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  • Sophie Chattington added an answer in Pest Management:
    Has anyone a good technique for handling single Trichogramma in the lab?

    I am moving single trichogramma around (for sexing, mother-son mating, experiments etc), and have experimented with just waiting for them to climb up small tubes (but then it can be hard to get them out again), using an eyelash, or an aspirator (but this is proving not optimal, the one I made anyway)... what is everyones experiences, and anyone found an effective, and time-saving, technique? 

    Many thanks in advance!

    Sophie Chattington

    Hi, I have had a look in this paper, but cannot see anything about techniques for individually handling the wasps? Only that they did... ?

    Many thanks

  • Dmytriy Mykhailov asked a question in Speaking:
    How can You describe the concept of modes of existence created by Bruno Latour in his last research?

    Working with the last book of Bruno Latour I've found an interesting interpretation of existence through a multiplicity of its modes. But I can't catch up what directly Latour means using collocation "modes of existence". Frankly speaking the number of this modes is a secret for me as well. Hope for your help.

  • Liu Yuanhui added an answer in siRNA:
    Do you know about the siRNA knockdown efficency 30%, how can i make it better?

    I transfected the clathrin siRNA at 20nM and 50nM for 2 to 6 days, then lysed the cells, then did the western blot.  The image is in the attached annex. The best kncokdown efficiency I can reached is 70%, but how can I make the efficiency better? Thanks very much!

    Liu Yuanhui

    Okey, I will disccus this with my director and try to design it by ourselves. We did use the Lipofectamine reagent. Thanks!

  • Shiuh-Hwa Shyu added an answer in OpenFOAM:
    One model for different Reynlods numbers?

    using openFoam, I have to compare the behaviour of the fluid inside a pipe flow at different speeds, that ranges from laminar to Turbulent flow. The problem here is that I need to stick to one model, because different models behave differently, which results in showing sudden drops in the curves. At the same time, one model is not valid for a such a range of Reynolds number. For example I think I would rather use laminar until Re<2000 and then switch to RANS, but the result is a sudden drop in the curve. Can I actually use RANS from the very beginning (Re<200) ?

    Shiuh-Hwa Shyu

    For laminar flow, you probably can just used one set of mesh. Of course, mesh dependency has to be checked for that mesh. In transition and turbulent, your mesh distribution will depend on the Reynolds number. That's one reason that turbulent flow is so difficult to solve.

  • Murat Ozdemir added an answer in Abaqus:
    Is the mesh size affect the beam stiffness in finite element analysis ?

    when i decreased the mesh size in modeling of RC beam in abaqus the beam became stiffer in the elastic zone i don`t know why ??

    Murat Ozdemir

    Firstly,  I am not familiar with ABAQUS. As for your problem please see below;

    Ultimate capacity may not reach the experimental load carrying capacity because of several reasons. For instance, it is quite difficult to satisfy exactly same BCs for FE simulations and expeirments. Another possible reason is initial imperfections, such as initial deflections, welding residual stress etc. If you can model both BCs and initial conditions exactly same as experiment conditions, you could obtain similar results with experiments. 


  • Andrey S Bavykin added an answer in Agarose Gel:
    Why is my RNA not showing up on a 1% agarose integrity gel?

    I have attempted Trizol RNA extraction from polysome fractions using HCT-116 cells. The 260/280 ratios for all of my samples are between 1.6 and 1.8 (when I quantified RNA on the nano drop) and the RNA concentration ranges between .74 ng/uL to 137 ng/uL in my samples.

    I made a 1% agarose gel and ran my samples (first 200 ng) on this gel at 100V for 40 minutes with 3 uL of EtBr (added to the gel itself). Only the ladder showed up when I imaged.

    Next I tried loading more about 800 ng of RNA total concentration with 6X loading dye and DEPC water and again only my ladder is showing up.

    I would like to do PCR with these samples but I want to see the integrity of my RNA. Anyone have experience with this? Or suggestions would be greatly appreciated!

    Andrey S Bavykin

    You have low RNA ratio. It should be 2.0-2.2, especially from the cell line. You do not see RNA, because you do not have it. Repeat the extraction.

  • Amit Pawar added an answer in FLUENT:
    How to set the Velocity Magnitude and Direction in FLUENT?

    Hi again,
    I am trying to understand how the setting of inlet in the FLUENT, specifically, the Velocity Magnitude and Direction. Someone could explain me, please?
    I'm working in 3D domain.

    Amit Pawar

    U component is cosine 24 and y component is sine24

  • Petr Mikheev added an answer in Graphite:
    What is the young's modulus and poisson ratio of Graphite like carbon (GLC) material?

    Please suggest some research article which provides young's modulus and poisson ratio of Graphite like carbon (GLC) materials

    Petr Mikheev

    On your question there is no general answer. Properties depend on a look and the scheme of reinforcing of material, the direction of loading and temperature. The module of elasticity of Carbon-Carbon materials strongly grows from room temperature to 1500 degrees Celsius.

  • Martin Henze added an answer in API:
    How can I convert "PCAP" format into "ARFF" format?

    (some datasets are just the observation of the network flow in terms of packet. I need to convert them to arff format to get the features)

  • Gurkirt Singh added an answer in Image Annotation:
    What is the suitable algorithm for multi-instance multi-label region annotation?

    I am working on region annotation. I have segmented the image into unique regions. I need the label the regions. I have also extracted features for these regions. How am I to annotate these regions . Can I do with ensemble classifier.

    Is there any algorithm exclusively for region annotation available or can I use existing image annotation algorithm?

    Gurkirt Singh

    you can try this


    free copy link is available on scholar.google.com

  • Rezvan Sharifi added an answer in Polyurethane:
    Who knows how can I stabilize the polyurethane foam?

    Why the polyurethane foam clings to the side?Also used stabilizing!

    Thanks a lot

    Rezvan Sharifi

    Thanks Dear Rafik 

    In fact, I'm using polydimethylsiloxane, but narrows foam and is not stable yet. I read some paper of Harith, I changed a catalyst, and I'm using DMEA and other amines. (Beafor i use Tin),  Foam isnt  stable  absolutely and  no resistance mecchanica. It breaks easily.


  • Mohammad Ahshanullah added an answer in Work-Life Balance:
    What is best method of longitudinal studies particularly will be relevant to work-life balance research?

    The term longitudinal study is very common in social science studies. Currently, I am working on work-life balance. Is there any relevant article related to longitudinal studies on work-life balance? What is best method of longitudinal studies particularly will be relevant to work-life balance research?

    Mohammad Ahshanullah

    Thank you all.

  • Madiha Khalid asked a question in Huh7:
    If somebody have done transwell migration assay using Huh7 cells can comment onto this?

    I am working on to the ATP induced migration of Huh7 cells via activation of P2Y receptors.

    1. I need to know whether it would be logical to use serum free media in both insert and the plate well. (0% FBS in both wells)

    2. If you would to see the effect of ATP would you be treating the cells with ATP or just adding the ATP into lower chamber media (Plate well).

  • Marcos Augusto Lima Nobre added an answer in Materials Physics:
    What is the procedure for make pellets for ferroelectric studies and silver paste coating on pellets surfaces?

    What is the procedure for make pellets for ferroelectric studies and silver paste coating on pellets surfaces?

    Marcos Augusto Lima Nobre

    Dear Dr. Subramaniyan:

    Electrical Measurements in Electroceramics/Ferroelectrics

    Sample Preparation:

    Superficies to receive electrode: perfectly parallel and high polishing degree, commonly reported as mirror like degree, from adjust of sample angle it is possible observe the eyes yourself.

    Electrode preparation:

    Ag Electrode: Ag 98% pure to 99.9% pure.

    Electrode position: geometric center of sample, at simple configuration. Lines of electric field belong to the electrode border interact with sample.

    Electrode aligning: both electrodes should be perfectly aligned.

    Deposition: can be direct painting on the position. Some training is necessary despite of necessity of use a mask to protect almost sample surface; only area associated to electrode should be free.

    Electrode fixation, first step: typically the Ag is disperse in a volatile solvent, then after painting gradual solvent elimination should be provided, at room temperature 24 hours can be sufficient.

    Electrode fixation, second step: typically the Ag deposit is cured via thermal treatment. Under a slow hearting rate, in air atmosphere, temperature should be increased up to 200 oC – 250 0C, soaking time 2 – 4 h. Here, know-how is important since some parameters depending on the Ag particle size and its concentration. It is important, electrode characteristic via Scanning Electron Microscopy verifying, at least one time.

    Electrodes in action: unfortunately, despite of low cost, Ag exhibits some temperature limitation of application. This event is not correlated with the fusion temperature 961 – 962 oC. In fact, the existence of a limit of application is assigned to other phenomena that are the good chemical interaction with inorganic materials and oxidation. In this sense, temperature of measurement can be limited to 350 oC to 400 oC.

    Best regards

    Marcos Nobre

  • Thies H. Büscher added an answer in Aquatic Insects:
    How trustable is to work using the taxonomic keys on Heckman aquatic insect encyclopedias?Exist an error compendium or similar to work with?

    Use of the Encyclopedias of Aquatic Insects of South America

    Thies H. Büscher


    what's your intention for using it? I guess it is quite fine for families e.g. For the further identification I would use subsequent keys fot the distinct taxa. The insect diversity of South America is not that well explored, that any comprehensive book could be reliable for identifying insects to species niveau. 

  • Suhas Dinesh added an answer in Waveguides:
    What is the Maximum Skin Depth used in Waveguides?

    I was recently told that the maximum skin depth (δ) used in waveguides is 6δ. Usually it is kept to a maximum of 5δ, as the waves cannot penetrate beyond this at high frequencies. Why is it 6δ and what is the reason for it?

    Suhas Dinesh

    Can you please give me an example where the Skin Depth calculates to 5.3.

    Thanks for your help, Dhanu Chettri!

  • Gunakkunru Anbullan asked a question in Dosage Forms:
    Do anyone have topical dosage forms classification in terms of viscosity?

    Do anyone have topical dosage forms classification in terms of viscosity? For example, less than 1000 cps may be liquid dosage forms such as lotion and topical solution

  • Gurkirt Singh added an answer in Images:
    Do you know any hard cell segmentation problem, with noisy data on a noisy background?

    I am working on a new image filter and I would like to test it on some biological images.

    Gurkirt Singh

    For one you can try 


    or search other dataset in 


    These dataset are very standard and comes with ground truth and baseline.

  • Lauriane Janssen asked a question in HPLC Analysis:
    DMSO or GuHCl 6M to wash out proteins stuck on a RPC-C4 column?


    I would have a question regarding RPC column care.

    I seem to have proteins that are stuck on my RPC-C4 type column, and I was wondering if you have any input concerning the best way to wash those out.
    I previously tested GuHCl 6M and DMSO on another column, and both seemed to work, but as the column did not react "normally" after those washes (even after extensive water and ACN washes and equilibration), I wonder if this is safe for my column.

    Thanks for your input.


  • Christian Baumgarten added an answer in Decoherence:
    Is there a Wave Function of the Universe?

    Different physicists disagree on whether there is such a thing as the wave function of the universe.

    - In favor of its existence is the fact that, in the Big Bang picture, all particles (and hence downstream objects) were correlated at the inception of the Universe, and a correlation that has existed at some point in the past ever so loosely continues thereafter since full decoherence never truly sets in. A number of pictures  - Ghirardi-Rimini-Weber, Bohm, even Hugh Everett, et al., - demand that  the existence of the wave function of the universe, denoted Ψ(U).

    - Two main categories of objection however belie its existence.

    The first category ultimately boils down to a not very solid rejection of non-separability, i.e. to an argument that a full separation between an observer and an observed must always be upheld if any observation or measure is to be objectively valid, and a wave function ascertainable.

    The second argument is more compelling, and says that if Ψ exists, then Ψ(U)=Ψ(Ψ,U) in a closed, self-referential loop. Ψ has thereby become an non-observable, unknowable, and as such better relegated to the realm of metaphysics than physics.

    What say you?

  • Gurkirt Singh added an answer in OpenCV:
    Is it possible to write SIFT (Scale Invariant Feature Transform) detector and descriptor program using c++ language only?

    I am working in Image Processing research field. I want to make a c++ program for SIFT and I don't want to use OpenCV library for it.

    Gurkirt Singh

    If you wish you can write yourself or use the cpp implementation provides by Vedaldi


    This implementation is open source and very close to SIFT implementation of David lowe. They show the comparison on the page as well. 

    OpenCV is good open too.

  • Richard Chapman added an answer in English Language:
    Can ELF be the language of the "3rd culture"?

    English as a lingua franca

    Richard Chapman


     thanks for starting up a really interesting discussion.

    Your question at the end is something that is at the heart of the ELF debate, in my opinion. You're quite right to use quotes when you do, but I would also be tempted to put them around the word 'learn' as well. The idea of "native English speakers" participating genuinely and respectfully in ELF cultural exchanges is fundamental, but it might also be a big ask. Learning ELF for a NS of English will be a very different experience from my struggles with French and German at school (without the feelings of bewilderment, overload and relinquishing control etc.), but this need not mean it will be a lesser experience for that. There is a lot of work to be done on the idea of NS English speakers becoming 'semi-bilingual' with ELF as their second bowstring, both theoretically and with practical observation. 

  • John J. Hains added an answer in Water Quality Assessment:
    What are contour maps? how they were drawn? how they are helpful in water quality assessment?

    i wish to know about contour maps and their significance in water quality assessment kindly help

    John J. Hains

    There is a short PowerPoint presentation that was produced by Minnesota that covers how to do this. The presentation is a 'primer' on morphometry and does a nice job of summarizing the various methods of creating a contour map of a lake basin::

    I'm not sure this link works but you can search for the presentation by searching for: Minnesota water on the web Morphometry

    The presentation should occur near the top of the search list.

    In slide 39 there is an algebra error but the resulting equation is still correct.

    Good Luck

  • Vladimir A. Kulchitsky added an answer in Climate Change:
    Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?

    Isn't the obvious solution and the elephant-in-the-room 'BETTER HUMAN BEINGS'? Shouldn't the focus be on better human beings rather than better technology? Why is it that everyone wants to develop better technology rather than focus on better humanity? Because no one has the answers and no one wants to change themselves? In environmental degradation, is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?

    " Our studies must begin with our selves and not with the heavens. "-Ouspensky

    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.

    We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    The Mind is the Final frontier.

    + 2 more attachments

    Vladimir A. Kulchitsky

    Dear Raveendra! Dear all! Please, attention! Can Specialist to objectively evaluate the work he has done? I believe that - not. There will always be an element of subjectivity. What mother says that her child bad compared with others. Mother always find the positive traits in your own child. And it is right. From this perspective, all the international jury, which evaluated the creativity of citizens of different countries, always bring an element of subjectivity in the vote, and often policy. And we see how it actually manifests itself in critical assessments. Thank the Creator, that for example, in sports, in competition, e.g., in the sprint there are conditions that help to win really Quickly. And we see objectively violated subjective conclusions about the traditions of victories only certain representatives of the nations.
    Thus, when the focus on the human dimension it is advisable to think about an Objective Judgment. And this Judgment takes place, but in Another Dimension.

  • Rida Azmi asked a question in RapidMiner:
    Image processing with RapidMiner


    i need some tutorials about image processing tools in RapidMiner 


  • Ravindra Ramachandra Mudholkar added an answer in Collecting Data:
    How can we fuzzify data collected (on the scale of 1-10) from 50 people?

    How can we fuzzify data collected (on the scale of 1-10) from 50 people.I have not considered any linguistic scale rather i have collected the data from 50 well known people from industry?

    Does averaging of the data & fuzzification/defuzzification process gives same result?

  • Panchatcharam Mariappan added an answer in Language Modeling:
    I need help in C language modeling specially related to solving Production/supply chain problems?

    I need help in C language modeling specially related to solving Production/supply chain problems.

    I will thankful to anyone who can provide any book/material for coding solution algorithms.
    Need some basic material.


    Panchatcharam Mariappan

    There are many commercial software available in the market. For example, SAP


    This book explains the algorithm


    There are open source software available such as openboxes


    apache ofbiz


  • Suhas Dinesh added an answer in Waveguides:
    Why TE10 is the only mode considered in waveguides and microstrip structures?

    Why is it that TE10 is the only mode considered while observing output in case of waveguides or microstrip structures? Why not TE20 or TM21 et al.? Is it because the higher order modes have higher cut off frequencies? Or is it because more probes/SMA connectors are required to excite/observe the characteristics? 

    Suhas Dinesh

    I understand that TE10 is the dominant mode ... et al. My question is why is TE20 mode or TE11 and other modes not considered while studying/simulating/measuring a waveguide or microstrip line? Why only TE10 mode?

    "... at the frequency-band of operation only the dominant mode is propagating, while all higher-order modes are cutoff."

    Let the waveguide operate in the X-band (WR90). Here TE10, TE01, TE11 and TM11 modes can propagate (TE10 and TE01 have different cut off frequencies). It is not just the dominant mode that is propagating in the waveguide!

  • Tichaona Sagonda asked a question in Tobacco:
    How do I extract pure colonies of Sclerotinia sclerotiorum from fresh tobacco leaves for the purposes of DNA extraction

    I have just received fresh samples of tobacco leaves with white mold on them. So I am trying to ascertain the genetic diversity of these "fungi"