, power, gas pressure etc. Rule of thumbs would also work if exact literature is not available. Oh yes and in presence of high external magnetic field.
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The books of Pascal Chabert and Lieberman are the primary references, of course, but in addition to that this might help :
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Hello everyone
2-3 months I start getting weird XRD diffractograms. I was performing locked couple analysys on some polycrsitalline films. I am analysing those films for years so I know them quite well-. I am interested in some stress measurements so I was focusing on some Locked coupled spectra. This time I got peaks with huge intensities for a certain theta positions. I start analysing only the substrates and the peak are still there (mgO and Quartz - see the pictures; I get same results for Si or Al2O3 substtrates). Moreover, I performed LC on the empty sample holder (that should be zero background) and surprise the peaks are still there. It might be a contamination but the FHWM lead to very crystalline phases. It seems to be Aluminium or Titanium. Any idea about the sources of this peaks? Any solution. I had same problem 5 6 years ago on the same machine but that dissapeared by itself after a while. Now the problem is lasting.
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This is a very interesting problem. Let me begin with the basics. After collimation, there is a diffraction parallelogram: all that you "see" in the diffraction pattern must be "touched" by the diffraction parallelogram. If collimation is too large, also the diffraction parallelogram volume is. Can you minimize the collimation? Can you move the "focus" of the diffraction beam?
For the moment these are my first suggestions.
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Dear all,
I am trying to optimize my panels for our confocal laser microscopy experiments and with our available laser/filter setup, it would be great to have antibodies/Streptavidin that would be coupled to a fluorochrome with a more or less narrow excitation around 488nm and a emission wavelength around 605nm or longer. It might be wishful thinking, but does anyone know any fitting (new?) colors that would be useful?
Thanks for your efforts & best wishes,
Urs
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Hi: It's an "old" fluorophore, but you could try DCM - https://omlc.org/spectra/PhotochemCAD/html/038.html - excitation max ~490 and peak emission ~620 nm (in methanol). Because it's a laser dye it is very stable.
This book - https://www.chem.ucla.edu/~craigim/pdfmanuals/catalogs/Lamdachrome-laser-dyes.pdf seems to be out of print now but contains a lot of good information on laser dyes (fluorophores used in tunable dye lasers). You might be able to find another suitable molecule there?
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Dear All. I have separated 38 amino acids on HILIC column couple to QQQ followed by using 10 isotope-labeled amino acids as internal standard. However, I am not sure which formula to use to calculate the concentration of my amino acids. Can you help me out? There several formal out in literature I not sure which is one is best????
Thanks ...
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I would like to highlight a couple of amino acids which are close to each other. While the chain of the protein is at the background. I mean like the cartoon was in the second plane?
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Hello, Gabriela,
If I understand your question correctly, you should do the following:
1) Open your protein in a cartoon view
2) Click Tools - Sequence - Sequence.This will open a separate window with amino acid sequence of your protein.
3) Select in this window particular residues you are interested in. Use the cursor with the Shift key pressed to keep the previous selection.
4) Then you can visualize the selected residues in different ways. E.g., click Actions - Atoms/Bonds - side chain/base - show.
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I understand that inductively coupled plasma (ICP) means inductively coupled plasma, which has coils around the dielectric wall, and reactive ion etching (RIE) uses combination of chemical and physical etching. I am trying to understand different etching techniques and I have some confusion.
Does the term ICP and CCP (capacitively couple plasma) refer to the structure of the hardware where as RIE refers to the etching mechanism? So for example, could RIE be done with both ICP and CCP (ICP-RIE or CCP-RIE)? Or Could RIE be done with only ICP?
The ICP etcher I have access to has two RF sources. So I can set RF power 1 and RF power 2 on the recipe. What are the two different RF power sources?
Please let me know if there is a good resource I can use to learn more about etching. I am having hard time finding a good resource.
Thanks!
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Reactive-ion etching (RIE) is an etching technology used in microfabrication. RIE is a type of dry etching which has different characteristics than wet etching. RIE uses chemically reactive plasma to remove material deposited on wafers. The plasma is generated under low pressure (vacuum) by an electromagnetic field. High-energy ions from the plasma attack the wafer surface and react with it producing anisotropic etching preferable in the direction of the ions.
Different types of RIE systems exist, including inductively coupled plasma (ICP) RIE. In this type of system, the plasma is generated with a radio frequency (RF) powered magnetic field. Very high plasma densities can be achieved, though etch profiles tend to be more isotropic.
A combination of parallel plate and inductively coupled plasma RIE is also possible. In this system, the ICP is employed as a high density source of ions which increases the etch rate, whereas a separate RF bias is applied to the substrate (silicon wafer) to create directional electric fields near the substrate to achieve even more anisotropic etch profiles.
An inductively coupled plasma (ICP) or transformer coupled plasma (TCP) is a type of plasma source in which the energy is supplied by electric currents which are produced by electromagnetic induction, that is, by time-varying magnetic fields. So it is a part of the RIE system.
Hope this helps. Best regards.
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I have seen a couple of panel data research where the authors fill up missing data of a variable with similar variable from another source. For example , getting inequality data from WDI and filling the missing values up with data from SWIID. Is there any justification for this and also how do we fill this up when the 2 estimates are Calculated differently and with different scales.
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Dear Humid.
The use of interpolation is better than filling missing data from one source with another source. The units and other conditions surrounding the data collection is different.
However, you can make use of proxy, that is using other close related variables to proxy the missing variables as a whole.
Regards
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