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  • Charandeep Singh added an answer in Yeasts:
    Why is yeast strain Y258 used for protein expression in yeast?


    Is there any specific reason to use Yeast strain Y258 for protein expression in yeast. 

    Is it not possible to express protein in BY4741 yeast strain? 

    If it is not possible to use BY4741 yeast strain for protein expression, then why is it not possible. 



    Charandeep Singh · University of Luxembourg

    Dear Philippe,

    Thanks a lot for your answer. Now, I am very motivated to follow on with protein expression in standard yeast strain we have in our lab.

    Kind regards,


  • Serban C. Musca added an answer in Herbicides:
    What statistical analysis should I use to compare the rate of dandelion suppression using 3 different dosages of herbicide each over 3 applications?

    The research question is to determine the optimal dosage and the correct number of applications of a herbicide to control turf dandelions. Each of the 3 different dosages are going to be applied to the same plots once per month for 3 months using a complete randomized block design.  I'm aware that its likely a anova analysis as the dependent variable,dandelion suppression rate, is a continuous numerical variable and the independent variables, the several different dosages of herbicide , is a nominal categorical variable. How would I go about using the anova analysis to answer the question though? Is there a more advanced anova analysis that I am not aware of? 

    Serban C. Musca · European University of Brittany

    @Jochen: As always, a pleasure to read your input !!

    @Michael: I have to compliment you for asking yourself (and the RG community) the good questions BEFORE you do your experiment (Wish my students did the same more often...) Good luck with your experiment !

  • Aharon Wanszelbaum added an answer in Telemedicine:
    Is Telemedicine part of information sharing ?

    Anyone can provide me a reference prove that telemedicine ia a part of information sharing 

    Aharon Wanszelbaum · meuhedet health service

    Telemedicine is really a very vast field so that you should frame your question more specifically.

    This said obviously there is no point of telemedicine if it does not allow sharing.It may be restrained partially if so needed or comletely open to the doctors and other caregivers/

    But one of the greatest things is the information sharing going along with quick and swift responsiveness without undue time wasting in appointments and transportation.

    It is simply put life saving

  • Rakesh Ganji added an answer in LC-MS:
    How to find statistical significance for qualitative proteomic data?


    I have proteomic data from LC-MS of three individual experiments. IIt is a qualitative data. I have grouped the proteins into the number of they are identified from three experiments. For example, if a protein appeared in all three expts, i give a value of 3 and if in two expts then 2 and so on. Can anyone please suggest a method to calculate the statistical significane for the list of proteins. 

    Thanks in advance.

    Rakesh Ganji · University of Hyderabad

    I had two conditions. For each condition, I have three biological replicates (Experiments). So the proteins identified from three experiments for a condition are grouped into number of times they are identified out of three experiments. So I have list of proteins for two conditions separately from three experiments per condition.

    I have identified the proteins from LC-MALDI-MS. The objective is to look at the differences in the proteins between the two conditions.

  • Does anyone have experience on collecting plant volatiles outside the lab?

    I would like to collect volatiles of barley plants in the field and am concerned that bakground volatiles will complicate the analysis of my samples. I appreciate advice on best methods.

    Marta Giner · Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria

    See here an other example:


  • Ravi Ananth added an answer in Crystallinity:
    Where can I get information about Roland's Method to get crystallinity from XRD Pattern? Is it valid for XRD patterns of polymers also?

    I need information about Roland method to get crystallinity from XRD pattern.

    Ravi Ananth · Onsight Technology USA

    Cannot open the above file type? Use PDF if possible.

  • If you had to participate in a RCT on plasma transfusion in critically ill patients, what trigger would you want to use?

    When randomizing patients to two different plasma transfusion strategies, it is important to make sure the coagulation test used to differenciate both groups makes clinical sense.

    Would you use INR (not designed for non-AVK patients but very commonly used), TP or aPTT ratios (more complicated to use are different tests yield different results), or ROTEM or TEG (not evaluated outside the massively-bleeding patients, and not often available)?

    Roger L Royster · Wake Forest School of Medicine

    The INR of plasma is 1.4 to 1.5.  Giving plasma with the INR in that range is worthless. With the help of our hematologists we developed a protocol for cardiac surgery patients in which we give 1 unit for an INR of 1.5 -2.0.  2 units if the INR is 2.0-2.5 and 3 units if the INR is over 3.0.  For higher INR we give Prothrombin Complex concentrates because of the value issue with additional plasma.  There is some good data related to INR elevation and degree of factor deficiency which supports the above protocol. We've found the use of TEG and ROTEM is also worthless.  Our senior hematologist says that no in vitro test can predict in vivo coagulation any better than our regular coag tests and they have their limitations as well. We have do not have a TEG or Rotem in our institution.  Several papers recently support this and the Society of Cardiac Anesthesiologists had a panel discussion on TEG and Rotem and essentially said the same.  We should not be basing any clinical decisions on the results of a these devices.

  • Antonio Bolufé-Röhler asked a question in Covariance:
    In a Normal Multivariate random variable, what is the average distance between the sampled points and the mean of the distribution?

    More specifically, Let μ and σ be the mean vector and covariance matrix of a Multivariate Normal random variable. What is the relationship (function) between the norm of σ and the average distance between the sampled points and μ? Any other relationship between the average distances and any other metric of σ could also be useful.

  • Mangilal Choudhary asked a question in Electron:
    Is it possible that the electron - electron interactions in the potential well change the energy too much in plasma ?

    if electron populations are trapped in the potential well, created in the plasma by any instability. how these electrons get detrapped in weakly collisional regime?. what will happen when these electrons interacts with higher ( 50 - 60 ev) and lower (3-5 ev) energy electrons?. will be possibility for change the energy too much so that two groups of populations appear in the plasma system? please tell me possibility.

  • Jean-Francois Antoine added an answer in STAMP:
    Tolerance capabilities of differents metallics manufactures processes?

    I'm looking for a table that show the normal tolerances for the differents metallics manufactures processes? For example: machining, forging, casting, stamping?

    Jean-Francois Antoine · University of Lorraine

    Some informations that I have used to improve the information provided to students, few years ago. This is draft documents where numbered informations should be exact.

    They had been published on the web.

    More recent versions should exist directly from ISO.

    Yours sincerely,

  • How do you extract citations from an article and export the result to a reference manager?

    How do you extract citations from an article and export the result to a reference manager?

    If you find a great artcile and want to build a References list based on that article (e.g.) review hwat Tools are available as of today?

    Nicolai Hermann Jørgensen · Norwegian University of Life Sciences (UMB)

    Thanks Kami, i did that, but that should be less cumbersome and a feature in most Reference managers. Maybe in the near future. But thanks again.

  • Chiqian Zhang added an answer in Biodegradation:
    What is the procedure for calculating COD after biodegradation and what should be blank for calculation?

    Can anyone provide detailed method for COD calculation after biodegradation of effluent sample and which kind of blank should be use for this? 

    Chiqian Zhang · University of Missouri

    0.45 um mambrane is a good option while the issue is that it is very expensive. Is that possible we just use a paper filter for the filtration work? 

  • Is the cancer cell triggered to divide as a consequence metabolic disequilibrium?

    Recent research suggests that there may be a close relationship between the likelihood of developing certain types of cancer and quantifiable changes in the dynamical behavior of cell metabolism consequent upon inheritable mutations in mitochondrial DNA.This begs the question as to the relationship between metabolic disequilibrium and cell division that might suggest alternative strategies for the prevention and treatment of cancer.

    If it can be shown that cell division is primarily triggered by instabilities in the cell's overall dynamical behavior consequent upon it being unsuccessful in finding a 'metabolic solution' to its' environmental boundary conditions then a possible alternative approach to the treatment of cancer would be the identification of the root cause of the metabolic instability followed by a treatment to rectify it. 

    Stagnaro S., Caramel S. The role of mitochondria and mit-DNA in oncogenesis, Quantum Biosystems. 2010, 2, 221-248, 2010.

    Huang paper is making interesting analogy.  Because of cancer cells quick adaptation, it appears that the best defence against it  is the immune system which also has an ability to adapt.

  • Good books on culture of tissues to recommend?

    I have to give a class to Master students on culture of tissues (not tissue culture know as culture of cell lines or isolated primary cells, but animal and plant tissues). I know only the basics and have experience only with culture of cells not whole tissues. Do you have a good book to recommend me that I could use to create my class? Thanks sincerely.

    Sandra L López-Vergès · The Gorgas Memorial Institute for Health Studies (GMI)

    Hi Semith,

    Thank you very much. Best, Sandra

  • Daniel Wright added an answer in Memory:
    Is the memory of a dramatic personal event an autobiographical episodic memory only or can it be characterized as a flashbulb memory as well?

    Suppose you can vividly remember every single detail surrounding a dramatic PERSONAL event: where you were, who you were with, what you were doing, who told you, how you felt, what happened afterwards, etc. Is that only an autobiographical episodic memory, or is it also a flashbulb memory, even though it refers to a PESONAL event and not one of historical importance?

    Daniel Wright · ACT, Inc.

    Brown and Kulik included personal events in their 1977 paper. A few authors restrict FBs to shared events saying FBs mark the intersection of the public and private (or to place oneself in history). It depends how you define FBs. A problem in the FB literature is people sometimes using different definitions of FBs and sometimes the methods that they use not matching onto how they describe FBs in their introduction sections. See the attached.

  • Fertahi Sayfdin added an answer in FLUENT:
    What is the swept area of a Darrieus wind turbine ?

    Dear readers, what is the swept area of H-Darrieus wind turbine,to use in "Fluent", that connects three Naca blades  ? I read that it's equal to 2/3*hydraulic diameter, but it doesn't give an accurate results .

    Fertahi Sayfdin · Université Moulay Ismail

    Thank you M.Rakesh. Could you please send me the publications that I requested.

  • Satwinder Singh asked a question in Glass Ceramics:
    Why the Raman peaks in glasses show decrease in intensity or cease to zero with increase in modifier cations?

    Glass ceramics generally have well defined Raman peaks in Raman spectrum. However with the increase in modifier content, I observed that intensity of the peaks decreased and ceased to even zero with further modifier content increase. Is is related to the exploitation of center of symmetry of glass network, or some other phenomenon is contributing to it???

  • Ian N Oyaro added an answer in CLC:
    Is there a way of increasing the number of the query matches in a CLC Bio blast output?

    I have been blasting against NCBI using CLC Bio genomic workbench.
    Since my samples have more than one query sequence, the default view of the summary table i see is whereby only the description of the top match for each query sequence is shown/reported.

     Is there a way of increasing this view, to let say, the top 5 matches? So that the blast output table has the top 5 best matched sequences to my query sequence?

    Ian N Oyaro · KEMRI-Wellcome Trust Research Programme

    Thanks alot.

  • András Bozsik added an answer in Renaissance:
    Does anyone know who the artists are the first to introduce contra (inverse)-perspective in painting art?

    Whether it happened before or after Renaissance time?

    András Bozsik · University of Debrecen

    Dear Christopher,

    Thanks for your detailed analysis of the pictures I formerly presented. I think even the first two but mainly that of the Middle Age are artworks. The subject as devotion or religious feeling does not decrease the will and desire to express something very important in that time. The task of art has been always to approach the ideals and truth people considered as those in that time. The Braques picture is really difficult to observe and to recognise the lines of objects because the reflections of the artist represent here broken pieces observed from various points in order to give the appearance of a three dimensional view. Chagall presented his remembrance of his Ukrainian home village, the world of poor Jewish people without respecting the rules of formal perspective. This is really similar to a dream-world where perspective does not matter. Leger similarly to Braque broke the lines of the naïve view and tried to build a constructive picture of geometrically reduced forms. The formal perspective has been also only partly respected.

    And now here you are Les domoiselles d’Avignon of Picasso. This represents a view regarded from mildly altered viewpoints, thus lines of classical (renaissance) perspective were broken as well.

    I am sorry, I am so late but I paint more and discuss fewer.

  • Hieu Trong Tran asked a question in Photo:
    How to design a good Transimpedance amplifier (TIA)?

    Hi everyone,

    Which topology is the best one to design for Transimpedance amplifier (TIA). I need a good one to amplify photo diode with current as low as 50uA. Can anyone suggest me with any idea? 

    Thanks in advance.

  • Is it worth publishing with Lambert Academic publishers?
    My inbox has repeatedly been spammed from lambert Academic publishers. Is it worth publishing with this publisher. Do they have any authenticity. There is a lot of bad stuff written about this. Still, people publish their thesis with them. How one could publish your results in the form of book when its already published in the form of research articles. Are they peer reviewed....Suggestions welcome

    Lydia Akinyi Omuko · University of Strathclyde

    Thank you for this, just received an email from them today and was doing my background check then I found this.

    Dear Ms. Lydia Akinyi Omuko,

    Are you the author of work entitled 'The Role of BRICS in Future Climate Change Regime: Why Their Commitment and Participation is Important and How to Achieve it'? I found its reference in the archive of University of Strathclyde.

    I’m Nicolae Marinciuc from the editorial team of Lambert Academic Publishing. We believe this particular topic could be of interest to a wider audience and we would be glad to consider publishing it. We are especially interested in publishing a complete academic work of yours (a thesis, a dissertation or a monograph) as printed book. Our services are free of charge for authors.

    Ms. Lydia Akinyi Omuko, would you agree to receive more information in an electronic brochure?

    Thank you in advance.

    Kind regards/Freundliche Grüße

    Nicolae Marinciuc
    Acquisition Editor

    LAP LAMBERT Academic Publishing is a trademark of:
    OmniScriptum GmbH & Co. KG

  • Shuang Zhu added an answer in Real-Time PCR:
    In RT-PCR, only one peak occurs in negative control with only primers?

    I ran a negative control with only primers in RT-PCR, but one significant peak occurred in melt curve. Then i tried running it with cDNA, the peaks in negative control is lower(Tm) than peaks with cDNA sample.

    In attached files, 'negative control' contains only negative controls with two primers. and in '050215-testify with negative control', the first line(Line A) are negative controls, and second line(Line B) are with cDNA samples.

    The sequence of every primers are showed in 'primer sequence' file. And the amount of reagents are showed in 'experiment info' file.

    Thank you very much!

    Shuang Zhu · Seoul National University

    Dear Benjamin Gantenbein,

    Thanks for your help. Actually im thinking the same that a primer-dimer formation happened. But i checked on internet that usually if a primer-dimer forms, there should be two peaks in melt curve.. So im kind of confused.

    But still wanna try to lower the conc. of primers to see if primers will still react with themselves or not.

    Thank you again for your reply.

    With regards, 


  • How can I use Minkowski functionals to to help me evaluate porosity?

    I have a ceramic coating and want to characterize its porosity. It has oriented porosity, as well as some cracks.

    I have SEM photographs, but I have some difficulties in processing the images. Part of the problem is that it is difficult to prepare the samples: I get some edge rounding. The other is that I have limited access to the SEM, and cannot take a lot of micrographs. Plus when I do, it is hard to take really consistent micrographs.

    I'd like to be able to determine things like: total porosity percent, aspect ratios of pores/cracks, and pore size distribution.

    I've used ImageJ, but it is hard to get consistent results. I was hoping to use Minkowski functions to address some of these issues.

    I have been trying to use some MATLAB routines, including Professor Legland's excellent collection. But I haven't figured out how to use them to solve my problem: perhaps the problem is I just don't know how to process the results.

    If there's a good paper or textbook that I should read that would be great too.

    Thanks for any help.

    Hamida Mohammed Bakr Darwish · King Abdulaziz University

    If use AFM tech. look for the 3D images it will be clear for the porosity state. For processing Minkowski Functionals Please look for this Article may help you.

    (Efficient processing of Minkowski functionals on a 3D binary image using binary decision diagrams
    LICN–IUT, Universite ́ de LIMOGES Alle ́e Andre ́ Maurois
    87065 LIMOGES CEDEX, FRANCE isabelle.blasquez@unilim.fr
    J.-F. POIRAUDEAU LICN–IUT, Universite ́ de LIMOGES Alle ́e Andre ́ Maurois
    87065 LIMOGES CEDEX, FRANCE poiraudeau@unilim.fr

    At this website {http://www.unilim.fr/pages_perso/isabelle.blasquez/Blasquez_WSCG03_3ADD.ps}

    hope is very good for you 

  • Daniela Gogova added an answer in Superalloys:
    Raman Spectra for YSZ thin films on Ni based superalloy having a peak at 715 cm-1, How can I identify it?

    Dear Researchers,

    I have a raman spectra for YSZ thin films on Ni-Superalloy, I got a peak at 715 cm-1. I went through some of the journals no one reported peak at 715 cm-1. I took raman spectra for diff mol% of YSZ thin films, the presence of peak at 715 cm-1 is same in all spectra with same intensity. Kindly help in this regard.

    Daniela Gogova · Central Lab of Solar Energy and New Energy Sources at the Bulgarian Academy of Sciences

    Yes, Dr. Yesudhas has given the right idea.

    Make a measurement of the substrate also.

  • Shahram Moradi asked a question in Electromagnetics:
    Displacement of Electromagnetic components on crystal?

    Why in the crystal : the perpendicular component of the displacement field must be continuous across the dielectric boundary, but the parallel component need not be?

  • Akira Kanda added an answer in Space Time:
    Do objects move in relation to space-time in GR?

    Generally sympathetic to Carlo Rovelli's pronounced "relationalism" regarding space and time, I still find some of what he says about this puzzling. This question seeks clarification. He argues, in his paper "Localization in QFT," (in Cao ed. Conceptual Foundations of Quantum Field Theory, 1999, p. 215, that "General relativity describes the relative motion of dynamical entities (fields, fluids, particles, planets, stars, galaxies) in relation to one another." This seems true enough. But this is supported by the idea that space-time itself in GR is a "dynamical object," which curves or changes by relation to mass and energy present. But that does not seem a reason to hold that objects do not move in relation to space-time in GR. Instead, it seems that the gravitation field (which determines space- time) is one of the things in relation to which objects move, and consequently that objects move in relation to space-time in GR. In spite of that, Rovelli can be found to say, on the same page, that "Objects do not move in respect to space-time, nor with respect to anything external: they move in relation to one another." Is it inconsistent to think that if objects move in relation to one another, then they move in relation to the encompassing space-time?   

    Akira Kanda · University of Toronto

    Stephano, there is no such thing as wave whose magnitude is relative to the magnitude of the receiver of the wave. Em wave is not reality. It is ficticiuos. This is the source of all problems we have now. We do not know what light is. If light is reality, definitely it is not em wave.

    But whatever it is if it moves with speed c in vacuum then the argument I made kicks in .

  • Virtual museum collections of skeletal material?

    Hi folks

    I wonder if any of you have experience working with Virtual museum collections of skeletal material?I'm familiar with Digimorph and I use it for teaching.  Are there others that you use, and particularly are there any working at the population level with multiple examples of each species?

    Thanks everyone.


    Jens Carl Dieter Kosch · Freie Universität Berlin

    Another great collection of digitalised vertebrate skelttons (including fossils) is MorphoScource:


  • Mojgan Mirzaei added an answer in Water Pollution:
    Can anyone recommend a model to evaluate the fate of pollutants in soil or water?

    Hi, I am looking for a model to evaluate the fate of pollutants in soil or water. Do you know any model for this purpose? And what information is required for this topic?

    Mojgan Mirzaei · Malayer University


  • David Arthur Carlson added an answer in Syringes:
    Any recommendations for a colour dyed leak detection tracer gas?

    I am having issues creating a carbon dioxide calibration curve. My method involves transferring CO2 gas from a canister to a gas sampling bag and then to vials with septa caps containing a detector using a GC syringe and needle. I am not getting any colour change on my detector wells and suspect that this is due to leakage somewhere in the transfer process but need to test this. Does anyone know of a way that I can do this/a supplier to contact in the UK? I was hoping to find a coloured (but harmless) tracer gas to run the process with but am not sure of suppliers/what exactly I am looking for.

    David Arthur Carlson · University of Florida

    I had a lot of trouble with CO2 storage in my large Teflon bags--found that the bags were permeable to CO2!  Even the small amounts of CO2 present in human emanations got wobbly.  Use a CO2 sniffer? We had an old Mine Safety device for low levels of CO2 --1971.

  • Jont B. Allen added an answer in Analytic Function:
    Is the function g(z) = f(sqrt(z)) analytic?

    Suppose we have an analytic function f(z) of a complex variable z and that its Taylor expansion possesses only even order terms. Is the function g(z) = f(sqrt(z)) analytic?

    Jont B. Allen · University of Illinois, Urbana-Champaign

    Yes it is analytic except at z=0. So I'm not quite in agreement with the answer by Joel Feinstein (previous comment). Here is how to settle this question: Do the integral around z=0 at a fixed radius, with the angle varying from 0 to 2pi. If the function is analytic at z=0, then that integral will be zero (Cauchy integral theorem).

    It does, however, have a branch cut that goes from zero to \infty.

    Of couse all this depends on what the function F(sqrt(z)) is. If F(z) = 1/z, then that raises a whole new set of problems.