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  • Jerry Rhee added an answer in Grounded Theory:
    What is the best way to operationalize grounded theory?

    Since many conceptual thoughts are embedded in memos ( which -according to Charmaz- remain private and unshared), I wonder how to best operationalize the steps taken before the Integration of the abstract analyses in the grounded theory?

    I agree with David in that one should not get wrapped up in abduction as a mentalistic exercise.  However, I don't believe that is a good characterization of abduction, at least certainly not Peirce's intention, which probably contributed to his desire to separate his philosophy from others (pragmaticism). 

    In fact, the purpose of the phi spiral abduction paper is to demonstrate how to produce a point of view from which to integrate materials, cell, tissue, physics, psychology, philosophy, math, evolutionary, educational and social sciences by dealing with an actual, situated reality that displays an aesthetic form that can capture the public's imagination.  The work is grounded in Peirce, Dewey, Goethe, Simon, Kahneman, Bruner, Wilensky, Gentner, Waddington, Devreotes, Sadoc, Fratzl, Pinsky, Alberts, as well as other modern experimental scientists.  I realize this is a large claim but the argument is, if not phi spiral abduction, which? 


    You mentioned in a previous post about the goal of GT.  If you are aware of the goals of Continental and Analytic philosophies, the following is a conversation that attempts to illustrate how abduction can be used to bring the poles in relation to explain why they are so often ostensibly in conflict.  It's an exercise, a demonstration.




    "The undertaking which this volume inaugurates is to make a philosophy like that of Aristotle, that is to say, to outline a theory so comprehensive that, for a long time to come, the entire work of human reason, in philosophy of every school and kind, in mathematics, in psychology, in the physical sciences, in history, in sociology, and in whatever other department there may be, shall appear as the filling up of its details. The first step toward this is to find simple concepts applicable to every subject [for example: one, two, three; sign, object, interpretant; chance, law, habit-taking or continuity" ~Peirce

  • Lauren Stanwicks asked a question in Motion Detection:
    Is there a software that can be easily used for motion detection in sleeping animals?

    I want to take video of a rhesus monkey while it is asleep in order to gauge its movements at night. I am looking for a software I can run a sleep video through that will quantify its movements or at least make it easier for me to score an 8 hour video of its nighttime movement. 

  • Ijeoma Esiaba asked a question in Platelet Activation:
    What beads are essential for calibration and standardization in analysis of platelet activation markers by flow cytometry?

    I am analyzing platelet activation markers CD62P and PAC-1 in whole blood using flow cytometry. Presently I am using calibration beads for the fluorescence. But I see some papers reference the use of beads for instrument standardization. Are these beads essential? What things do I need to look out for to achieve quality, reproducible analysis?

  • Cédric Delattre added an answer in Sucralfate:
    I want to know assay method for sucralfate by hplc?

    i dont have reference for sucralfate so shall i go for straight line regression method

    Cédric Delattre · Université Blaise Pascal - Clermont-Ferrand II


    this publication could help you for your topic:




  • Lloyd Chauncey Brown added an answer in Aspen Plus:
    How can I overcome a simulation problem with Aspen Plus?

    I am simulating a CO2 capture unit with MEA amine. Everything in the simulation converged except the recycle stream that is coming from the stripper to the absorber. I tried different operation parameters to make the stream converged, but still the problem persists. So any hint in order to tackle this problem? 

    Lloyd Chauncey Brown · General Atomics

    I don't have those species in my database.  By similar species I mean species with very similar chemistry.  Your dealing with amino acids and this is not at all my area of expertise but I think that you should be able to use equilibrium constants from other amino acids that differ only in the hydrocarbon part far from the acid groups.  Maybe you can find a series of amino acids and plot K vs some parameter and see where your compound would fall.  The simplest thing might be to measure the pH to determine the acid constants.  OK, I just did a Google search and found this http://www.cem.msu.edu/~cem252/sp97/ch24/ch24aa.html which gives the pKa for both functional groups of your molecule.  Those should be the equilibrium constants that you are looking for.

  • When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Charles Francis · Jesus College, Cambridge

    Andrew, yes simultaneity must be defined physically, and there are an infinite number of ways to do it. Ultimately this is why we use general relativity, not just special relativity. Then we have general coordinate transformations, not just Lorentz transformations to show that the fundamental physics is the same in all reference frames. Nevertheless since the physics is the same in all coordinate systems, we are free to study special relativity in coordinates with a particular definition of simultaneity which puts the laws of physics into their simplest form. As Einstein said, in his introduction to the general theory

    Special principle of relativity: If a system of coordinates K is chosen so that, in relation to it, physical laws hold good in their simplest form, the same laws hold good in relation to any other system of coordinates K' moving in uniform translation relatively to K. —Albert Einstein: The foundation of the general theory of relativity

  • Lesley Ruth Hart added an answer in Osteology:
    Do you have a rotocol to make osteologic discs?

    Does anyone have a protocol to make osteologic discs? E.g. hydroxyapitate discs. BD bioscience no longer produce them and the one protocol I have takes 3 weeks.

    Lesley Ruth Hart · University of Bristol

    Thanks. Unfortunately BD have stopped making these osteological discs !

  • Mohamed Omar asked a question in Dental:
    How to perform a dental finite element analysis and how to model it ??

    I need someone to share his expertise with dental FEA.. any help is appreciated ..  

  • Ali Chaibakhsh added an answer in PLC Programming:
    How to use serial MPI cable for communication with the Siemens S7-300 series PLC?

    I want to establish communication between KEPServerEX and Siemens S7-313-c2-DP PLC using Siemens serial MPI cable (order no. : 6ES7 901-0BF00-0AA0). To do so, I was trying to download the PLC program through serial MPI cable. I have also tried different configurations of PG/PC interface for the serial MPI cable. However, I encountered errors in each case. So, what is the procedure to establish communication between serial MPI cable and Siemens S7-313-C2-DP PLC? Thank you.

    Ali Chaibakhsh · University of Guilan

    Dear Ankur,

    1- PG/PC interfaces are not working on Windows Vista, 7 and 8 (definitely not on 64-bit OS). Try to install Windows XP on your system or install a VMware Workstation and then install XP windows.

    2- install the Siemens PG/PC interface drivers and STEP-7 on the XP platform

    3- go to " control panel > setting the PG/PC interface" 

    4- select PC Adaptor (MPI)

    5- check the wire's connection to PLC (** port 1 or 2 **) , network address and baud rate

    6- restart your PLC

    7- on PCL explorer check the communication,

    see the attachment.

    good luck

  • What are reliable questionnaire or tests for PTSD diagnostic?

    Has someone recommendations for a particular test?

    Thanks so much

    Michelle Genis · Kent and Medway NHS and Social Care Partnership Trust

    Structured clinical / diagnostic interviews would definitely be the gold standard. If you're after a client-rated (self report) measure, it might be worth considering the Impact of Events Scale (Revised). I've found this helpful in exploring pre- post- treatment gains. 

  • Morteza Dalvandi added an answer in Metamaterials:
    Is there any material that can produce heat or electricity or any force with decreasing in temperature?

    I would like to know if any material with this situation does exist. And as I know there's just one material which decreasing in temperature can raise it's entropy, and it's dark material.

    Morteza Dalvandi · Khaje Nasir Toosi University of Technology

    I have to thank all of you guys for your helpful answers.

  • Meixia Shi asked a question in Cellulose:
    What's the main differences between two membrane materials "cellulose" and "cellulose acetate"?

    I saw people use "cellulose" or "cellulose acetate" to fabricate membranes. Obviously, the polymers' chemical structures are different since they are two different polymers. My question is: what's the main differences between these two kinds of membranes based on these two polymers respectively? Thanks a lot!

  • Dan Piraner asked a question in BSL2:
    Could someone point me to a reliable multi-round FACS protocol for mammalian cells?

    I'd like to use FACS to screen a gene expression system both pre- and post-induction. Ideally I would like to screen uninduced cells and keep the population with low fluorescence, introduce that population to the stimulus, and then re-sort for high fluorescence.

    I'm told that mammalian cells typically don't survive sorting well due to shear stress (suspension cultures are said to work well but I don't have access to a BSL2 shaker). Has sorting and re-sorting of adherent cells been done (I don't have a cell type preference)? My theoretical library size is on the order of 1000 variants so I think I could tolerate a fair amount of loss. If this is not possible, what's the best way to recover DNA from sorted cells?

    Thanks for any advice!

  • Mohamed Zarka added an answer in Python:
    Is there any Python or Java code for photo/image semantic classifcation ?

    Is there any Python or Java code for photo/image semantic classifcation ?

    I am working on image semantic interpretation. And I would like to use a state of the art based source code for basic image classification.

    Mohamed Zarka · University of Sfax

    Many thanks for the answers.

    I found also a python code at :

  • Vanessa S added an answer in Metabolics:
    Is there a correlation between 1) cell size and metabolic activity specific 2) metabolic activity and MTT metabolisation ?


    1) I am performing MTT assays and was wondering how much the cell size can influence the mount of metabolized MTT?

    I thought that the amount of mitochondrial membrane, (so also the amount of active enzymes that metabolise MTT) correlates with cell size and therefore lets say 100 normal sized cells could metabolise approx. the same amount of MTT than 160 smaller cells, right?! 

    2) does anybody know if and how the metabolism of nutrients (Glucose, aa ) is connected to the activity of the MTT metabolizing enzymes ?

    As maybe the presence of nutrients at the time point of the addition of MTT !!! can influence the capacity of metabolizing the chemical .....  (I mean : 100 cells consumed a lot glucose --> remaining glucose in medium is less and metabolism goes down...so also the metabolism of MTT, ..... smaller signal,.... but treated cells, where only 50 are present consumed less Glu, therefore still more in the medium when adding MTT and therefore 50 cells can metabolize more than 50% of the MTT than 100 untreted cells) 

    Thanks a lot for reading and trying to understand and helping :) ! 

    Vanessa S · Campus IFOM-IEO

    Ok, thanks a lot !  

    I already thought it can only help me to get rough ideas about the survival ... although many labs are using it as THE method to prove the effect of a drug... 

    I also didn't know 

  • how can a programming language be selected for developing distributed systems?

    Programming languages and distributed systems have long influenced each other. Naturally, every programming language has its strengths and weaknesses. Consequently, it might be difficult to decide precisely which language should be chosen for a software project. However, the selection of the right programming language can be crucial to the success of a project or a software system.

    Jerrold (Jerry) Heyman · EMC Corporation

    Pedro Correia makes some good points.  When you describe the distributed system you wish to construct, what is meant by 'distributed'?  Running on many independent (memory/disk) nodes?  Running on many cores in parallel on a large SMP?

    Python itself is the outgrowth of the need for a distributed, multi-platform scripting language for Andrew Tannenbaum's Amoeba distributed system.  If your distributed system is just a matter of partitioning the work so that multiple nodes can process different parts of the same dataset, then the Message Passing Interface (MPI) libraries  might be an acceptable solution.  These libraries are available for C/C++/Fortran.

    Understanding the problem is key to helping determine what programming language options might be available.  Otherwise, if you start with a specific language you have the equivalent of "when the only tool you have is a hammer, all problems look like a nail"

  • Is that true that tachions were found?

    I saw a citation of an article of Robert Ehrlich, "Six observations consistent with the electron neutrino being a tachyon with mass: m2 ν_ e  =−0.11±0.016(eV)2", http://arxiv.org/abs/1408.2804. I don't deal with general relativity, but I know that even the special relativity doesn't admit faster-than-light particles. I would like to know additional opinions about this experiment.

    Vassili Perepelitsa · Institute for Theoretical and Experimental Physics

    Kinematic formulae for tachyons can be found in any popular article on the subject.

     See e.g. a paper by Gerald Feinberg in Scientific American ``Particles that go faster than light", vol.222, no.2, pp.68-73,76,77 (1970),

    or by O.M.P. Bilaniuk, E.C.G. Sudarshan in Physics Today ``Particles beyond the light barrier", vol. 22, No.5, pp.43-51 (1969).

    In fact, the whole story started with a paper by O.M.P. Bilaniuk, V. Desphande, E.C.G. Sudarshan in American Journal of Physics ``Meta-relativity", vol. 30, pp. 718-723 (1962), in which the concept of faster-than-light particles was introduced in the particle physics.

  • What is the difference between absolute and relative learning gain in pre-test post-test design ?

    Hi, I have carried out statistical analysis to assess how students performance improve from the pre-test to the post-test in control and experimental groups. I used both absolute learning gain (posttest  - pretest) and relative learning gain (posttest-pretest/ pretest). My results revealed that there is a statistical significant difference in absolute learning gain between the control and experimental groups. However, no statistical significance difference was found in the relative learning gain.

    Norman G. Lederman · Illinois Institute of Technology


    The relative gain is a proportion with the original scores in the denominator. It is similar to effect size in that it is measure of the proportion of gain. You gave me the U value, but not the actual mean scores. This is what I need. Also, the total points possible.

    How far did your sample deviate from normality, because if it was not large the statistical analysis is usually robust enough to handle it. The problem with lack of normality would be a Type I error so you can correct for this by using a more rigorous alpha level, for example.01. Also, if you can use ANCOVA it would be a more accurate comparison of the two groups.

  • Cédric Delattre added an answer in Sodium Acetate:
    Removing sodium acetate after column chromatography?


    I'm trying to remove sodium acetate from solution after column chromatography. So I have got purified organic compound (extremely hydrophilic, soluble in water) and large exccess of sodium acetate. Any suggestions?

    Cédric Delattre · Université Blaise Pascal - Clermont-Ferrand II


    What kind of column chromatography  did you use? Did you try size exclusion chromatography to desalt your organic compound?



  • Remi Cornwall added an answer in Momentum:
    Why the momentum eigen value for trapped particle in box should be two momentum eigen function for every energy eigen functioen?

    Otherwise,expectation of momentum itself is zero

  • Matej Stuhec added an answer in Polypharmacy:
    Antipsychotic polypharmacy before clozapine use OR clozapine use before antipsychotic polypharmacy in chronic schizophrenia?

    Antipsychotic polypharmacy refers to the co-prescription of more than one antipsychotic drug for an individual patient. According to the many studies consumption of clozapine in patients with chronic schizophrenia is still low (about 25 %) and antipsychotic polypharmacy prevalence before clozapine use is very high, although the evidence usually does not support its use. How to manage patients with chronic schizophrenia with higher clozapine consumption?

    Matej Stuhec · University of Ljubljana

    Hi Fidel,

    I support your trials, which you were attached, however i am interesting in medication combinations (e. g. two or more antipsychotics together).

    Anyway, it was very helpful also for me.



  • Angus Lindsay added an answer in Caffeine:
    Is the effectiveness of caffeine reduced when combined with carbohydrate?

    Hello all,

    I'm looking into the effectiveness of caffeïne, especially when combined with a carbohydrate-rich meal. I have found some evidence for this but the number of studies investigating the effect of caffeine with and without a meal is very slim. Is there anyone that could enlighten me on this subject?

    The main article that lead me on this path is an article by Tina Skinner and colleagues on the effect of caffeine in rowers. They found no ergogenic effect of caffeine, while other studies on rowers found the typical 1-1,5% improvement in power output.



    Angus Lindsay · University of Canterbury

    Hi Jorrit,

    There is quite a bit of equivocal evidence surrounding the effectiveness of caffeine and carbohydrate supplementation on exercise performance.  A 2011 review (below) for instance showed variable effects on endurance performance with and without carbohydrate and caffeine ingestion.


    A quick search will reveal a multitude of information pertaining to your question that should provide you with all the evidence you require.    Here are a few for your interest.





    So to your original question of whether the addition of CHO reduces the effectiveness of caffeine, the majority of the literature would suggest it has the opposite effect, but with a high level of variability.

    If you're wondering about the effect of caffeine alone, the below review should be able to provide you with some information.


    Hope this helps!

  • What are the various ways to store diluted paraquat for cell culture?

    I would like to store diluted paraquat for use in cell culture experiments. I believe 1X PBS would be a proper vehicle for storage at -20C. Any other advice or information about degradation?

    Christian Q. Scheckhuber · Senckenberg Research Institute

    I think it should be fine to store your paraquat solution at -20 in 1xPBS. Stability of the solution correlates positively with the paraquat concentration, so don't dilute your stock too much. For best results, however,  I recommend to prepare the solution fresh before you do your experiments.

    Best regards, Christian

  • Jack M Gallup added an answer in PCR Primer Design:
    The first point of a serial dilution to test the efficiency of my primer seems to have inhibitors, what should I do?

    I am testing the efficiency of my primers by doing a serial dilution. The efficiency is decent, but when I remove the first point it improves, leading me to think that the first, undiluted point, is too concentrated. Should I pick the next point (in this case my 1:5) as my guide and dilute all my samples to that when running them, or should I do another serial dilution to check the efficiency, but this time, diluting the first point as well?

    Jack M Gallup · Iowa State University

    Your first point is fine... keep it.  Not inhibited.

  • Paul van Erp asked a question in Spectinomycin:
    Is there a fifth antibiotic/plasmid available for E. coli, besides amp, strep kan and CAM?

    I would like to create E. coli cells that maintain 5 different plasmids, which I can select for through antibiotic resistance. Is there a fifth antibiotic that can be used besides ampicillin, kanamycin, streptomycin/spectinomycin and chlooramfenicol? Also what plasmid  would would work with that antibiotic.

  • Dinesh Saini asked a question in Ball Milling:
    Ball milling related queries for an alloy?

    If I do the ball milling of Ni50Mn45Sn5 (atomic %) for 20 hours in presence of Toluene as process controlling agent. Argon flow and vacuum were not maintained during milling.

    (i) Will the outcome alloy be a single phase or not?

    (ii) What phase (Austenite or Martensite) will form just after the ball milling? 

    (iii) If I want to go for magnetic measurements, Do I need to anneal it first? else I can go for magnetic measurements without annealing?

    (iv) If annealing is necessary then what should be the  annealing temperature and time?

  • Inbesat Khan asked a question in PDB:
    Best File of Ligands for Molecular Docking ?

    Which is the best file format for Ligand (SDF,PDB,MOL,MOL2 etc.) please provide answers why particular ligand file format is best for docking against protein in PDB format. I am using Scrodinger GLIDE for docking.

  • Marius Smistad asked a question in ArcMap:
    Is it possible to keep high resolution DEMs intact, when comparing them to a low resolution DEM?

    For my study I have six different DEMs of a glacier. The DEMs are all from different years and I want to calculate the volume changes over a timeperiod. Including the six DEMs I have one subglacial DEM with low resolution (100 meter). In ArcMap, I use raster calculator to subtract the DEMs from the subglacial DEMs to get the volume results. The problem is that the DEMs with high resolution gets converted to 100 meter resolution. Is there any way to derive results with better resolution? 

  • Mario Hirata added an answer in Trizol:
    What is the best method to isolate RNA from Streptococcus mutans or other streptococcal species?

    I am doing RNA extraction from streptococcal species. I am using trizol max bacterial isolation reagent with. i get smearing. is there any reliable method to see RNA in gel other than denaturing gel formed via formamide. 

    Mario Hirata · University of São Paulo

    I use QIgen product

    go to the website and find out

    good look


  • What is the role of IHC in differential diagnosis of salivary glands?
    Differential diagnosis is very important from treatment point of view.
    Muhammad Kamaal Khan · The Newcastle upon Tyne Hospitals NHS Foundation Trust

    Most tumours of the salivary glands will be diagnosed with simple H-E stains but there are times when IHC will be help with diagnosis e.g poorly differentiated lesion.The following article deals with this topic:

    Nagao, T., Sato, E., Inoue, R., Oshiro, H., H. Takahashi, R., Nagai, T., … Matsubayashi, J. (2012). Immunohistochemical Analysis of Salivary Gland Tumors: Application for Surgical Pathology Practice. Acta Histochemica et Cytochemica, 45(5), 269–282. doi:10.1267/ahc.12019

    Hope this helps.