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  • What are the best expression and purification tags and best ways to express large human proteins in E. coli in Mg amounts?

    I want to express human proteins of ~1000 residues in E. coli and purify them with a tag at the N- or C-terminus that I can remove for structural studies. The 1400 residue human nitric oxide synthase protein can be expressed in E. coli for example for making mg amounts of pure human NOS. What positive experiences have people had and what suggestions might guide us in these efforts? I do not see why NOS should be uniquely suitable for this as it has multiple co-factors and a complex fold. 

    Yordan Muhovski · Walloon Agricultural Research Centre CRA-W

    Hi, Halo-Tag expression purification system from Promega may help.

  • Does anyone have any experience or know of a publication endorsing natural desiccated thyroid for fibromyalgia treatment?

    There has been some success treating autoimmune thyroiditis with natural desiccated thyroid. Additionally, I have heard that other autoimmune disorders are related to the thyroid, like Fibromyalgia. Are their peer reviewed articles or does anyone have any experience with the use of natural desiccated thyroid?

    Sharon Primerano · University of Phoenix


     Can you give me the name of your colleague In Texas? I have been contacting different professionals in the state I live in and I am not getting any good results. I would really appreciate that.

    Thank you!

  • Dr.K.Mophin Kani asked a question in Streams:
    What are the various methods to assess macro and micro benthic organisms in stream or river?

    I wish to know the various methods involving in the enumeration of benthic organisms in aquatic water bodies;

  • Alex Malins added an answer in Lammps:
    Can LAMMPS show negative pressure for NVT system?

    I am getting negative pressure for NVT system in lammps. I am maintaining double the height of free space on water system.  When I add only "ke, kspace" keywords pressure is coming +ve, but with addition of 'pair' keyword pressure gives negative value. Can anyone please explain what are the terms to add in pressure calculation and the reason behind for pressure obtained being negative?

    Alex Malins · Japan Atomic Energy Agency

    By free space do you mean a vacuum? It sounds like the water is metastable and trying to phase separate into liquid-vapour coexistence.

  • Yordan Muhovski added an answer in cDNA Synthesis:
    RNA quality troubleshoot. What is the ~50nt peak next to the marker in my RNA sample?

    I have extracted RNA using trizol reagent and have seen this peak in almost all of my samples. It seems to interfere with cDNA synthesis and qPCR. The samples are from turkey liver tissues stored in RNA later. The tissue's were completely homogenised in trizol. The sharp 28s and 18s peaks in the attached picture indicate that RNA is not degraded, So could the peak be any other RNA (tRNA, miRNA) or sheared DNA? Thank you in advance.

    Yordan Muhovski · Walloon Agricultural Research Centre CRA-W

    I agree with Goritsa, could be tRNA regaarding the size. If you want to exclude that is sheared DNA , you can treat with DNAseI. And if you wish to avoid interference with cDNA synthesis make mRNA purification. Good luck!

  • Kishore Kumar Grandhi added an answer in IDL:
    How do I perform IMF analysis to find the harmonics using MATLAB or IDL?

    What is IMF or EMD?

    Where is it actually needed?

    Where can I stop IMFs?

    Kishore Kumar Grandhi · Kyoto University

    Download the function from the link


    Just follow the instructions. It is very easy. 

  • Miguel A Cordero added an answer in Honduras:
    Are there reports and evaluations available about the parenting program "Parents as Teachers" (of the Chile Crece Contigo strategy)?

    I am doing research on parenting programs which support parents to raise their child's early literacy exposure. Also included are Honduras ("Madres Guias") and Colombia ("Familias en Accion"), and please feel free to respond if you know good resources on those. The paper is a comparative case-study to analyze effective programs in this area in Latin America. Thank you.

    Miguel A Cordero · University of Bristol

    Hello Kara,

    As far as I know, "Parents as a Teachers” is an intervention implemented in United States of America. In Chile is ongoing implementing a local adaptation of the original Canadian parenting programme "Nobody's Perfect”. Please, check last two abstracts posted in my featured publications at RG. kind regards, Miguel

  • Yordan Muhovski added an answer in Primer:
    I am having difficulty in amplifying the 5' end of the cDNA. Is there any efficient way to do so?

    This segment of the 5' end to be amplified is around 450bp. I have already used two sets of primer but till now what i have visualized is the primer dimers at the end for both primers. I had also done the PCR at different temperature gradient for annealing, still no good signals.

    Yordan Muhovski · Walloon Agricultural Research Centre CRA-W

    Hi, I would suggest to use PCR amplification kit for GC rich samples. I don t know what you mean as 5' end may be 5'UTR or promoter region but if this is the case , that part is often rich of GC which is not easy to amplify. Good luck!

  • Yordan Muhovski added an answer in Gene:
    Can someone recommend a good resource of first strand cDNA for cloning gene by PCR?

    Dear all, I am going to clone a set of genes which express in many common tissues, eg. brain.  There are a number of companies who sell such cDNA mix. It will be helpful if you can share your expertise or good experience by using such first strand cDNA from a certain resource, to clone genes, especially genes longer than 8 kb.  Thank you.

    Yordan Muhovski · Walloon Agricultural Research Centre CRA-W

    Hi , I am using 1st strand cDNA synthesis kit from Thermo scientific: http://www.thermoscientificbio.com/reverse-transcription-rtpcr-rtqpcr/revertaid-first-strand-cdna-synthesis-kit/. The kit is working well, but honestly I never try to amplify a gene longer that 2.5kb.Good luck!

  • Can anybody answer a few questions on nonlinear optical process?

    Since I have a little understanding of nonlinear optical processes, then I want to develop some expertise about them. My knowledge about  nonlinear optical processes is mainly based on the book "Nonlinear optics" of the Boyd 2ed, and my questions are around this book:

    1)Which model of the nonlinear susceptibilities is more precise, one which derived from Maxwell equations or one which based on Quantum-Mechanical Theory?

    2) If we want to perform upconversion, for example with proustite crystal, I need to use d_eff, in the table 1.5.2 ("Nonlinear optics" of the Boyd 2ed) we have two parameters d_22 and d_15, how we obtain from them d_eff?

    3) If we enter in the non-linear crystal (with second order susceptibility (kay2)) with two waves, how we (from the physical point of view know ) know which nonlinear process will be dominant: sum frequency generation, difference frequency generation or second harmonic generation?

    Thank you in advance!

    Aleksandr Aleksandrovsky · Russian Academy of Sciences

    This is the link for new IR upconversion crystal ZGP - http://eksmaoptics.com/nonlinear-and-laser-crystals/nonlinear-crystals/infrared-nonlinear-aggas2-aggase2-gase-zngep2-crystals/

  • Hani Antoun added an answer in Phosphates:
    Is Trabulsiella odontotermitis a phosphate solubilizing bacterium?

    Is Trabulsiella odontotermitis a phosphate solubilizing bacterium?

  • Daniel Ahmed added an answer in Particle Tracking:
    Is there any plugin for particle tracking in image J?

    Image processing, Image J

    Daniel Ahmed · Pennsylvania State University

    Thanks a lot Adam.

  • Alain Lesaffre added an answer in Machine Learning:
    What is the best book to learn Machine Learning?

    What is the best book to learn Machine Learning?

    One good reference is 

    Machine Learning
    The Art and Science of Algorithms that Make Sense of Data 

    From Peter Flach  

    Gives the foundations of the main methods of Machine Learning. Do no expect code but pseudo code. 


  • Jianwei Liu added an answer in Organic Agriculture:
    Is there any solution to treat table olive wastewater, especially with a high level of salt and polyphenoles?

    In organic agriculture, black table olive debittering is known to use high level of salt to achieve this goal. But the wastewater produced needs be treated before its disposal in the nature. Is there any approved method to deal with this dark salty wastewater?

    Jianwei Liu · Tongji University

    In our lab, we use electrodialysis to achieve desalination. But before that, you need to remove organic matters in the waste water to reduce ion-exchange membrane fouling during the process of electrodialysis.

  • Is the abnormal movement (behavior) an endpoint for ecological risk assessment?

    I am exploring technology that can result in a low cost, onsite assessment of aquatic invertebrate behavior (movement) as an endpoint for ecological risk assessment.  If statistical analysis can confirm a difference between movements of individual aquatic invertebrates upstream, in, and below stream of point discharge, would this be of use for phase 1 or other studies of risk assessment?  Thanks, Lou

    it's a great pleasure to share something regarding this dear Louis;

    during avoidance study there are at some points the organisms tend to avoid the situations in which they suppose not to live; this is what exactly the organisms like micro or macro organisms in river do. most of the macro invertebrate organisms which have the ability to move will avoid the condition persists over a particular area whereas the non-motile organisms are the real indicators for a long term impacts; their presence and absence in an particular region gives exact level  of threat in that particular area. this will give us the reality of the ecosystem.

    further the studies on accumulation of materials in plants and organisms gives the result for major risk assessment part.

  • Is possible to "measure" social or institutional innovations, or technology transfer procesess developed for small agricultural growers?

    Measuring innovation is cristal clear when a patent, an utility model, a plant variety or a new trade mark is developed by researchers. However, when social or institutional innovations are developed, or technology transfer is done with peasants or small farmers, innovation is very difficult to measure.

    Régulo León-Arteta · Colegio de Postgraduados

    Disculpen que no lo haga en ingles, porque el mio es muy rudimentrio. Pero puedo afrimar que si es posible pero se requieren de periodos de tiempo mínimos de cuatro a seis años y estudios regionales previos, Un aspecto crucial a considerar es el denominado capital social y que cada comunidad gestionará sus cambios de forma partticular. Desgraciadamente nuestra clase gobernante tiene metas cortoplasistas y ve como una agresión as sus intereses la deseada autogestión. Como sucede a menudo con las instiutciones educativas, que proclaman el autodidactismo pero en reralidad practican las horas "pompa", como parte de las curriuclas escolares descontextulaizadas. Disculpen el posible exabrupto pero los que vivimos en fomra cotidfiana.la terca realidad, no podemos pintarla de rosa. Lo peor es que la crisis mundial, será mas grave en ibero américa. Además si el magro presupuesto agropecuairo nacional es botin político, como se observa en las noticias cotidianas, No las de telvisa y azteca, no se necesita ser pitonizo para preveer el resultado. Nada me sustaria mas que aceptar que estaba equivocado dentro algunos meses...   

  • Karim Musálem-Castillejos added an answer in Linux:
    Can someone advise on Ubuntu on MacBook Pro?
    Want to install Linux (in dual boot) on my MacBook Pro 5.3. What do you suggest: Ubuntu 13.10, Mint, Elemantary Os or CrunchBang ?
    Karim Musálem-Castillejos · Centro de Investigación del Chaco Americano, Paraguay

    Hello Mohamed, I am sorry to reply so late, didn't notice this update before. About your question, I chose to completely erase Mac OS from the computer, making a full install with Ubuntu Live CD. Thus, I don't have a dual boot but just a Mac that fully runs on Ubuntu, and until now it has worked perfectly. In my case my computer was useless with Mac OS, so I just started fresh. I'm still wondering why it works so good, despite being told that it was a hardware issue. Maybe Ubuntu just copes better with the problem instead of the frequent "panic attacks" of the Mac OS. BEst regards!

  • Would you like to collaborate for a publication on pragmatic development in a foreign learning context?

    We conducted research on the development of complaint strategies in L2 (English) by Indonesian EFL learners. To see their pragmatic development we conducted research for one year. At the beginning of the study we elicited data of complaint strategies by using oral DCT. After one year, we collected data for the second time from the same persons with the same instrument, and compared the results to the previous ones to see any pragmalinguistic development. We obtained very rich data of L2 complaints. At the moment we have written a manuscript that reviews the development of pragmalinguistics of complaint strategies. Now we would like to improve the manuscript before submitting it. If you have some experience on the topic, and we would like to collaborate as a co-author, please let us know. Thank you.

    kind regards,

    Lakshmi Kala Prakash · Mae Fah Luang University

    Hello Agus, thank you for the offer. Before I accept I'd like to know more about your expectations with respect to my involvement in your publication and or ongoing research. Please also include your proposed timeline for the completion of this project. My email is 5771006258@lamduan.mfu.as.th 


  • Is there research evidence to suggest that educators need to understand the features of technologies before they can use them to enhance learning?

    I'm currently writing a paper and want to present the argument that educators need to understand the types of technologies at their disposal and their various features before they can make discerning technology selection and deployment decisions. However I'm struggling to find evidence for this.

    Does anyone know of any research that substantiates this idea? My paper is on Web 2.0 technologies, but the evidence could stem from any domain.

    Looking forward to hearing from you!


    Alfredo D. Holguín Alfaro · Universidad Privada del Norte (Perú)

    The project mentioned by Karl seems fantastic, and is an attempt to incorporate large-scale technologies for learning achievement.

    I agree that one of the first tasks is to determine the needs of students, but also the needs of teachers. Also, be clear about the objectives of each course but in a clear context of institutional objectives and the education system itself.


    El proyecto mencionado por Karl me parece fantástico, y es un intento a gran escala de incorporar las tecnologías para el logro de aprendizajes.

    Concuerdo en que una de las primeras tareas es determinar las necesidades de los estudiantes, pero también las necesidades de los docentes. Además debe estar claro los objetivos de cada curso pero en un contexto claro de objetivos institucionales y del propio sistema educativo.

  • Ralph Bright added an answer in Knee Osteoarthritis:
    Can I use any established questionnaire for knee osteoarthritis with modification without any legal problem?

    Anybody please suggest can i use any established questionnaire like WOMAC with modification of time frame, addition or deletion of questions according to my population without any problem in publication and with authorities of that questionnaire? Actually it is changed but i am using few of question from there along with their scoring pattern. Will there any problem or anybody who has worked with knee osteoarthritis and developed his own questionnaire guide me?

    Ralph Bright · Macquarie Stem Cells

    KOOS will work well for you. My patients fill in the questions/answers for themselves so that I don't have to be involved unless they are having difficulty interpreting the question.

    Pain variation in OA is interesting and certainly very variable. If you can relate it to genetic variation that will be very interesting.

    The neuropathic component of OA pain responds very quickly. Pain from inside the joint responds next then surrounding muscle pain and tendon pain is the slowest to respond.

  • Ahmad Taher Azar added an answer in Rough Sets:
    Can anybody provide a good comparision between feature selection methods using rough sets theory?

    There are many types of rough sets theory such as fuzzy rough sets, crisp rough sets, tolerance rough sets and so on. If some body can make a comparison between the feature selection capabilities of these extensions?

  • Mariusz Buciakowski asked a question in LMI:
    What is the good method for design feedforward controller using LMI?

    I want to design a feedforward controller using LMI. Can you recommend me a good method to design this type of controller using for example Hinf approche or publication on this subject?


  • Can someone advise me for coding to genetic algorithm for prediction modeling?

    genetic algorithm for prediction modeling

  • Is there a self-efficacy survey for STEM teachers?

    We have designed a STEM course for student teachers at University of Calgary and I am interested in identifying potential effects on teachers' self-efficacy for incorporating an integrated approach to STEM at school level.

    Armando Paulino Preciado-Babb · The University of Calgary

    Thanks for the self-efficacy surveys for Math and Science Brady. I also found a survey for engineering K-12 teachers. I will try to use these and the literature on STEM education to create a survey for "integrated STEM education," as opposed to math, science, engineering and technology as isolated fields.

    This is the reference for the teaching survey for engineering K-12, in case someone is interested.

    Yoon Yoon, S., Evans, M. G., & Strobel, J. (2014). Validation of the Teaching Engineering Self-Efficacy Scale for K-12 Teachers: A Structural Equation Modeling Approach. Journal Of Engineering Education, 103(3), 463-485. doi:10.1002/jee.20049

  • Ahmad Taher Azar added an answer in Fuzzy:
    How to use Genetic Algorithms on a fuzzy logic controller for tuning of PID parameters of fuzzy PD or fuzzy PI controller ?

    hello every one

    Plz any one help me. I want to optimize fuzzy logic controller with Genetic algorithm . I am attaching my file. I have written all (code/simulation file) properly with help of ga function which are available in MATLAB. but its not working. if any one get the ans plz help me. 


  • Has anyone experiences doing studies with members of the tea party and the democrats, especially with hard liners?

    I would like to do a study with 200-300 members of the tea party (republicans) and the democrate party, each. The more extreme the better.

    It is a short online study (around 7 minutes). What are the chances in getting this amount of participants? And what is a good way in recruiting participants, e.g., writing different local groups of those parties an email?

    Tom Postmes · University of Groningen

    We sampled US citizens via Amazon Mechanical Turk for a longitudinal study of identity change and politicization around the last US presidential election. The paper is forthcoming in Personality and Social Psychology Bulletin. The sample served our purposes, but it might be hard to recruit enough tea party supporters in this way. You can also try online panels (e.g., Qualtrics provide one) where you can specify the population you want to sample. 

  • How can I calculate the wt % of nano fillers?

    I'm preparing a blend of two polymers, a salt and a nano sio2 filler. the composition of two polymers are 40/60(wt / wt %) how much salt and nano filler should be added to it?  explain  this ratio in terms of gms

    Vikas V Gite · North Maharashtra University

    If you are talking about addition of nano particles into polymer. It has one term i.e. phr- parts per hundred resin. In this case consider 100 gm of resin, 1 gm of filler, this formulation is known as 1 phr nano particles.

  • How can we integrate theory of planned behavior with Elaboration likelihood Model for advertising research?

    My research topic is "Attitude towards Controversial Advertising : Developing a new model by generational cohort "by adapting Dr Waller -A proposed Response Model for Controversial Advertising.The suggested underpinning theories will be Theory of planned behavior (TPB)and Elaboration Likelihood Model(ELM).I am looking at how to integrate TPB & ELM? Grateful for any comments and advice.Thank you very much.

    John Ch'ng

    Sharifah Nurafizah · Universiti Teknologi MARA

    What about integrating TRA and ELM?

  • How can land use planning be co-related with differential policy pricing on Diesel and Petrol?

    I am intesrested in knowing that if we have different prices of fuel for different income groups then how would this help in reducing the usage of fuel thereby cutting down on environmental pollution. Also, how would this change the landuse pattern within the urban area. Or, would there be no change in land use?

    Shyam Lakshmanan · Universiti Teknologi PETRONAS

    Malaysia has implemented different fuel prices for different sectors, and it has lead to the blackmarket sales of lower priced diesel to other sectors.  This was done with nano-tagging and investment in special equipment to identify the naon-tagging and after huge investments, the system eventually was dropped.

    Now they are planning a new multi tier fuel pricing based on individuals income.  Which means, each time I go to fill petrol or diesel, I need to show my identification card.  That is somehow linked to my income, and that determines the fuel price I will have to pay for my purchase of fuel.  It has not been implemented yet, but this is what the rumour mill is saying.  Of course, the very rich, will have drivers to fill the fuel into their vehicles.  And if the drivers identification card is used, the rich vehicle owner may still get discounted prices.  Unless the system links a car with the driver.... The system gets complicated as you can see.  But it will probably also result in black market sales of cheap diesel from one side to the other.

    You could probably study what Malaysia has done, and see the effects to see what will be the end result. 

    Land use will depend on incentives given by the government to investors.  If for instance, the area has some resource, and the nation wishes to exploit that, it could give tax holidays and other incentives to attract the investor to convert that raw material.

    In many cases, fuel cost may not be so significant a deterrent, unless you are in countries like China and India, where inland transportation costs are a significant element in total cost of the product.

    When you compete domestically on an industrial basis, whatever the fuel price may be, if all manufacturers enjoy the same fuel price, then there is no deterrent to investment.  Hence land will be used by such industries and preference will be close to urban areas in order to have access to employees and markets for their products.  Generally infrastructure is also better nearer to urban areas.

    Main users of fuel will be transportation followed by industries generally. 

  • George Stoica added an answer in Science Teaching:
    Are there any good conceptually based lesson plans for any curriculum in High School mathematics?
    Just looking for something good to be able to present to a high school class.
    George Stoica · University of New Brunswick

    Dear Sam,

    Did you try to present combinatorics results in relationship with (elementary) probability theory, like winning in various casino games, or winning in various sports, in general counting problems?