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  • Jason White added an answer in Protein Labeling:
    What are the protocols for protein labeling by using antibodies?

    Hi all,

    I've harvested recombinant protein with 6xHis tag (~0.3mg/ml). And I wanna check it under confocal microscopy for in vitro exp. So I plan to conjugate protein with fluorescent reagent by using anti-6xHis antibody. But, I can't find any protocol for the protein labeling through antibody, anyone can help? Thanks

    Jason White

    As Jaime mentioned, there are numerous kits available for protein labeling with fluorophores. Check ThermoFisher or Life Technologies. Depending on the PI of your protein, you should be able to find a suitable functional group (i.e. succinimydyl ester, maleimide, NCS, etc). Most kits will also come with the gel columns that Jaime mentioned as well. If not, spin columns (BioRad) or PD-10 columns (GE) work well. 

  • A. Subba Rao added an answer in Crop Production:
    What is the potential of the North East Soils of India?

    NEH soils are though acidic in nature, but due to high rainfall, suitable climatic conditions and high organic matter content many valuable crops can be grown in this region.

    A. Subba Rao

    Can any body working in the North East supplement on the extent of diversified farming being practiced ?Diversified farming may provide more livihood and food security as the farmers can get employment and income throughout the year.Of course rainwater harvesting is an important component to support multienterprizes.

  • Ilya Tsyrlov added an answer in Nuclear Proteins:
    What percentage of nuclear proteins represent transcription factors?

    I tried to find that info but I still can not solve that problem.  What percentage of nuclear proteins represent transcription factors?

    Ilya Tsyrlov

    Hi Andrzei,

    Without giving you a precise percentage of nuclear proteins representing transcriptional factors (not sure anybody would), it seems this percentage value is substantial, and – this is the key circumstance - further growing. The latter is due to continuing revelation of new cascades of transcription factors. We now know that the tissue-specific expression of a particular gene, let say, such as the gene encoding the δ1 crystallin of the lens, is the result of the presence of a particular constellation of transcription factors in the nucleus. In the case of this lens crystalline, the Pax6 and Sox2 transcription factors are especially important. It is important to see that this combinatorial mode of operation means that none of these transcription factors has to be cell type-specific. But how do the transcription factors themselves get to be expressed in a tissue-specific manner? In many cases, the genes for transcription factors are activated by other transcription factors. Let us look again at the Pax6 gene as an example. Not only does the Pax6 protein regulate other genes (such as the ones for insulin and crystallins); it is itself regulated. The regulatory regions of the mouse Pax6 gene were discovered by taking regions from its 5´ flanking sequence and introns and fusing them to a β-galactosidase reporter gene. This transgene was then microinjected into newly fertilized mouse pronuclei, and the resulting embryos were stained for β-galactosidase. An enhancer farthest upstream from the promoter contains the regions necessary for Pax6 expression in the pancreas, while a second enhancer activates Pax6 expression in surface ectoderm (lens, cornea, and conjunctiva). A third enhancer resides in the leader sequence, and it contained the sequences that direct Pax6 expression in the neural tube. A fourth enhancer sequence, located in an intron shortly after the translation initiation sequence, determines the expression of Pax6 in the retina. The search is on now for those transcription factors that activate the gene for the Pax6 transcription factor. It might sound funny, but Wilhelm Roux in 1894 described this situation eloquently in his manifesto for experimental embryology when he stated that the causal analysis of development may be the greatest problem the human intellect has attempted to solve, “since every new cause ascertained only gives rise to fresh questions concerning the cause of this cause.”

    Best wishes,


  • M. M. G. T. De Silva added an answer in Water Cycle:
    Can you please suggest me about good software to model water cycle?

    It is good if the software is freely available and user friendly. It is OK evenn if it is an open source software

    M. M. G. T. De Silva

    Dear Professor,

    Thank you very much for your valuable information. 

  • Samy El-Tawab added an answer in VANET:
    Can anyone help me with the latest research/white papers on Latency and QOS issues in VANETs?

    Specific research on MAC layer protocols or any such criteria

    Samy El-Tawab

    Check attached paper and its references.

  • Xinhua Wang added an answer in Sliding Mode Control:
    Anybody worked in Sliding Mode controller for SIMO system?

    Is it possible to use Sliding Mode controller for Single input multiple output system?

    Xinhua Wang
    Maybe sliding mode controller based on the generalised inverse is available.
  • Khaled F M Salem added an answer in Plant Biotechnology:
    Which SRAP, ISSR, AFLP and SSR markers will be more robust and applicable for hybrid purity check?
    I want to use SSR markers, I think these will be good for hybrid purity checks in vegetables (Cucumber, Brinjal, Chili and Tomato) and I am also looking for the sources for SSR markers in Cucumber if anybody has Idea let me know.
    Khaled F M Salem

    Dear Dr. Anand A Khot ,

    Greetings, thank you for your question.

    SSR is the best DNA markers because it is specific for genome, co-dominant, and other advantage for each crop you could get specific SSR. You will get a specific band for each genotype and you could show the differences between genotypes and you could check the purity for your materials.

    with best regards


  • Marc Baqué asked a question in International Environmental Law:
    Does anyone know literature that covers the impact of formative events (i.e. Chernobyl, Fukushima) on the legalization of environmental/nuclear law?

    I want to know if there is or has been a legalization effect on the International Environmental Law or Nuclear Law by the International Atomic Energy Agency because of the 2011 Fukushima reactor accident.

    But also the effects on legalization by the Chernobyl accident would be really helpful to have something to compare Fukushima too.

    Thank you very much!

  • Dorothy Chipo Madamba asked a question in Calliphoridae:
    Anyone working on African Diptera: Calliphoridae taxonomy?

    I am looking forward to exchanging ideas with researchers working on Diptera: Calliphoridae taxonomy especially African species.

  • Diana Kwok added an answer in Multilevel Modeling:
    What software would you recommend for multilevel modelling?
    I would be very grateful if you might present limitations and unique advantages of multilevel modelling software based on your experience. Thank you!
    Diana Kwok


    This is a very insightful discussion and I am so pleased to have found it.

    I am a PhD student working on a policy capturing study and still figuring out what my data analysis needs are. I am thinking of purchasing HLM7 but the user manual was not written for novices like me. Oh yes, I have limited statistical and programming knowledge.

    Thanks to Kelvyn I have found the extremely helpful resources on CMM's site and signed up for a LEMMA course.

    Going back to Luis' comment on "What's the best car out there?", I would start with Hierarchical - multivariate analysis and Non-linear - cross-classified analysis.

    Which software would you recommend given the above 'constraints'?

    Thank you.

  • Carlos Araújo Queiroz added an answer in Graphene Oxide:
    What is the best chemical method for synthesis of graphene oxide from graphite?

    I am reasonably new to this area of reasearch. I have searched literature and found different chemical methods for synthesis of graphene oxide from graphite. The most common method was Hummers modified and improved method. I decided to use modified hummers method but different literature mentioned different experimental conditions (particulary the temperature used in the synthesis) though the chemicals employed remained same for most procedures. 

    Can somone provide an optimal procedure with reliable literature for the synthesis of graphene oxide from graphite using modified Hummers method? 

    Carlos Araújo Queiroz

    There have been a few related discussions at this forum:





  • 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 in a previous response. 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.