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- Dose anyone know the most accurate instrument for detecting the platelet aggregation function?
Please recommend the better Instrument for detecting the platelet agrregation function
Why don't you visit http://www.globalthrombosis.com/?Following
- How can anyone calculate an electron beam plasma frequency?
Assume to have a relativistic electron beam. First of all, can the beam treated as an electron plasma? If yes, how its plasma frequency can be calculated? This electron beam has specified characteristics (total current, relativistic factor gamma) and it is confined under an external magnetic field.
Can anyone calculates the electron beam plasma frequency using the classical formula which involves the plasma density? And if yes, how in this case the electron number density can be calculated?
Any references will be appreciated.
What are you trying to do? Neglecting the B-field, the plasma frequency is essentially <v>/screening length, where <v> refers to the mean **RANDOM MOTION ** speed
It is related to screening effects
So sure you can calculate a plasma frequency. What are you going to use it for will determine whether you use it correctly or not.Following
- Could anybody refer which are the most reliable markers for the M1 and the M2 polarized macrophages?
Hello, i would like to know which are the most common and reliable markers, that can ensure me the polarization M1 or M2 of the macrophages i am going to isolate.
- How can I compute key point descriptor in SIFT features computation?
It will be helpful to me if you provide any good references to understand this.
The best reference would be the original paper I supose. But when you are looking into an actual implementation it may be time-consuming to develop it from scratch.
As already mentioned is the implementation in OpenCV a valuable way to go, or else look to http://robwhess.github.io/opensift/
Note however that SIFT is patented.Following
- How I can make core shell nanofiber?
I am working on PCL based nanofiber. I have to make core shell nano fiber using electrospinning unit. Please suggest me the way and other polymer or material to make these core shell nanofiber?
Thanks to all.Following
- Is it possible to formulate/standardize fast dissolving tablet of known intravenous route of administered drug?
Kindly answer as early as possible
Dear Jitendra Bhangale,
You mean to develop fast dissolving dosage form of a drug; which is presently given by IV route...Why not? But what's the rationale behind this? As fast dissolving tablets are meant for oral administration; make sure drug's stability through oral route and its performance...And as mentioned by others, you can use super disintegrants for this purpose...But focus on rationale.Following
- Does shredded cardboard confer benefits to soil?
I am looking for research that shows by adding clean, shredded kraft cardboard (ie no chemicals added, 100% cellulose) to a cracking clay soil, in combination with wood chips (50:50 basis), that it confers beneficial properties to the soil over and above than just adding wood chips on their own.
Any leads would be appreciated.
I suspect there could be some enhanced water holding capacity but am not able to prove that.
Some soil physical aspects of using paper products for soil improvement are investigated by the group of Christophe Schwartz in Nancy, France. It is not only about water holding capacity but also about compaction, settling, shrinking swelling, water repellency and so on
Literature: try e.g. this one: Sere, Geoffroy; Schwartz, Christophe; Ouvrard, Stephanie; et al.(2010) Early pedogenic evolution of constructed Technosols, JOURNAL OF SOILS AND SEDIMENTS 10(7): 1246-1254
- How can I optimise protein purification (protein with his-tag) (using complete his tag purification resin by ROCHE)?
I'm purifying a protein with his-tag (N terminal 6xHis) by using cOmplete his tag purification resin (ROCHE). I've tried several conditions but I can't seem to find the best way to purify the protein.
I know that part of the problem is that the resin I'm using now elutes the protein during 25-40mM Imidazole, but I still hope to find a way to optimise the purification.
This is how I'm purifying the protein now:
1. lyse the bacteria with buffer containing 15mM imidazole (pH8)
2. incubate the lysate(160mL) with cOmplete his tag purification resin(4~6mL) for 2 hours
3. load the resin+lysate into column
4. wash with the same buffer
5. wash with buffer containing 30mM imidazole (pH8)
6. elute with buffer containing 250mM imidazole (pH8)
The final result of the purification will be around 80%. (through SDS-PAGE, and the impurities bands are mainly at the bottom, around 10-17 kDa )
I tried using 25mM imidazole during the lyse process, however the protein just came right off when I tried to wash it for the first time.
I also tried using 40mM imidazole during the second wash process, but the loss of the protein was a bit too much.
So how can I optimise it? (without changing the resin I'm using now...)
And... because the impurities bands are mainly at the bottom... I was wondering... could it be that I let the bacteria induction process be too long so that some of the protein broke into little pieces and "happened to" have the his-tag as well?
It seems to me that you can on fact calculate the abundance of your protein in the extracts. We have had up to 30% of total proteins but I would accept 10% as very reasonable. Tweaking the conditions for induction might not improve that by a great amount, and if the amounts you are currently recovering are acceptable, probably not worth the time and effort. I would focus on the MEC. I usually check the column's efficiency using commercial proteins of the appropriate size.Following
- What are the different effects of length of data records in hydrological analysis?
From the frequency analysis, data and statistical analysis point of view. Is there any paper discussing about this matter
In some cases, if hydrological homogeneous time series data is rather short (example: less than 15 years), there are some mathematical statistical model softwares can help to users finding a fitting curve for hydrological analysis.
- I want to do Copper Electroplating on gold. The Cu thickness should be 8-12 micron with minimum roughness. Can anyone suggest a recipe?
Need copper electroplating on gold. The substrate is glass. area to be coated is 0.5cm^2.Following
- What happened here
Ok. I am going to look like a twit here but here goes nothing
I am trying to transform L. bulgaricus and L. Acidophilus with PLEM415, a e.coli-l.reuteri shuttle vector. contains amp and erythromycin resistance. I managed to transform the colonies through an electroporation method and got a large amount of transformants on the plates (8 ul/ml, confirmed it would only grow resistant bacteria through a control) Now I picked off a couple of colonies and propagated them on new plates, digested with pst1 enzyme and did a gel. But it looks strange. Pst1 is suppsed to cut the PLEM415 into two fragments, one at about 3,300 bp, the other just under 3000. In that image, from left to right, are e.coli, acidophilus and bulgaricus (twice). And the rest are badly visualized controls.. The e.,coli standard looks like it cut properly, the fragments match up, but the ones on the left, only one of them matches up, with the other being larger. I have no clue what happened here, It should have the plasmid.
Any ideas?, please be gentle, I'm an honors student and have only just startedFollowing
- Why do digital communications scholars say that the opposition of reality and virtual reality is a false dichotomy?
Farman (2012), p. 22 Why do digital communications scholars say that the opposition of reality and virtual reality is a false dichotomy?
Saying that virtual reality and reality are a dichotomy suggests that there is a clear and sharp distinction that separates reality and virtual reality, that something is either taking place in "reality reality" or in a virtual reality and there is no way that the too can overlap. In actuality, there are things about virtual reality that can also fall under the category of "reality reality" and vice versa.
For example, say you're in an online virtual world like Second Life where you are represented by an avatar. While you're there, you might meet another avatar and begin a conversation with that person. The interaction you had with that avatar took place in what would be considered a virtual world, but even though it wasn't a face-to-face interaction (or taking place in the "material sphere", as Farman calls it), doesn't mean the reaction was somehow "fake" or fantasized. You are not only embodied by your material self but also by your thoughts and words, and you can most certainly convey those thoughts and words through a virtual reality platform.
In the above example, there is clearly an overlap/grey area where something that took place in a virtual world could also be considered to have taken place in reality. Therefore the opposition of reality and virtual reality is not a strong one.Following
- How can I realize the hydrophilic functional groups in my carbon sample?
Are FTIR and XPS useful methods for this? I need to identify that on my carbonized sample there are hydrophillic groups like C=O, carboxylic bonds, etc.
My hydrophobic material has been converted to a hydrophilic material after carbonization and I need to provide evidence and reason for why this happened after carbonization.
What happened is very strange. Usually, carbonization produces a much less hydrophilic material as before, because many oxygen groups are released during pyrolysis. Observing the opposite makes me ask you what was the original material (a resin ?) and, importantly, what was the final temperature ? Did you carbonize under inert atmosphere ? If hydrophilicity increased, you should observed more oxygen indeed, and this can be done by FTIR. There is nothing to see on the FTIR spectrum of a normal carbon (as there are no surface functions !!), except if oxidized. You should mainly see C=O groups around 1750 cm-1. XPS will also confirm the presence of oxygen and suggests the surface groups to which it belongs. But I insist that there should not me more oxygen than before carbonization. If this is really so, it means that either your gas flow was very impure or, more surely, that you had a leak in the system, making air penetrate during carbonization. Or maybe also, you removed the sample from the oven when still hot, so it oxidized in air during cooling.
- What protocols are good/best for separating nuclear and cytoplasmic fractions in stem cells or cells with a large nuclei:cytoplasmic ratio?
I've been trying to fractionate glioblastoma stem cells (essentially transformed neural stem cells/progenitor cells) using either this Nature Methods protocol: Analysis of nuclear RNA interference in human cells by subcellular fractionation and Argonaute loading.
the NEB-PER kit: https://www.thermofisher.com/order/catalog/product/78833 supplemented with proteinase and phosphatase inhibitors.
I keep getting very pure nuclear fractions (no cytoplasmic or ER associated proteins) but my cytoplasmic fractions are always positive for Histone H3, but not PARP1 interestingly. I also get spliced GAPDH RNA only in the cytoplasmic fraction while I see 7SK nuclear RNA in both. I have either discovered that these cells secrete mini nuclei (possible but unlikely) or my fractionation is disrupting the nuclear membrane and letting nuclear proteins leak into the cytoplasm (more likely).
1. Ive tried centrifuging the cells to pellet them at very low speeds. I've used very dilute amounts of NP40 (0.01%), and higher or lower quantities of the CERI than suggested. I still get nuclear contamination.
2. The cells have very large nuclei, cell swelling in the hypotonic or CERI buffer isn't really apparent, the cells are larger but not prodigiously.
3. Ive tried washing the pellet a few times before proceeding to cell swelling. I don't know a good way to remove dead cells which may contaminate my cytoplasmic fraction.
While my fractionation was for looking at proteins rather than RNA, I've had a lot of success on a variety of cell lines (though not stem cells) using Angus Lamonds lab protocol - http://www.lamondlab.com/pdf/CellFractionation.pdf
Western blotting using Tubulin, GAPDH (cytoplasmic) or lamin B1, HNRNP proteins gave clean results.Following
- Does anyone know a good open source implementation of soft cascade classifier?
I'm searching for a open source implementation of a soft cascade classifier. Does anyone use or at least know a good one?
In the doppia framework of VISICS KULeuven (https://bitbucket.org/rodrigob/doppia) is an implementation of softcascade applied on Channel-Based detectors (ICF/Roerei). It is available for research purposes at my known.Following
- How do I aquire synthetic terpenoids for use in bioassays?
We are keen to acquire up to 1 mL of the following terpenoids for use in olfactometer bioassays with beetles and possibly in baits for use in field studies relating to pollination:
Does anyone have these compounds or know from where we could source them - and it a reasonable price? (USD5,000 per mL, the commercial rate for Beta-elemene, is prohibitive.) We would be interested in a collaboration with anyone who might be willing to supply standards gratis or at "mate's rates".
I would also suggest Sigma-AldrichFollowing
- Why can't I express my recombinant protein?
We are having trouble with several systems of recombinant proteins expression. Different plasmids (pET, pGEX, pRSET), in different cells (BL21 (DE3), HMS, bl21 STAR). All systems were functional before, but now none of them are producing.
We have assayed various IPTG source, water quality source, but have had no success. we have also verified the presence of plasmids.
Have anyone had any similar experience?
As Gaurav Kumar Singh has suggested before, try to obtain fresh recombinant expression cells by transforming the expression strain host with your plasmid again.
We have had the same problem several times and it was solved this wayFollowing
- We are looking for colleagues from India, Brazil, China and South Africa; сan you recommend anyone?
We are looking for colleagues from India, Brazil, China and South Africa, to apply for a grant for sociological and managerial sciences in Russia; сan you recommend anyone?
Hello, thank you for your answers. It is applying for a grant in Russia. Only those countries and South Africa: BRICS.Following
- How can I use Actor Network Theory?
Hi there I am considering using ANT theory for some research I am about to undertake, does it have to revolve around a particular project and event? And if so how recent does the project or event have to be to be relevant? I'm new to ANT and trying to grapple with the ins and outs!
Thanks so much for your detailed response! I am slowly piecing together the study but only so far as the literature review, sure it will be harder in the field. I will watch John Law's talk and read the resources you recommend. Thanks again, anything that helps with method will be much appreciated - as you say its only really alluded to in most of the literature as being 'ethnographic'
- What is Levenberg-Marquardt Algorithm? anyone can help me how to develop the data using ANN models and trained with Levenberg-Marquardt Algorithm?
when and why we are using Levenberg-Marquardt Algorithm in prediction? i need some tutorial for using Levenberg-Marquardt Algorithm.
thanks a lot Prof Felix L. :-)
WZ : something new for me makes me excited to find out more detail. im okay because im asking for who want answer my fundamental question. tq you for your little advice.Following
- How short of a time can you habituate animals after they arrive in the animal care facility?
We are conducting an experiment and were curious what is the shortest time we can habituate animals that have arrived in our animal care facility? We suspect that there is some influence in the ACF that is affecting our animals in our behavior experiments so we would like to use them as quickly as possible once they come in. I am aware from current literature that one week habituation prior to use is a common practice but we are curious if anyone has done less (ie 3-5 days)? Thank you for you in advance for you input.
In addition to Christiane and Jelena's advices, it depends on the animal species. Speaking about mice and rats, an acclimatisation period of one week in the new animal facility would be fine. During the acclimatisation period we just keep the animals in the cages and give them time to habituate the new environment without disturbing them. Of course it is important to know the housing conditions at the origin facility (did they keep the animals in open top cages and now you caged them in IVC cages). Speaking about habituation before behavioural studies I think that this is something different. You will need extra time no more than four to five days for handling and habituation of the animals to specific procedures depending on the behaviour test.Following
- What systems to record HRV/GSR and possibly other psychophysiological measures would you reccomend?
I'm looking for a simple system to record HRV, GSR and possibly EMG data. It should be possible to control it using python (with API) or at least with external triggers (serial, parallel). It should not be expensive.
What equipment do you use in your lab, and what would you reccomend?.
I'd be grateful for any suggestions.
- Can we attach viruses to micro beads?
All the work on virus attachment to magnetic beads has been done by attaching antibodies to the magnetic beads and then detecting viruses like Hepatitis-A, or norovirus? Is there a way to first attach a virus to a magnetic beads and then detect antigens in a sample?
An alternative would be purifying virus or virus-like particles, and biotinylating it (using something like pierce EZ-link sulpha-NHS-biotin) in vitro and then binding this to streptavidin beads. Or directly conjugating to cyanogen bromide beads. These would work fine for non-enveloped viruses, for enveloped viruses you may be better expressing the antigen recombinantlyFollowing
- Is there a way I can estimate the droplet size distribution or mean size of gas/liquid flowing in a pipe?
I have to do a simulation of multiphase gas flowing in a pipe that enters through a device, and that gas contains liquid as a disperse phase (as a mist), and for the particle injection in the simulation I need as an imput the size distribution or at least the mean size of the droplets. But the problem I'm facing is that I have no experimental/actual data and the droplet size is necesary for the simulation. The available data is: gas/liquid flow rate, temperature, pressure, gas/liquid viscosity and density, geometrical details of the pipe, liquid/gas surface tension. Thanks
The size and distribution of droplets depend strongly not only on properties of each phase but also on the way how they are produced. In case of atomizers you can use, as Zhuhu said, atomizer model, or, which is preferably, if you know geometrical details of the atomizer holes, conduct direct simulation of jet atomization (for example, OpenFOAM is good enough for that type of simulation). If droplets are produced by condensation, you can use one of the nucleation models with initial nuclei distribution which can be found in the literature (for some cases such distributions are close to lognormal).Following
- When investigating human behavior (for example, effect of attitude and norm on buying behavior), could r-square be as low as 0.5 or even less?
This is what some researchers suggest, and also some of my previous studies came up with results consistent with this notion. I will be glad to have some specific reference to this phenomenon. Any clue? Thanks
Whatever good statistical book has this information about R...ex Morris Hamburg, Agresti, Bayo laval, Glass Hopkins; Sharma, ....and also books about applied statistics to psycology.
If this is not helpuf, please tell me and i would be more precise (pages, ets..books...)
Have a nice time
- What is the basic principle of calcium frequency encoding signalling system that is used for calcium quantification in cells?
What is the basic principle of calcium frequency encoding signalling system that is used for calcium quantification in cells?
Thank you so much sirFollowing
- How can I extract or interpret lineaments and faults in a hilly area?
Please suggest some techniques or study material I can got through.
Below are the links of two papers on the related topic. Please go through. It might be of some help.Following
- Does anyone have any experience with Hygromycin B for selecting transduced cells?
I am trying to find out the suitable dose of hygromycin to kill non-transduced cell, but I am having difficulties finding it in LLC cells which are loosely attached and highly proliferating cell.Following
- Is 'Plasmocin™ by Invivogen' efficient to remove mycoplasma from virus stock?
It will be helpful if someone share their experience with plasmocin to remove mycoplasma from viruses. According to this article (https://www.researchgate.net/publication/232764995_Mycoplasma_removal_Simple_curative_methods_for_viral_supernatants) it is really efficient but however I saw some little contradictions in between 'plasmocin' and 'BM Cyclin'. That's why I need suggestions from your experiences, which one will be the best?
Your co-operation is highly appreciated.
yes plasmocin is effective. after 3-4 passage cycles you do observe negative test for mycoplasma by PCRFollowing
- What are decisive factors for determining the magnetic properties of the composites (diamagnetic film plus super-paramagnetic nanoparticles)?
Are sizes distribution and spatial separation of the nanoparticles the most important factors for determining the magnetic properties?
In general, superparamagnetic nanoparticles [ i.e < 30 nm ] with narrow size distribution will enhance the overall magnetization , in case of composites then the magnetization values will vary , which depends on magnetic nature of your composite, in case of diamagnetic film , the overall Magnetization will decrease if the nanoparticles were deeply encapsulated during film casting [ liquid film casting method] , also , proper dispersion of these nanoparticles is very important to maintain required spatial separation , because without the effect of surfactant , these nanoparticles [ especially at small size ] tends to agglomerate faster and create uneven dispersion during film casting . Hence , controlling size distribution , usage of proper surfactant is important along with spatial separation , these are important factors which decide overall magnetic properties of your composite, all the bset.Following