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  • Can anyone help me with hibridoma cell growing?

    The medium I use is: IMDM, 10%FCS, P/S, 7.5% Sodium Bicarbonate, 0.1mM b-mercaptoethanol

    Cells double their number in 24h after thawing, but then hey do not expand more (actually the number decrease). However they look healthy and after some days start to get attached.


    Attila Lehotzky · Hungarian Academy of Sciences

    Did you change medium after plating? Or remove the freezing additive by changing medium by pelleting the cells and resuspend in fresh one?

  • Amr Shetta asked a question in Photobioreactors:
    Which is better, algae photobioreactor or phtovoltaic system for methane production?

    For methane production via CO2 photoreduction, which is better, semiconductor based photovoltaic system or algae photobioreactor system?

  • Robert Shuler added an answer in General Relativity:
    Can the light postule in General Relativity be seen in a different light?

    In General Relativity there are only two basic concepts that run the logical path to the theory.

    1) The principle of Relativity: The was first put forward in the late 1500's and early 1600's by Galileo Galilei.  It is a statement of the understanding of science to be the same for all freely moving bodies.  Einstein imbedded this in the social network of science and it seems the logical conclusion.

    2) The light postulate:  Einstein carefully crafted this definition to match what he thought about light and its unusual property of always being seen at the same speed no matter where you were or how fast you were going with respect to its starting point.       Simply: The speed of light is constant in a vacuum because the speed is independent of the source that emitted the light and therefore always constant.  This changes time to be variable.

    The implications of course where that time and space as the variants and light is the constant.

    Could not this be stated much differently?

    Gravity affects light.

    Many ideas are needed but the theories ability to calculate and or predict things traveling through space and time are not changed by these ideas.  It however does change the understanding of space and time to more closely match reality.  The twins paradox will go away.

    The affects of space are still warped by heavy objects moving through it.  Time is still affected by our ability to measure it in the presents of gravity.  

    However, it changes the perception of time being warped to time being harder to read accurately.    It also raises more questions about why we see light at this speed.  Are there simple answers to this question?  

    Robert Shuler · NASA

    Yuri & Stefano, I did not see a clear statement of anything to respond to in your comments above, even though they appear to be addressed to me and soliciting a response.  If you did want a response, say something.  :D

  • Michael F Daily added an answer in Dosing:
    Is there a life-long maximum dose for Thymoglobulin?

    I have read that ATG is a cumulative drug and the life long dose that the patient can recieve should not exceed 25mg/kg - how true is that statement?

    Michael F Daily · University of Kentucky

    I don't think anyone knows. . .

    Just recently SRTR has started collecting the the number of doses (not the actual numer of mg/kg), so I think we may have a better idea in the future.

    My bet is it is a continuous variable, like pack-yr in smoking, where you have higher index of suspicion for cancer, etc, as the lifetime dose increases.

  • Afsar Khan added an answer in HEPES:
    Can anyone tell what is the Toxicity of DMSO on cell line particularly STC-1 cells?

    We are studying effect of plant extracts and compounds on secretion of GLP-1 and GIP from STC-1 cells. some of the compounds are not soluble in HEPES buffer. So we were thinking to add DMSO yo aid in solubility. S we are wondring that how much percentage of DMSO could be used in sample preparation without effecting the cells.



    Afsar Khan · COMSATS Institute of Information Technology

    Dear Hammad

    You requested for a paper on Alnus nitida. That paper is not open access but copyright material that is why I can not upload it. My e-mail address is afsarhej@gmail.com. Please send me an e-mail.


  • What are the applications of super critical fluid?

    Hello all

    I have seen articles where in they have discussed challenges to study near critical fluids especially moving about the critical point, from super to sub critical fluid. 

    Will some one elaborate on applications where the study of moving about critical point may be useful. The super-critical CO2 has been mentioned to have several uses in chemical processes. However that addresses mainly the chemical properties of the super critical CO2. 

    What I am looking for is where one would be able to apply heat transfer study mechanism of super critical fluids. 

    In other words what are technological applications of super critical fluids .


    Thanks all

  • Attila Lehotzky added an answer in MIKE Software:
    Uncommon FACS construct?


    At the moment I'm dealing with the detection of my expressed protein. I already have an primary antibody against this protein (purified form) for ELISA where  I'm using a Protein-A-HRP conjugate system. Now I want to follow the expression of the membrane bound version of this protein via FACS. 
    Because I also have an Anti-HRP sec Antibody, I'm wondering if FACS will work when I use this one against the HRP of the Protein A-primary Antibody construct?

    thanks for your help


    Attila Lehotzky · Hungarian Academy of Sciences

    Simple: no. You need a fluo secondary against your first antibody.

  • Md Equbal Ahmad added an answer in Aphids:
    How the plants of the same genus effect the feeding potential of insects specially to aphids?

    Prof. Rajendra Singh

    Md Equbal Ahmad · Tilka Manjhi Bhagalpur University

    nutritional value, secondary chemistry and morphology of plants

  • Why does dilution of homoeopathic medicines enhance their potency? Is this not against scientific phenomena?
    I have been told by homoeopathic practitioners that dilution and potency of homoeopathic medicines is inversely proportional. This means the higher the dilution the more potent the medicine will be and vice versa. I have doubts which may be due to my bias because personally I did not find any experience of homoeopathic medicine effective.
    Barry Turner · University of Lincoln

    Since the water on earth is subject to a cycle of evaporating from the oceans, falling as rain, percolating though the earth and returning to the oceans via the rivers it must at some stage have picked up every toxin, virus, bacteria and prion in existence becoming the perfect solution.  Since it will have been very rigorously succussed in fast flowing rivers and sea currents than all hate must contain every homeopathic remedy there is.  

    Why is it necessary to add more micromolecues when it is already there?

  • Does anybody have experience in dimensioning aerostatic and/or magnetic bearings?

    We are developing a device that must run at 100.000 min-1, with frictionless bearings. Thanks a lot for any contribution!

  • How to distribute pressure along the surface of the aerofoil from body force values?


    I know that from the pressure distribution the body forces can be calculated. But if the body force is known, how to distribute the pressure along the aerofoil surfaces.

    Ijaz Fazil Syed Ahmed Kabir · Nanyang Technological University

    hi Sorry this is not my required 

    Cp plot vs chord. I calculate Cn

    Now from Cn I need to plot Cp vs chord

  • What advantage of international division of labour will contribute to physical cross-border regional development?

    Cross-border regional development

    Richard Croucher · Middlesex University, UK

    I'm sorry Choen, I think we could try to help better if we understood the question better because I do not know exactly what you mean by this question. 

    Can I suggest you give us an example of what you mean and what your hypothesis is?



  • Tina Leisner added an answer in Western Blot:
    How can I eliminate additional bands in my Western Blot?

    Dear all,

    I have got problems with my Western Blots.

    I try to detect the LDL - receptor. For this, I use an AB from Biovision (http://www.biovision.com/ldlr-antibody-1296.html), where I expect a strong signal at 130 kDa and additionally between 55 kDa and 70 kDa.

    And indeed, I can see these bands in my Blot.

    But the strongest band, which I can observe, is an additional band at the height of approx. 30 kDa and I don´t know, what this band stands for.

    I used different dilutions for the first AB (mainly 1:500) and for the second one (mainly 1:20.000).

    I also started a Blot, where I incubated the membrane only with the 2nd AB, to see, if this AB is unspecified.

    But in this case, I received an empyt Blot. 

    Do you have any suggestions, how to eliminate these additional bands?

    Best regards


    Tina Leisner · University of North Carolina at Chapel Hill


    It's not surprising that you saw the same bands with abs from different companies.  If you are running reduced samples you will likely see the same pattern.  Before trying MALDI-TOF, I would re-run samples that have been prepared under non-reducing conditions.  That would certainly be much easier. 

    Also, I dilute my antibodies in TBS-T with either 5% milk or 5% BSA, depending on the protocol for that antibody.  I always dilute my secondary antibodies in TBS-T with 5% milk powder.

  • Taher Rabizadeh added an answer in Gypsum:
    What does a decrease in FTIR peaks intensity show?

    I analyzed two kinds of powders (gypsum, gypsum+additives) by FTIR (attached file). There is decrease in peaks intensity and absorbance. What does it show? Can it be just because of the amount of powders I used while analyzing?

    Taher Rabizadeh · University of Leeds

    Thanks for your answer. Can it be related to the amount of samples I used for analysis? I mean in one case I put lots if samples under diamond probe than the other case.

  • How can I do western blotting in tendon?

    Somebody could give me a protocol of western blotting to collagen type I and III of tendon? I can't extract anything proteins.

    Thank you so much.

  • Chang-Er Chen added an answer in MassLynx:
    How can I set the scan times for MRM in masslynx?

    Hi everyone, 

    I am doing MRM on our Micromass API MS.

    I am wondering how should I set the scan times, like inter-channer delay, inter-scan delay and dwell time? any tips for these settings? I am using both negtive and positive for about 40 chemicals.

    I am a bit confused by these times?

    many thanks.

    Chang-Er Chen · Lancaster University

    Hi Daneil, I tried setted the scan time as the paper did:

    dwell time 0.01s and ISD 0.02s, but I still got bad peak shap. (see attached).

    seems too small?



  • Maykel Manawan added an answer in Fullprof:
    How to rietveld XRD powder pattern by Fullprof or GSAS?

    I am studying in SrTiO3. However, I do not know how to Rietveld the crystal structure of the sample. Anybody can help me? Thanks.

    Maykel Manawan · University of Indonesia

    So sorry for that .par file, u need to hit the refine button to get the same result. I attached the picture of different intensity.

    Anyway, I send the complete MAUD files and the last 2 refinement files, i skip the one with systematic error. Cud u please take the SRM scan at the 1st instrument (operator: IPE).

  • Farhad Karami added an answer in Strawberry:
    Any suggestions on seed germination on Strawberry fruits? Why did this happen?

    I took this pictures in a greenhouse near Sanandaj, Iran, yesterday(5/17/2015), Seed germination on strawberry fruits, preharvest! Why this happen?!

    Farhad Karami · Buali Sina University

    Dear Professor Guido Bongi,

    Thanks for your advise.


  • Attila Lehotzky added an answer in Mycoplasma:
    Can anyone suggest the treatment steps if mycoplasma positive is found in biological samples e.g: FBS, Trypsin, Cells, Virus etc.?

    What should we do to eradicate mycoplasma presence from our lab and samples? 

    Attila Lehotzky · Hungarian Academy of Sciences

    Plasmocin can be use too as preventive agent in low concentration.

  • Julien Jean Malard added an answer in Pest Control:
    What can be the appropriate solution to white flies in pawpaw??

    the white fly as the pest affecting pawpaw fruits.

    Julien Jean Malard · McGill University

    On the biological control side, I believe that insecticides containing neem extract or the fungus Beauveria bassiana would be effective.

  • Abdelkader BOUAZIZ added an answer in Formic Acid:
    Does anyone know about polyamide 66 (Nylon66) Hansen solubility parameters (HSP)?

    There are different values reported in the literature!

    The strange thing is that formic acid is an excellent solvent for PA66, but all the reported HSPs are far different from those for formic acid. The R-value (gyration radius, dissolution distance) for formic acid with respect to reported PA66 HSPs is even greater than two, but it dissolves PA66 readily! While, regarding HSPs, it should not dissolve!

    Any explanation/suggestion?

    Abdelkader BOUAZIZ · Univ. Ibn Khaldoun Tiaret

    sorry, I forgot the following link:

  • Ananth Saradhi added an answer in Silvaco:
    How can I obtain the photon/exciton concentration as a function of position in Silvaco ATLAS ?

    What is the command/syntax to obtain the photon/exciton concentration as a function of position(x, perpendicular to direction of incidence(y)) in Silvaco ATLAS in a given organic material?

    The light is assumed to be incident vertically on the photo-active material ( Organic )

    The use of PROBE statement gives me the value at one specific location. What do I do to get a profile of the exciton/photon concentration along the x direction( perpendicular to the direction of incidence of light)?

    Ananth Saradhi · Birla Institute of Technology and Science Pilani

    Dear Craig,

    Thank you for your pithy response. Could you kindly point to the relevant  sections/ examples and help me out. I did not know that cut-lines are used for profiles. Thanks  for the prompt response.

  • What are the possible problems of Hanover authentication protocol in vehicular Ad hoc network (VANET).?

    Investigating on pair-hand authentication protocol in WAVE. 

  • Apurva Kumar added an answer in Blood Glucose:
    Is there a way to measure blood glucose level non evasively? What are the methods we can use to measure it ?

    We are expecting to find a method to measure blood glucose level non evasively in a research level.   

    Apurva Kumar · National Institute of Mental Health and Neuro Sciences

    I have heard of non invasive glucometers. Don't know how well they work. Do u need one for rodents? Then I wwould be skeptical. 

  • Does svm kernel increase the dimensionality?

    Does svm kernel increase the dimensionality or not.

    Benammar Riyadh · Université Jean Monnet


    I have just asked my teacher about this question :) . He said to me that It depends on the context. In general the Kernel increase the dimension but "implicitly". In other way It increase the dimension without increasing the running time (this is the benefit of the kernel use).
    I hope that I'm on the good way this time.

    My bests,

  • Is there any reference/ methods/rules to understand about the minimum number of observations needed for ANN based data prediction?

    Hello Everyone, I am working on data prediction using ANN method. I need to know, is there any specific rules/references/ mathematical formulas to understand the minimum number of observations required to apply ANN techniques to predict a data. Note that, I have 80 observations of soil properties (14 variables) to predict SPT value. Can I get any Idea?

    Murugan Solaiyappan · Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ

    The following link may be useful for you.


  • Oliver Burdekin added an answer in ArcMap:
    How to edit Maxent output with ArcGis?

    I ran the maxent analysis and then imported it to be able to edit it in ArcGis.
    The file I imported is the median output of 100 repetitions bootstraped.
    The problem is that when I import the csv file to ArcMap they don't match the actual points in the distribution map. 
    I was told it is a projection issue, but I can't figure how I can correct it. Does anyone know how to do it?
    Also, when I imported it to ArcMap the legend disappeared. How can I show it aside the map?
    Thanks in advance!

    Oliver Burdekin · burdGIS

    I think you'll need all of them. Keep in mind that you're just pointing MaxEnt to the directory that holds them all. And if you're spanning 8 years, are you sure you want to be projecting them as a whole? Would it be better to make a model for one year and then see how changes over time affect the prediction? We might need to move this to email and / or skype Yussuf, which I'm happy to do. :)

  • May gravito-electromagnetism be an alternative to Einstein's theory of general relativity?

    Gravito-electromagnetism (GEM) describes gravitation starting from the idea (suggested in 1893 by Oliver Heaviside and further developed by Olev Jefimenko) that there is a formal analogy between the gravitational and the electromagnetic phenomena.  This implies that - relative to an inertial reference system O - a gravitational field is characterized, in analogy with an electromagnetic field, by two vectorial quantities: the gravitational field Eg and the gravitational induction Bg.  The spatial mass destribution is the source of Eg  and the motion of the masses relative to O that of Bg

    According to GEM, a gravitational field is just like an electromagnetic field (Maxwell's equations) mathematically described by a set of four partial differential equations, the GEM-equations.   They describe how Eg  and Bg   vary in space due to their sources and how they are intertwined.  The action of a gravitational field on particles is described by a law analogous to Lorentz's force law: the force law of GEM.

    It has been shown that GEM can explain a number of phenomena (precession of planets and binary pulsars, gravity probe B experiment, ...) that are inexplicable in the context of Newton's description of gravitation what makes that GEM can be considered as a possible alternative to GRT.

    In line with the original idea of Heaviside GEM can be seen as an extension and a refinement of the "classical theory of the gravitational field", an extension that - besides the effect of the spatial distribution of the gravitating bodies - takes into account the effect of their motion.  GEM can theoretically be founded and explained by the theory of informatons. (https://www.researchgate.net/publication/268576021_GRAVITO-ELECTROMAGNETISM_EXPLAINED_BY_THE_THEORY_OF_INFORMATONS?ev=prf.pub)

    Let us still mention that GEM has been discussed within the context of general relativity by a number of authors and that it has been shown that  the GEM equations can be derived in the weak field approximation of Einstein's description of gravity.

    Thierry De Mees · General Science Journal

    I am afraid that these pages are just becoming an ordinary forum about all sort of things. The original question was: "May gravito-electromagnetism be an alternative to Einstein's theory of general relativity?".

    My answer is: definitely, YES. The reason is that it explains much more than GR:

    - How does it happen that the solar system is almost flat?
    - Why do all planets revolve in the same direction around the sun?
    - Why are Saturn's rings shaped as they are?
    - Why are also some galaxies flat?
    - How does come that all stars of flat galaxies rotate with approximately the same speed about the central bulge of the galaxy?
    - Why the age of disc galaxies is much more than the windings of the spirals show?
    - Why can fast rotating stars rotate that fast without exploding or falling apart?

    Furthermore it explains:
    - The double bending of light and gravitational lensing.
    - The Mercury perihelion advance.
    - How large the mass of heavy, spinning stars and black holes really is.
    - The longer lifetime of fast mesons.
    - The absense of huge amounts of dark matter.
    - The results of the Gravity Probe B experiment.

    and much more. See link below, click "Download and read it now" for a free download.

    In fact, GR has proven almost nothing of this list, and the "improved" theories based upon GR, are imitating gravitomagnetism more and more...