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  • Mostak Ahmed added an answer in Cell Culture Techniques:
    How do I culture cells with drugs?


    I am planning to design a protocol for culturing the following 2 cell lines with the drug (Gefitinib: 4765 (cell signaling technology). Could you please help me find any specific and detailed protocol how to do it?

    CRL-5908 (NCI-H1975)
    CRL-2868 (HCC827)

    Mostak Ahmed

    Hi Caner

    Many Thanks :)

    My intention is to purify protein through IP from cell cell lysates already pretreated with drug. And then detecting post-transnational modifications.

  • Florencia Maldia added an answer in Classroom Research:
    Apart from questionnaires, are there other reliable ways of assessing school climate?

    Apart from answering this question, can you please recommend useful sources on school climate?

    Florencia Maldia

    Interview and in-depth analysis of review of related literature on school climate will provide you additional data in the study of school climate. In this case your method is mixed method  using different sources of data collected, analyzed,  integrating the  findings, and drawing inferences by using both qualitative and quantitative  methods in a single study. Best wishes

  • David T. Risser added an answer in Ethical Analysis:
    Which influential ethical theorists claim that inter-subjective attunement (sharing affective states with others) is necessary for morality/ethics?

    I'm looking for influential thinkers who argue that intersubjectivity is necessary for being moral and/or living a good life. Ideally I want to find examples of well-known analytic, continental, and feminist thinkers who hold this view. Thanks so much!

    David T. Risser

    Dear Anabel,

    You are clearly well acquainted with Hume's ethics.  But, it is difficult for me to conceive of the impartial point of view as a natural capacity, although it makes sense to me that from that point of view, we judge all humans to be equally valuable.  You speak of "all beings as equally valuable", from the impartial point of view.  I also noted your commitment to the moral "considerability" of a broad moral community which includes non-humans.  Do you find Hume's ethics to be compatible with Buddhism, which I noted is one of your areas of interest?   Also, the ability to judge, from any point of view, strikes me as requiring language and society.  If so, in what sense can the capacity to judge be natural?  Or, in what sense do you mean "natural"?  Perhaps, I should do some re-reading of Hume before you take time to answer my admittedly unclear questions.


  • Anne Power added an answer in Women:
    Has anyone conducted research into women composers?

    We are about to launch a project into the careers of women composers. Does anyone have data on this? We would love to hear from you!

    Anne Power

    Sally Macarthur is someone you might speak to, at this University. She has several books and journal articles: Feminist aesthetics in music; Towards a 21st century politics of music; Feminist aesthetics in music - politics and practices in Australia; The woman composer, new music and neoliberalism. She also has conducted study on Ann Boyd's music. If you want me to say anything to her, I'd be pleased.

  • Ramesh Prasad Bhatt added an answer in Water Quality Analysis:
    What are the research parameters of river water quality analysis?

    Generally we use WQA for drinking water using WHO standard or national water quality indexes. Some countries also following river water quality analysis as per plankton, algae, benthos and invertebrates (aquatic flora and fauna. Fish species and their feeding ground would be the another parameter we can assume for WQA. Besides these what are the scientific standard as we can use the best method for river water quality analysis?

    Ramesh Prasad Bhatt

    Dear Ahmed Sir, Its ok but what are the ranges for toxicity or acceptable level for feeding backgrounds eg, animals, fishes, microbes, plankton, benthos, algae etc.

  • Lloyd Ling added an answer in Garbage:
    How can we calculate cost of valueless materials which can be converted into a value next times?

    This question is related to garbage valorisation. In producing time, materials can be eroded, every three situations (solid, liquid, gas phases). eroded materials don't be considered in any cost statements. But, this situations, direct or indirect, reveal two tips of costs: waste disposal or recycling both internal and external. we focus on internal recycling which is physicallly appears but no value materials.      

    Lloyd Ling

    Perhaps you should also include "Upcycling" concept to quantify sustainability and future value generation. The value of the end product(s) from recycling and upcycling effort allows you to justify your present cost. NPV analysis is a good start BUT you have to spend some time to identify your discount rate in your calculation.  

  • Andre Lengert added an answer in Next Generation Sequencing:
    Can anyone suggest me some Next Generation Sequencing manual or guide book..??

    can anyone suggest me some Next Generation Sequencing (NGS) manual or guide book..??

    Andre Lengert

    I dont know what your goals are, but here are some options: 



  • Dismas Choge added an answer in Quantum Optics:
    How can I increase the frequency of photon pair generation via spontaneous parametric down conversion (SPDC) to an ultra-fast magnitude?

    Solid-state lasers used to pump SPDC crystals can produce light pulses at rates only up to a few hundreds of MHz. Can someone suggest to me a scheme of say doubling the rate of photon generation using the same laser pumps. I will also appreciate any link to publications that can give me a better insight.

    Dismas Choge

    Hallo Gintarus,

    A bundle of thanks respected sir. I have learnt quite a number of things that I didn't know initially. It has really changed the way I should approach my design.

    Thank you

  • Santosh J. Dubey added an answer in End User:
    Is it plausible to capture the knowledge of domains in a set of archetypes?

    We need thorough knowledge of domains to create applications, products, services and platforms to serve customers and end users. Domains are vast reservoir of knowledge. Mastering this knowledge is no easy task. Given that there are multitudes of domains this task becomes humongous. This task can be made easier if we unearth a set of archetypes that can capture major portion (100% does not seem plausible) of knowledge across domains. We, of course, need to contextualize these archetypes. 

    Santosh J. Dubey

    Hi Juan, Noted with thanks.

    Hi Steve, noted, but the quantification of factors poses the issue of individual impact, right? I mean if decision-making is to be quantified, then we have the issue of the impact each of these factors on the model's product. How do you demonstrate this idea, which makes sense in the qualitative area though.

    I think the latter factor (what you call a black box) can be percentile based significance, probably a constant that can be defined, it is understandable. But then, that's my issue with archtypes, you know, the need for static variables... when the strength of each attribute can differ across subjects. Even if we do allow for dynamic attributes, we will still be left with ambiguities... which ultimately require some form of discretion. Defeats, the purpose, right? How do you get around that?

  • Kerre Willsher added an answer in Collective Learning:
    What collective learning processes would predict team performance ?

    I am doing a litterature review on collective learning processes that would predict different kind of performance in a team. I want to check that I'm not missing something I wouldn't have thought of by asking you this question !

    Kerre Willsher

    Hello Raphael,

    You might like to consider if the collective had set agreed upon goals and had any concerns.  Organizations that have diversity often work better than those that have monocultures.   However,  extensive preparation and consultation with key stakeholders is required.  Kerre

  • Aaron M. Barlow added an answer in X-Ray:
    What is the different between laser and x-ray?

    what is the different between laser and x-ray?

    Aaron M. Barlow

    Light is electromagnetic radiation. It is a wave with a wavelength, a frequency, and a speed. The wavelength/frequency of the light determines its "colour": Light that has a 530 nm wavelength is green, 600 nm is red, 450 nm is blue. The 200-400nm is ultraviolet, which we can't see, but is responsible for sunburns and things. The infrared runs from 800 nm to 3500 nm or so, which is commonly thought of as heat energy. Other wavelengths include microwaves, radio waves, and X-rays. X-rays are shorter wavelength than ultraviolet (0.01 nm to 10 nm as noted above).

    Light can be generated through many different methods. One simple way to generate light is to heat something up. When you turn on a light bulb, what you're doing is passing electricity through a metal filament, increasing its temperature to a few thousand degrees. This causes it to produce light. This light has a broad distribution of colours called a blackbody spectrum, that extends from the infrared all the way into ultraviolet and beyond, even producing a tiny amount of x-rays. Sunlight has a similar sort of distribution, and as quite accurately described by a blackbody spectrum with a temperature of 5800K. Laser light is different from blackbody light in that it is produced only at a very specific wavelength. If you shine blackbody light through a prism, you get a rainbow; if you shine laser light through a prism, you get the same colour.

    So x-rays are light that is a wavelength particular band, namely the colours with wavelengths between 0.01 nm and 10 nm. Laser is a method of producing light at one particular wavelength, which might be visible light (a green laser pointer has a wavelength of 532 nm), or invisible light like x-rays.

  • Maria Arismendi Gonçalves added an answer in Golgi:
    Can anybody help with PBMC stimulation with anti CD3/anti CD28?

    I need to detect some T cell surface markers from stored PBMC's. I stimulated them with PMA which didnt work for few of my surface markers like LAG3. I have tried antiCD3/anti CD28 (soluble) for a 24 hr stimulation and detetcted surface antibodies well. But now I need to look at cytokines like TNF, IFN. Wondering if any of you know as

    1. How long should I stimulate PBMC's with anti CD3/CD28 to detect cytokines. 

    2. How long is it safe to keep cells with golgi stop/golgi plug and Brefeldin. 


    Maria Arismendi Gonçalves

    Dear Krupa,

    As Dewton said, PMA+Ionomycin alone works well for cytokine stimulation and we are using it for IFN-G intracell FACS detection, our kit already contains PMA+Iono and Brefeldin A (BD 550583) and it works fine with a 2ug/mL concentration for 6 hours.


  • Ramiro restrepo u added an answer in Rationality:
    How do the economists define self-interest and rationality?

    How do the economists define self-interest and rationality so as to make these concepts different from the animal instincts, beast behaviour, and barbarism? What is that which forms and what is that which does not form the self-interest? Moreover, are these the behavioural guides for all individuals? Are these the collective guides for policy making? 

    Given the propensity for free riding in each economic-beast, does not the collective policy results into a collective free riding of those who make policies over those who do not?

    Ramiro restrepo u

    Lucio, no estoy hablando del pasado, el pensamiento dominante sigue pensando en el equilibrio general competitivo y en la metodología de Milton Freedman. El desarrollo sostenible es completamente una alternativa.

  • William Matern asked a question in Molecular Biological Techniques:
    Is there a problem with the Green and Sambrook recipe for a 10M Ammonium Acetate solution?

    A copy of what is printed in the fourth edition of "Molecular Cloning" by Green and Sambrook can be found here: http://cshprotocols.cshlp.org/content/2006/1/pdb.rec8067.full?text_only=true.

    I tried this protocol and had trouble. First, I tried adding 77g NH4AcO to 70mL H20 and ended up with ~135mL of solution (so it was already over 100mL). Second, it took ~10minutes to stir in the last bit of salt...adding more seems like it might take awhile to get into solution, if it will even go. Has anybody successfully made a 10M ammonium acetate solution using this protocol?

  • Bushra Khattak added an answer in Taq Polymerase:
    Which vector is best for proof reading polymerase?

    Hi, i want to know can we avoid use of LA taq polymerase because of not proofreading capability for ligation? Can we use another vector which is use for proofreading taq polymerase? Please suggest me any good vector except pGEM T vector?

    Bushra Khattak

    Thanks alot @Alejandro Martin Sir

  • Kerre Willsher added an answer in Ethics:
    Could people comment on the moral imperatives in caring for involuntary psychiatric patients?

    I am working with South Australian law but am interested in international law.  Who are the carers?.  What support do they receive?   Have used deontological and utilitarian ethics, where does ethic of care come in?  How can the needs of the patient be balanced with the needs of carers, families and communities?  Stereotyping of the patients and their needs is a  problem. 

    Kerre Willsher

    Thanks for that Napoleon.  I believe that we should individualise the care.  Was wondering how other professionals do this as I  have come across stereotyping from other professionals.   Cheers. Kerre

  • Marcio Roberto Miranda Assis added an answer in Virtual Machine:
    Is there any model that represents private cloud within public cloud boundaries?


    I am looking for a model where private cloud or private virtual machine can be  represented within a public cloud boundaries.

    Thank you.

    Marcio Roberto Miranda Assis


    May cometcloud federation could help you. In this architecture is possible create private associaion inside a public enviromment.

    Look for this subject in ieee explorer.

  • Marilia Takada asked a question in MEK:
    Has anybody used trametinib (MEK inhibitor) to treat xenograft mice by intraperitoneal administration? Could you share dose/reference?

    Xenograft mice study using trametinib ip

  • Hayk L. Khachatryan added an answer in PLA:
    I need help for explaining this attached DSC test here that is supposed to belong to white PLA filament polymer?

    I am doing improvement strength research by 3D-printing  and using PLA filament, but before begin, I must test that commercial white PLA for identification matching. 

    Required points 

    Tg and Tm , could I indicate presence of crystallinity ? Percent of crystallinity ?

    Hayk L. Khachatryan

    Yes, I do agree with Dr.  Abbas Jassim Lafta, the XRD may help a lot.

    But as far you may not have the XRD equipment in your lab I do suggest to use the DSC again.

    This method is able to compute percentage of crystanillity.

    The method of calculation is enclosed in article which link I attached.


  • Rafik Karaman added an answer in Gaussian (Software):
    Can we combine two separate molecular groups in Gaussian software?

    Is it possible to combine two separate molecular groups created in Gaussian software into a single large molecule? If so how can we do it?

    Thanks in advance!

    Rafik Karaman

    Dear Devi,

    I agree with the answers of my previous two peers, however, I suggest to do the following:

    1-Build your two fragments in the same file using ArgusLab

    2-Minimize both of them (together) by UFF (installed within Arguslab)

    3-Write the input file and save it as ------.GJF

    4-Run a single point calculation by AM, PM3 or any other methods.

    5-View the output file using Molden and connect the two fragments by changing the distance between the atoms of interest.Then you can start optimization by AM1 and ending with DFT calculation with the appropriate basis set.

    ArgusLab and Molden prograns are free downloaded programs.

    Hoping this will be helpful,


  • Oliver Manuel added an answer in Scientific Method:
    Is the modern approach to cosmology fundamentally flawed?

    With the substantial amount of anomalies, paradoxes and unexplained phenomenon in mainstream cosmology, one must question whether the modern approach in this field is sufficient. In most fields of science, development proceeds according to the scientific method: A phenomenon is observed, a hypothesis is made, scientific test(s) are conducted and the simplest answer is sought after. However, this does not appear to be the path that modern cosmology is following (as demonstrated by the attached figure).

    Subjects such as naturalness and fine-tuning have been highly debated in the areas of quantum field theory and cosmology. The argument is that if a theory must be fine-tuned, then there should be an underlying physical reason for such values. However, the vast majority of fine-tuned theories lack explanation and only seem to exist for the purpose of reproducing reality in terms of ad-hoc mathematical formulations. Thus my question is really three parts.

    • Do you believe the modern approach to cosmology is fundamentally flawed?
    • Is a fine-tuned theory that is fundamentally wrong, but can still produce correct predictions useful?
    • Was Richard Feynman correct when he stated “Science is the belief in the ignorance of experts”?

    Examples in cosmology:

    • Redshift versus Luminosity Distance: Requires accelerated expansion via dark energy
    • The Faint Blue Galaxy Problem: Requires disappearing galaxies
    • Dark Matter Cusp Problem: Requires unnatural arrangements of dark matter in galaxies
    • Local Galaxy Counts: Requires a local "hole" that extends beyond 0.05z
    • Horizon Problem: Inflation theorized
    • Size of Distant Objects: Unexplained or significant evolution
    • Planck Sigma_8 Problem: Hypothetical sterile neutrinos proposed
    • Hemispherical Power Asymmetry: ?
    • Directional Dependence of Cosmological Constants: ?
    • The Dark Flow: Theorized interaction with another universe
    • CMB Cold Spots: Massive voids proposed
    Oliver Manuel

    George Dishman,  Please answer the two simple (YES/NO) questions:

    1. Does the equation of state (EOS) of dense matter consider NEUTRON REPULSION?  

    • YES
    • NO

    2. Does the equation of state (EOS) of dense matter fit the precise measurements of atomic masses shown below in the "Cradle of the Nuclides"? 

    • YES
    • NO


  • Thomas Nann added an answer in Nanorods:
    Is there any possiblity of quantum confinement in tio2 nanorods synthesized by hydrothermal method

    The band gap of the synthesized nanorods( 3.5 ev) are found to be greater than the bulk after dye sensitization. so is there any correlation between the increased band gap value and quantum confinement( decresing particle size)

    Thomas Nann

    There is a number of conflicting reports on the exciton Bohr radius of titania. However, it is certainly well below 3-5 nm, which means Roman is absolutely right and quantum confinement is highly unlikely in your case.

  • Rasit Ata added an answer in Wind Energy:
    Is it possible to work on wind turbine with BLDC motor? What are the limitations and disadvantages?
    Wind energy
    Rasit Ata

     Dear Renganathan,

    You might be interested in this paper:


  • Ramón Martín-Brufau added an answer in PsychoPy:
    Has anyone used Mitsar/WinEEG together with some opensource software for stimuli presentation (e.g. OpenSesame/PsychoPy) and could share some knowhow?

    I'm about to get down to some research and best I can do right now is Mitsar 201, WinEEG and some opensourse for stimuli presentation. So far I have worked only with Psytask, however, I need software that will allow for more complex experiments. If you could provide any kind of knowledge how to tackle Mitsar compatibility with other platform, I would really used it right now. I don't know exactly where to start with it and have no idea whether it's even possible. I could use Matlab as well, I'm a beginner here, though, so please make your answers not to advanced. If you could refer me to some (online) resources, that would help a lot too. 

    Ramón Martín-Brufau

    Any news about a compatible software? Psychopi would be great. It's easy, powerful ... and free.

  • Dr. Muhammad Zubair Asghar added an answer in Scientific Publication:
    How do you increase the visibility of published article?

    I'm curious to learn about any additional PR steps you can take to increase the visibility of your published articles. Here are some steps I try to take (in various combinations, depending on the nature of the article):

    • Cite the paper whenever appropriate
    • Post preprint/postprint on arXiv/similar repository
    • Bring a pile of reprints to the next conference
    • Write a press release together with the press office of my university
    • Send announcements out on an appropriate email list
    • Put a paper copy in any academic lunch room I happen to visit

    What am I missing? What are your tricks and secrets?



    Dr. Muhammad Zubair Asghar

    Nice sharing dear Bahram Kazemian

  • Xingang Guan asked a question in Protein Elution:
    How can I get the recombinant protein without urea and salt?

    I had produced and purified the recombinant protein by genetic engineering. However, the protein was eluted from resin with high salt and urea solution. When I use dialysis method to remove them, the proteins aggregated.  When using ultrafiltration, the protein did not accumulate in upper solution. I just want the protein in low salt solutin but with high concentration.

  • W. M. Bernstein added an answer in Impulse Control Disorders:
    Are there any case reports of Modafinil causing imp use control disorders?
    Any case reports of Modafinil causing impulse control issues like gambling
    W. M. Bernstein

    I've never encountered it. And I prescribe it a lot.

    w.m. bernstein

  • Bruce E Oddson added an answer in k-means:
    K-medians vs k-medians - k-medians to ordinal data- do you agree with me?

    I've ordinal data - in my opinion I should use k-medians in spite of k-means do you agree with me?

    Thanks in advance.


    Bruce E Oddson

    I am sorry but the question as posed is not clear.

  • Pedram Abdollahi added an answer in Etching:
    LePera etchant - Why does in our case Picric acid crystallize on mixing with Sodium metabisulfite?

    We are trying to etch DP600 using LePera etchant. As soon as we add Sodium metabisulfite to Picral, the picric acid crystallizes as powder at the bottom. Even after stirring for long it does not goes back into solution. We etched despite all this and then picric acid crystallized on specimen surface. Can someone tell what we could be doing wrong? Thanks…

    Pedram Abdollahi

    The etchant is a mixture of two pristine solutions . Volumes of 30 ml of reagent 1

    and 30ml of reagent 2 are poured into two different beakers. "Just before the etching

    is started, the solutions are mixed in a small crystallizing vessel"

    + 1 more attachment