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  • Cihan Civan Cıvaş added an answer in Colony PCR:
    Why non-specific band is formed in colony PCR ?

    According to agarose gel imaging, band is found in 300bp and 3000bp after the colony PCR and actually, desired gene has 300 bp. However, I do not understand why 3000bp band was formed.

    Cihan Civan Cıvaş · Izmir Institute of Technology

    I am not sure, and amplification time for this experiment is 45 second. You are right, it is not most probably amplicon. Also, annealing temperature is 72 celcius degree. I think, it is a optimal temperature for this reaction. However, already, ı do not understand why 3kb DNA found in there. I put the picture in the attachment. If you want to examine, you can examine from picture. 

  • Mariano Pierantozzi added an answer in Crime:
    Is there a bigger crime in mathematics than "divide by 0"?

    We know that not checking the value of the divisor for 0 leads to such 'absurdum' as the following 'proof':

    Let us have x=0 hence giving a true equation x=2*x which we can simplify dividing both side over x getting: 1=2 which I belie is not true :) since we overlooked to give up the division operations since the divisor (x) was assumed to be 0.

    However, the "0 division" is a kind of definite (hence "death") phenomena.  Even a very very small divisor: 0.0000000000000000000000000000000000000000001 still can be used. So, my question is if you know any other "no case" which is similar to it but evidently different in nature (no division is involved :)

    [Pls hit the green ^ if you like it]

    Mariano Pierantozzi · Università Politecnica delle Marche

    I think that it is a crime.

    When you are dividing for an unknown you're changing the domain of the functions involved. So you can't divide as you want, but you must be careful when you simplify.


  • Ahmad Bazzi added an answer in Statistics:
    When does Maximum Likelihood become sub-optimal ?

    Dear All,

    In a Deterministic Framework where we have the following Linear Model:
    y(t) = H.x(t) + n(t)
    y(t) is the observed vector of size Nx1 (we have T observations)
    H is an NxP matrix (no constraint on P, P could be smaller or larger than N)
    x(t) is a Px1 vector
    n(t) is random noise.

    It is well known that if n(t) is a Gaussian process, then you couldn't do any better than Max Likelihood, i.e. the L2 norm is optimal to estimate parameters in H and x(t). 

    My question is : when does ML become sub-optimal ? 


    Ahmad Bazzi · Institut Mines-Télécom

    Dear Ahmed,

    I never knew that, thank you

  • Gibran Esquenazi asked a question in Organometallics:
    How does one increase the volatility of organometallic clusters for CVD?

    I'm trying to use an Iron-Molybdenum cluster (FeMoC) for use in an injection CVD tool. Are there any ligands that are well known to increase volatility that I can functionalize the cluster with? Any suggestions?

  • 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

    Valentin Danci · Science

    Charles and Erkki,
    My last reply to your personal attacks: don't you worry about my education. I studied plenty of mathematics and physics in university and I've done more experiments of electromagnetism and optics than both of you have done together in your lives. Now go back to your church of relativity and scold your followers who fail to repeat exactly after you the nonsense that you preach.

  • Al Amin Rabby added an answer in Social Networks:
    What techniques, methods or tools have had better results to engage community leaders to work together on social network?

    Some of my worries in my work life is how to engage community leaders to work in social network and specially in health issues.

    according with the Arnstein ladder, some strategies and techniques could better than others but nevertheless it is not a guaranty of success. For than reason I want to know what had been your better strategies and techniques to work togheter community leaders and what was your success

    Al Amin Rabby · University College Dublin

    FGD might be useful to do that. Moreover you might open a Facebook group, if the leaders are using this social media. 

  • Angus Lindsay added an answer in Sports Medicine:
    How can I control the load in a session of Integrative Neuromuscular Training (INT)?

    Has one method specific to control the load in one training session of INT? or Can I use the known methods like: Rating of perceived Effort,  % Heart Rate and others?

    Angus Lindsay · University of Canterbury

    Hi Renee,

    Controlling the load in an INT session is the same for any physical exercise training regime.  For instance in sprint cycling, either the time spent at high intensity, distance covered at high intensity, or number of repetitions at high intensity dictate the total work-load for a session.

    With respect to INT, there are several possible options for controlling work-load.  As you mentioned, heart rate and RPE could be used but you have to keep in mind the large inter-individual physiology variability of each subject could cause significant differences in completed work.  For this fact alone, studies have pre-evaluated subjects before any training procedure is set in place. 

    You may be best to control the total amount of “work” in the session instead.  For example, maintaining the same number of sets and reps per exercise, or the total amount of time dedicated to a particular exercise; 2mins of push-ups, rather than complete 20 push-ups with no time limit.

    Below is a good example of INT used that might be of use.


  • What textbooks do you suggest for an introductory course about dynamic programming and its applications (specially, in optimization)?

    I need a textbook suitable for teaching dynamic programming and its applications for undergraduate applied mathematics students. The textbook should cover most aspects of DP specially its applications in optimization.

    Your suggestions will be  appreciated.

  • Munaif Yousif asked a question in EFL:
    Study Participants Needed?

    I am  M.A  student  at  University of  Basrah  and  I  wonder  if  there are native  speakers  in  the  group  to  help  me  with  my  test. I am  developing  a  MDCT  to  asses  pragmatic competence of  Iraqi  EFL  learners  and  I am  in  need for  British native  speaker  to check  the validity  of  the  test

  • Agnieszka Pastula added an answer in Agarose:
    How I can get spheroids after transfection of the cells as monolayer ?

    In order to obtain spheroids, I usually seed 10.000 cells per well in a multiwell 96 plate pre-coated with agarose 1%. The spheroids are formed after 24 hs. However, the cells do not form spheroids when has been previously transfected. This phenomenom is independent of the plasmid used. Could anyone suggest me some ways to solve this problem?

    Agnieszka Pastula · Technische Universität München

    Good luck!

  • Paul Carolan added an answer in Ligand:
    Any suggestions on the removal of NaCN and NaCl from a MeOH/H2O mixture containing my complex?

    Does anyone have a good idea for how to remove a large excess of NaCN from a methanol water solution containing my Fe(II) coordination complex. My complex unfortunately does not ppt but is rather soluble in MeOH/H2O as is the NaCN. I need to add a large excess of NaCN to exchange Cl ligands for CN, I have tried reducing the amount of NaCN used, but then the ligand exchange does not go well. Also my coordination complex is initially formed via a metal templation strategy and when I try other solvents the reaction does not go too well. Any suggestions/ideas would be welcome. I am templating the macrocycle with Fe(II)Cl2 and then exchanging out the Cl's for CN via the addition of an excess of NaCN.

    Paul Carolan · City College Plymouth

    Probably a completely 'off the wall' suggestion, but could you not use propanone to mop up the CN- via a cyanohydrin reaction?

  • Rebecca D Hancock added an answer in Older Adults:
    I am searching for a sepsis symptom assessment instrument for older adults. Can anyone provide direction?

    Current application of the 3 & 6 hour bundles will necessitate patients seek treatment early for sepsis.   I want to quantify the subjective symptoms of older adults with sepsis.

    Rebecca D Hancock · Franciscan St. Francis Health


    The articles from Apr-Jun 2015 Critical Care Nursing Quarterly that you referenced are very important topics in the evolution of sepsis care.  The sepsis in the elderly article provides a succinct, comprehensive review from which implications for further study are evident. Thank you.

  • Sezer Okay added an answer in Non-coding RNA:
    Can Bacteria (e.g. E.Coli) take up small non-coding RNA from their environment?

    For a small play of thoughts. I was wondering if bacteria, despite their complexe cell membrane-cell wall structures is capable of taking up miRNAs from its environment. Even if it doesn't have effects on the cell itself (as there is no RISC-silencing in Bacteria). What do you think? Is miRNA taken up in bacteria?

    Thank you already

  • Shahzad Alam Shah asked a question in Fibroadenoma:
    How much is the effectiveness of Trans Axiallary Enucleation of Fibroadenoma Breast?

    I have been doing this procedure and found it to be a feasible and effective option in selected cases and in patients that are much conscious of an incision made over the breast. Below is the link of one of my video for reference and coments.


  • Marcin Zych added an answer in Fluid Mechanics:
    How to find the velocity profile of thin liquid films in cylinder?

    fluid mechanics

    Marcin Zych · AGH University of Science and Technology in Kraków

    If you have clearly cylinder, you could use PIV.

  • Munaif Yousif asked a question in EFL:
    Study Participants Needed?

    I  am  a  M.A  student  at  and  I  wonder  if  there  are  any  native  speakers  to  help  me  with  the  my  test. I  am  developing  a  MDCT  to  assess  pragmatic  competence  of  Iraqi  EFL  learners  and  I  am  in  need  to  British  native  speakers  to  check  validity  of  the  test.

  • Khushboo Singh added an answer in Docking:
    How to stabilize a helical peptide before performing protein-peptide docking?


    My peptide is 20 residues long and it has been experimentally shown that this peptide( forms a helix in its native form) is sufficient for binding to a different protein. This peptide is attached to the other part of the protein via a loop and it is believed that this loop stabilizes the helix to some extent (the truncated helix is structurally unstable). For the experimental work, the stability of the helix is achieved by installing all-hydrocarbon staples on two residues at i and i+4 position. 

    I am trying to conduct peptide-protein docking analysis for the same. In what way/s can I stabilize the peptide before docking to achieve a good result? Your help will be appreciated. 

    Thanks, Khushboo

    Khushboo Singh · University of Houston

    Hi Pritam,

    Do you mean that the energy minimisation of the peptide should be done before docking? The reason being that I will be doing MD simulation of the complex (peptide and the protein) after docking. 

    Thanks a lot for your quick response.

  • How can i get a soil free of other pathogens while leaving only one pathogen in my case Ralstonia solanacearum?

    i need only the bacterium Ralstonia solanacearum in per kg of soil mean to say none of the pathogen is important to me thats why i only want to have a soil having only this bacterium not any other

    Christoph Kulmann · Universität Bremen

    The most reliable method is sterilization of the soil in an autoclav or oven. Then you re-inoculate it with the species you are interested in.

    Pleas mind that heat transfer in soil is often very slow, so you may need to keep your soil for some hours at sterilization temperature.

    To be on the safe side, you can put some sterilized soil samples onto agar plates to check if anything is still alive and growing.

  • Ni Ge added an answer in Special Relativity:
    Special relativity: a big Heisenberg's uncertainty principle?

    If you know the coordinates for one referential, you can only know the speed of the other. If this is true, are the Lorentz transformations incomplete? Or do they resolve the Heisenberg's uncertainty principle?


    Dear Debajyoti,

    Did you read my question about two observers (0m and 5000m) comparing pictures taken in each referentials? Because of Shapiro effect, pictures should not be the same, they still are!

    For a discussion about relativity, I propose you to read p.95/99:


    LT remain pertinent (since light is a constant), even for absence of dilation (see my picture).

  • Is the electron mass strictly of electromagnetic origin?

    There exist   theoretical evidences that this hipothesis is true, especially, it is strongly supported by the Casimir type electron stability mechanism suggested by Prof. hal Puthoff in his nice work: Putho¤ H.E. "Casimir vacuum energy and the semicalssical electron". Int J Theor Phys, 46, 2007, p. 3005-3008, as well as in the work by Valerii B Morozov,  2011 Phys.-Usp. 54 371 doi:10.3367/UFNe.0181.201104c.0389
    "On the question of the electromagnetic momentum of a charged body"

    Mohamed El Naschie · Alexandria University Alexanderia Egypt


    Scholarly articles for el naschie and inverse electromagnetic fine structure constant
    A review of E infinity theory and the mass spectrum of … - ‎El Naschie - Cited by 580
    On a class of general theories for high energy particle … - ‎El Naschie - Cited by 122
    … value of the electromagnetic fine structure constant … - ‎El Naschie - Cited by 18
    Search Results
    Electromagnetic—Pure Gravity Connection via Hardy's ...
    by MS El Naschie - ‎2014 - ‎Cited by 11 - ‎Related articles
    ... to the well known value of the inverse electromagnetic fine structure constant. ... of M.S. El Naschie's Research in E-Infinity Quantum Physics and Cosmology.
    Lie groups hierarchy in connection with the derivation of the ...
    Article: Stein spaces in connection with El Naschie's exceptional Lie groups hierarchies in high ... of the inverse electromagnetic fine structure constant from
    [PDF]Lie groups hierarchy in connection with the derivation of the ...
    by L Marek-Crnjac - ‎2008 - ‎Cited by 1 - ‎Related articles
    of the inverse electromagnetic fine structure constant from ... Similarly, El Naschie has shown that the exact experimental value of a0 is found by projection of his ...
    [PDF]Exceptional Lie Groups, E-infinity Theory and Higgs ... - arXiv
    by AA El-Okaby - ‎2007 - ‎Cited by 3 - ‎Related articles
    In this paper we study the correlation between El-Naschie's exceptional. Lie groups .... α is the inverse of the fine structure constant, (84+4k) is the field strength ...... Electromagnetic fine structure constant has been always a mystery ever.
    You've visited this page many times. Last visit: 04/11/14
    [PDF]Download PDF - El Naschie
    by MS El Naschie - ‎2008 - ‎Cited by 12 - ‎Related articles
    where ¯a0 ' 137 is the inverse of the electromagnetic fine structure constant. Noting that ... telescopic structure of the well-known Lie exceptional groups [1–4].
    E-Infinity Spacetime, Quantum Paradoxes and Quantum ...
    7 Apr 2014 - El Naschie has used E-infinity algebra to solve quantum conundrums, ..... version of the inverse electromagnetic fine-structure constant, a, ...
    You've visited this page many times. Last visit: 29/12/14
    Search Advanced Search Keywords (6) Fine Structure ...

    Mohamed El Naschie
    14 Jan 2015 - Paper From pointillism to E-infinity electromagnetism (Citations: 10) M. S. El Naschie Pretty much like in a pointillism masterpiece of say Georges Seurat or Paul ...
    Search Advanced Search Keywords (6) Fine Structure ...

    Mohamed El Naschie
    14 Jan 2015 - Paper From pointillism to E-infinity electromagnetism (Citations: 10) M. S. El Naschie Pretty much like in a pointillism masterpiece of say Georges Seurat or Paul ...
    [PDF]The Fibonacci code behind super strings and P-Branes. An ...
    by MS El Naschie - ‎2007 - ‎Cited by 27 - ‎Related articles
    level connected not only to electromagnetic fine structure constant but also the ... M.S. El Naschie / Chaos, Solitons and Fractals 31 (2007) 537–547 ... close to the integer value of the inverse electromagnetic fine structure constant a0 ¼ 1/137

  • Mona Gazzaz asked a question in Biosensors:
    What is the price materials used in prototype of graphene based biosensors detecting nucleic acids?

    I'm searching for prices for materials used in graphene based biosensors detecting nucleic acids or other biological samples (pH, electrolytes,antigens.....) using different detection techniques like electrochemical, flourecence or impedimetric techniques

  • Saeed Dashtban added an answer in Gauss:
    Newton-Raphson method and the Gauss Saydl How is the flow?

    Newton-Raphson method and the Gauss Saydl How is the flow?

    Saeed Dashtban · Khorasan Institute of Higher Education

    HI dear prashant saxena


  • Murat Ozaltas added an answer in Crop Yield:
    Which factors effect the forecasting of olive yield?

    Climate, biotic factors, pollen concentration, etc. 

    Murat Ozaltas · Independent Researcher (Olive research station)

     the long term relation between biotic and abiotic factors recorded should be evaluate in an algoritmic model.

  • What are the differences between constructivist grounded theory and classic grounded theory methodology?

    The are debates on choosing either of the two methodology approaches.

    David L Morgan · Portland State University

    The paper that Mary references, which looks at how the concept of "fit" in GT is related realism and relativism points to another difference between Charmaz and Glaser. That is her advocacy of pragmatism as a paradigm and symbolic interactionism as a broad theoretical approach. In both those regards, she is following Strauss rather than Glaser.

    Strauss' advocacy of these principles is clear in theoretical chapter that first appeared in the third edition of Basics of Grounded Theory, except it was actually written for the second edition. The importance of the distinction between the second and third editions is that Strauss died between the two, so even though the statements on symbolic interactionism don't appear until the third edition, they were actively co-authored by Strauss and intended for the earlier edition.

  • Heba Hassan added an answer in Heat Transfer:
    Does anyone have the experience dealing with earth-sheltered buildings, from the simulation aspects or the psychological ones?

    I need to find any researches about people's acceptability and reactions to live in an earth-sheltered construction.

    Another aspect, is to find a suitable simulation program which can calculate the heat transfer effect with different soil thicknesses around the building.

    Heba Hassan · Beni Suef University

    Dear Maysam,

    Thank you for this file. I passed by it, around a year ago, but didn't stop too much,

    It worth deep looking, thank you,

    I'll update you by my research outcomes,

    many thanks for cooperation,


  • How internal standard help in caliberation of GC-FID?

    do we need to inject the ISTD every time while we have to analyze our analyte of unknown concn?

    Mahesha Manjunatha Poojary · University of Camerino

    Hi, internal standard is must to calculate concentration of the unknown sample. Please note that you must 'add' an internal standard everytime into the sample which is to be analysed. Since, the peak area always varies with the amount of sample injected, finding out the response factor (area of IS/amount IS) solves this problem when you inject different volume each time. Please see attached document, how to calculate the concentration of unknown sample using internal standard method. Please note that you must also run standard compounds, including internal standard to find out conc. of unknown in the sample. 

  • Gamal Seedahmed asked a question in UAV:
    What are the key aspects to enhance the growth of the photogrammetric applications?

    Do we need to use more sensors? or

    More platforms such as UAV? or

    More applications?

  • identification
    hai please suggest any manual or method for identification for fresh water microlagae
    Muhammad Maqsood Alam · Quaid-i-Azam University

    Hi, Try this Book .... useful and informative from algae point of view... :)