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  • Rachid Rouabhi added an answer in Glutathione S-Transferase:
    Is there any simple method to compare GSTm and GSTc?

    is there any simple method to compare GSTm and GSTc?

    Rachid Rouabhi · Université de Tébessa

    thank you friends

  • Wolfgang Geithner added an answer in Radiative Transfer Modelling:
    Which software i can use to calculating of Radiative Transfer Model?

    I want calculating atmospheric gas in my PhD thesis.

    Wolfgang Geithner · GSI Helmholtzzentrum für Schwerionenforschung

    Dear Sajad

    Well - I am not familiar with MODIS data, but I took a look at its Wikipedia description and as far as I can figure from this information these data are mostly images in different spectral ranges. I believe that Mathematica can help you it comes with several imaging processing packages out of the box. But the calculation/model you have to put in/program yourself. I'd be surprised if there is a ready made package available implementing the radiative transfer model.

    On the other hand (again checking Wikipedia) there are a lot of codes around modeling the radiative transfer, maybe it is better to use these codes and feed them with input data from MODIS in a format/language these codes expect. Then the question boils down to the question how do you extract the requested input data from the MODIS raw data. Again, Mathematica could be used to create data exchange files, but the other packages would do too.

    regards WG

  • Cindy Isabel Fuentes Gutiérrez added an answer in Diatoms:
    How do I get rid of bacterial contamination in my diatoms cultures?

    I tried using antibiotics (Amp, Tim) but these affects the diatoms, any recommendations? The use of antibiotics (Ampicillin and timentin) work well in Chlorella, Dunaliella and Tetraselmis but not in Phaeodactylum tricornutum and Chaetoceros calcitrans 

    Cindy Isabel Fuentes Gutiérrez · Universidad Autónoma de Sinaloa

    Kill them with fireeee!! xD

  • Cory J Knudson added an answer in Flow Cytometry:
    Does anybody have experience with heat stability of fluorophores commonly used in flow cytometry?

    Specifically, this is for an assay I'm using that requires staining of surface markers, followed by a 30min incubation at 37C. For example, I'm finding that I lose APC signal after incubation at 37C, but was wondering if anybody had experience with this happening with other fluorophores, such as the brilliant violet or common tandem dyes (PE-Cy7, APC-Cy7).


    Cory J Knudson · University of Iowa

    Hmm that's interesting.  What were you staining in APC?  In addition, for certain molecules, formalin fixation (especially prolonged fixation) can cleave the molecule so antibodies won't bind well (such as CD8a).  Definitely do not want to fix tandem dyes overnight also.  Otherwise your experience is a bit different from what I've seen.

    As mentioned before I work with lung cells, which I also have to do a digestion step for 30 minutes at 37 degrees.  In some experiments I have injected antibody into mice to label cells in vivo and then harvested the lungs for analysis.  I didn't have any issues detecting the fluorochromes FITC, PE, PerCPCy5.5, PE-Cy7, or APC after incubation for the 30 minute digest step.  However, I always targeted highly expressed molecules  and fixed the samples for only 10 minutes (with eBioscience Fix/Lyse solution).

    My only issues were the markers that I stained for rather than the fluorochromes.  Some molecules just tend to cycle, uptake the molecule, or change expression at 37 degrees.  Never tried using the brilliant violets, so not sure how they would work.

  • Moradkhani Hamid added an answer in Rainfall:
    How do you break daily rainfall duration to short duration rainfall data for rainfall intensity duration frequency curve

    we are trying to develop a rain fall duration curve for an area it doesn't exist

    Moradkhani Hamid · Portland State University

    This is a disaggregation problem which received lots of attention in the last decade. I suggest looking at the following two papers as a start:


    and also http://andrewsforest.oregonstate.edu/pubs/pdf/pub3636.pdf

    However, there are some more studies that consider the impact of climate change on developing the IDF as well.

    Hope this helps.

    Best wishes,

  • Geng Ouyang added an answer in Philosophy of Mathematics:
    Are mathematical statements ontological in a figurative/fictional sense, or in the literal sense of “what there is in the world”?

    Are mathematical entities fictional in the sense that they enjoy limited existential reference within the abstract stories told by mathematicians? Or in other words, unlike natural languages that can refer directly to objects in the world, like "There is a table here" -mathematics makes no such statements about actual objects. Some like Badiou ("Being and Event") claim mathematics is ontology.

    Geng Ouyang · MinNan Normal University

    Dear Mr. Daniel F M Strauss,

    Thank you very much for your insightful idea on “the world of knowledge” and your recommendation of the paper. It is really a good article.

    Yours, Geng

  • Joanne L. Tuohy added an answer in Monocytes:
    What is a good method for assessing peripheral monocyte migration in mice?

    I would like to evaluate peripheral monocyte chemotaxis in mice. I have used the Neuro Probe disposable ChemoTx plates previously for canine monocyte migration assessment, but the numbers of cells needed seem to be prohibitive for murine monocytes. Would anyone be willing to share a protocol for measuring chemotaxis in murine monocytes, including how much blood to collect? Any suggestions and thoughts will be much appreciated. Thanks.

    Joanne L. Tuohy · North Carolina State University

    Thank you Casey. I will look into it. 

  • Paul Rutland added an answer in IEF:
    Why current is not passing through the IEF strip?

    My 2D-sample is endotoxin protiein of bacillus sp. The sample is in Tris-HCl buffer pH 9.0. The sample was properly dialyzed. Rehydration was done with rehydration buffer and IPG buffer for 12 h. When i tried to run IEF with the abovesaid 11 cm strip, it shows 1 mA in GE ettan IPGphor machine. What could be the problem. Someone help

    Paul Rutland · University College London

    according to the manual

    At least two of three pressure pads under the safety lid should press gently
    against the strip holders to ensure electrical continuity between the strip hold
    er electrodes and the electrode areas on the platform.

    if there is no good contact the current will be low

    alternatively if the salt concentration of the sample is more than 10mM this will reduce the current so desalting the sample may work to give a good working current

  • Musa Peker added an answer in Microarray:
    What are different algorithms to analyse microarray data?

    I need to analyse microarray data ,so I need latest algorithms can any body help me to find ..

  • Guenter Grundmann added an answer in Light Microscopy:
    Can I perform reflected light microscopy with an inverted light microscope?

    I would like to perform reflected light microscopy to image the surface of a sample only, but only have access to a Zeiss Axiovert inverted light microscope. Is there any way to modify my scope to do this?

    Guenter Grundmann · Technische Universität München

    Dear Laura,

    I'm afraid it will not be possible to easily transform the Zeiss Axiovert in a reflected light microscope (incident light bright field microscope). A microscope that can illuminate the surface of a sample with a vertical light, requires a special so-called Smith-reflector (with a plane glass reflector and / or a prism reflector. This Smith reflector sits between the illumination lamp and the objective lens system.
    Based on the three attached images with the course of the beam path of three different types of inverse microscopes it can be stated that a simple modification of the microscope
    Type 1 - Zeiss Axiovert in a
    Type 2 - inverse microscope vertically reflected light (bright field) or in a
    Type 3 - inverse microscope Dispersed light ring illumination (dark field)
    will not be possible.

    Best regards,


  • Edwin A. Locke added an answer in Causality:
    Is a concept of causality required in science?

    John D. Norton characterized "Causation as Folk Science",

    (see http://quod.lib.umich.edu/p/phimp/3521354.0003.004/1).

    Would you say that causality is a well-defined concept that is

    essentially required in science?

    Edwin A. Locke · University of Maryland, College Park

    so let's see: causality operates in everyday life but not in science which tries to explain what happens in everyday life--such as bacteria causes disease, acceleration makes it possible for airplanes to fly,  pressure causes gas leaks, heat causes molecules to move faster and thereby boil water, and so on--so science is in some other (Platonic?) dimension--sorry but this is too bizarre- Arkady you seem to have another whole agenda: personal hostility towards people with stature--now I agree that a lot of crap goes on in science and that govt control of research grants has very bad consequences but this does not mean that nothing gets discovered-- probably the healthiest field today is biology--things are being discovered-

  • Kenneth M Towe added an answer in Environmental Science:
    Copyright permissions.

    Reprinted (adapted) with permission from (Moore, M. E., & McFarland, A. R. (1993). Performance modeling of single-inlet aerosol sampling cyclones. Environmental science & technology, 27(9), 1842-1848.). Copyright (1993) American Chemical Society.

  • Yang ni added an answer in UV/VIS/NIR Spectroscopy:
    Can anyone recommend off-the-shelf cameras for NIR, SWIR, LWIR and TIR infrared bands?
    Our project is focused on FPGA acceleration of primitive convolutions and transforms associated with multi-spectral sensor fusion and while visible CCDs are plentiful and quite affordable, finding good and well priced IR detectors with common interfaces like analog NTSC, USB 2.0 digital and GPIO digital interfaces are a bit harder to find - we've been looking at solutions like Xenics (http://www.xenics.com/en/index.asp), JAI (http://www.jai.com/en/), and Tetracam (http://www.tetracam.com/Products1.htm), but curious what others have used and like and why.
    Yang ni · New Imaging Technologies

    Please take a look at our website: www.new-imaging-technologies.com. We provide Widy SWIR InGaAs cameras with USB, CL and CCIR outputs. 

    Thanks !

  • Hammad Cheema added an answer in Perovskite Solar Cells:
    What is causing the low fill factor of MAPbI3-spiro based solar cell, when current is around 16 mA/cm2 and Voc is 0.9V?

    I had made some Perovskite solar cells, current up to 16mA/cm2 and Voc of 0.9V was achieved but FF was around 26 which was killing the efficiency, and in different cells that is consistent? can you suggest the possible cause.

    Hammad Cheema · North Carolina State University

    After doing XRD, it is quite clear that the method i was using was not reacting all of the PbI2, which might be the reason for low FF, looking forward to make cells with modified method.....

  • Réka Szőke added an answer in Radioactivity:
    Do you guys have some information about distribution coefficients of Ni and Cs?

    I'm searching some info. about Kd of radioactive Ni, and Cs on sedimentary rocks.

    If you have info, could you let me know that?

    Réka Szőke · Institute for Energy Technology

    You may find Kd of Ni (from representative soil samples from Brazil's eastern Amazon region) in the following article: http://www.ncbi.nlm.nih.gov/pubmed/23625050

    Distribution coefficients of potentially toxic elements in soils from the eastern Amazon by
    Anderson Martins de Souza Braz et al.

  • Hammad Cheema added an answer in Perovskites:
    Does anyone have an idea on the purpose of heating the perovskite precursor solution at 70 C right before spincoating?

    What is the purpose of heating the perovskite precursor solution (PbCl2 and MAI) at 70 C right before spincoating? Is there any other purpose (ex activation?) for heating other than fully dissolving the precursor to DMF? 

    Hammad Cheema · North Carolina State University

    This is tricky, PbI2 solution should look clear yellow before spin coating. I used to dissolve PbI2 in DMF at 70C overnight and still see it hazy. Use of syringe filter did helped me to get the clear yellow solution. With my experience, other than dissolving warming the PbI2 solution to 65C before spin coating gives more even results. 

  • William Mcdaniel added an answer in rTMS:
    Is there some rTMS protocol for depression with suicidal risk?

    The standard protocols for depression require several applications to obtain favorable results. Should people with suicidal risk is necessary to obtain positive effects in less time. Maybe one of you has a paper where they have experimented with this.

    William Mcdaniel · Hampton VA Medical Center

    There is no "standard" protocol, but Rohan's group at Harvard are working on this, and have a new device and some data.  Start with

    Rohan M, Parow A, Stoll AL, Demopulos C, Friedman S, Dager S, Hennen J, Cohen BM, Renshaw PF. Low-field magnetic stimulation in bipolar depression using a MRI-based stimulator. Am J Psychiatry 2004;161(1):93

  • Helmut Ziegfeld Baumert added an answer in Fluid Dynamics:
    Please. help! Is there any method to solve this nonlinear PDE using similarity?

    I stumbled upon equation j and l in my research.

    I found some books related to fluid dynamics, it says solution to j is the formula k

    (it didn't give the procedure, just solution)

    as you can see j and l looks similar. and similar boundary condition and mass balance.

    Assuming that solution to j is k, Is there any method to solve l and get the formula of h2?

    I tried to solve j analytically by using separation of variables, but it gives second order nonlinear ODE; and I made Wolfram Alpha solve it. but still it didn't respond. 

    so I decided to circumvent reaching the solution by using the similarity

    Helmut Ziegfeld Baumert · IAMARIS - Research and Consulting, Ludwigslust, Germany

    @Kim: I make a U turn as  I now realized that you have full cylinder symmetry and as an initial condition something like a delta/dirac function? Besides the wrong written parabolic term in the second of your PDEs the initial condition needs to be specified. The allegedly analytical solution (k) exhibits a singularity at t -> 0. What is still irritating is the solution-dependent diffusivities of h1 and h2. They are not identical so that turbulent mixing may be excluded. Yes, this is a hard task and will take time to solve it. Besides, I assume that h2 exhibits a similar structure in terms of separation of the variables. There shouldn't be too much difference. So from a practical point of view I fully agree with Kare Olaussen. Don't invest too much into Lie groups etc.. But please verify that in the second PDE the term dh1/dr should be  replaced by dh2/dr.

  • Mohamed El Naschie added an answer in Pure Mathematics:
    The concept of variation of the mass versus the velocity (m =m0/sqrt(1-(V^2/c^2)) is it a pure mathematical concept? or is it a physical reality?

    theory of restreint relativity

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

    dear all- i agree with all of you. each of you stressed a certain poit and all in the right direction

  • Victor R Kebande asked a question in Cloud:
    Can BYOD + Cloud be the NGN effective computing?

    Taking into account the security concerns, how effective can the two work?

  • Laurence Stuart Hall added an answer in SYBR Green:
    Using SYBR Green I master mix with Taqman probes

    Can someone explain in some what simple terms why we can't use SYBR Green I master mix with Taqman probes?

    Laurence Stuart Hall · University of Leicester

    Hi there. Sybr green generally speaking is something that is used as a cheaper alternative to more specific Taq man probes. As already mentioned sybr green binds to double stranded DNA and as such will identify all amplicons in a real time PCR reaction both specific and non specific. This is why qPCR reactions terminate with a melt cycle designed to identify all amplicons products including specific products non specific products and with particular regard to the latter primer dimers. In this sense it is analogous to identifying all amplicons on an agarose gel following conventional PCR with ethidium bromide and sybr dyes. Moreover just as it is necessary to optimise conventional PCR by paying particular attention to the annealing temp of the reaction and screening primers for inter and intra binding with the intention of generating just one specific product devoid of primer dimers so attention should like wise be paid to the set up of qPCR reactions using sybr green. In deed before commencing qPCR using sybr green I always personally make sure I can only see 1 specific product on an agarose gel with a particular pair of primers and design 2 or 3 pairs of primers to my target region and only use the 1 set in sybr green qPCR that yield the most specific and efficient results by agarose gel electrophoresis plus sybr staining. Target and standardised reaction specific Taq man probes circumvent these problems and dispense with the need for the same amount of optimisation

  • Alexssandro Geferson Becker added an answer in Antioxidant Enzymes:
    How can I calculate an oxidative stress index?

    How to calculate an oxidative stress index based on data of antioxidant enzymes (SOD, CAT, GST, GPx ...) and oxidative damage (LPO...)?

    Alexssandro Geferson Becker · Universidade do Algarve

    Dear Thiago Rocha,

    I would like to suggest the following index: LPO/CAT+GPx ratio, as reported by Ruas et al. (2008) and Salbego et al. (2014).

    Ruas, C.B.G., C.S. Carvalho, H.S.S. de Araújo, E.L.G. Espíndola & M.N. Fernandes. 2008. Oxidative stress biomarkers of exposure in the blood of cichlid species from a metal contaminated river. Ecotoxicology and Environment Safety, 71:86-93.

    Best regards,

  • Aditya Bansal added an answer in Cardiac Surgery:
    How often is poststernotomy mediastinitis caused by Coagulase Negative Staphylococci (CoNS) in your unit? More often than S. aureus?
    Why do you think this is the case?
    Any special precautions?
    Aditya Bansal · Ochsner

    We have not noticed that. My question would be is Id service following this and trying to find why you all are noticing an increasing rate in your unit. Maybe they can shed some light and do a route cause analysis.

  • Mohamed El Naschie added an answer in Journal Impact Factor:
    What is the credibility Scientific Journal Impact factor which is calculated by InnoSpace (http://www.sjifactor.inno-space.net)?

    What is the credibility Scientific Journal Impact factor which is calculated by InnoSpace (http://www.sjifactor.inno-space.net)?

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

     dear mokhtar--  i take all impact factors and all h-index and the like with more than a grain of salt , Elsevier Scopus   is made to promote Elsevier . all are tampered with

  • Kulothungan Ganapathy added an answer in Aromatase:
    Where can i buy Aromatase enzyme (contorl ) for Western blot?

    Suggest places to buy Antibodies as well

    Kulothungan Ganapathy · University of Cincinnati

    Thank You Liz  for your kind reply

    Pls do provide me the  SEQUENCE/ PRIMERS.

     I did find antibodies from abcam. Now i am looking for a pure or crude Aromatase enzyme to use as control in western blot. Do you know a source for buying or getting Aromatase enzyme ?



  • Marianne Vidler added an answer in NVivo:
    Nvivo10 how do I know what are the nodes I have coded for a certain paragraph of the source?

    I have a long source, I need to know what nodes I have coded for a certain paragraph in this file! how can I do this?

    Marianne Vidler · University of British Columbia - Vancouver

    You can also do a coding query for the source of interest and any or all nodes of interest.  

    Another approach is to use the graphing tool this will allow you to make graphical representations of the nodes/coding of particular sources.  

    Once coding stripes are turned on this can be printed as a PDF.  This is an excellent way to share work with other researchers in the team. 

    There are many strategies to look at this it all really depends on what you must want to represent.  It is, however, difficult to represent the coding of just one paragraph rather than the whole source. 

  • Erica Squires asked a question in EIA:
    Is SPE required to prep urine samples for EIA? How to choose the right column?

    I see most people running urinary steroid hormone and oxytocin assays are publishing that SPE is required as sample prep, but I have been unable to replicate results reliably. I can use a commercially available EIA kit that does not require SPE prior to running, but I'm looking for good resources on how to know what sample prep is appropriate for your sample matrix and testing method as well as how to choose the correct SPE column. There are multiple types in the literature that are used. For example, oxytocin extractions interchangeably report using Phenomenex StrataX, Waters Oasis HLB, and Sep Pak C18,

  • Olusola Ogunnubi asked a question in Soft Power:
    Can our understanding of regional hegemony be improved by the inclusion of soft power?

    In the context of African regional powers

  • B. J. Adekoya asked a question in Eclipse:
    Is there any time difference in minimum decrease of TEC and foF2, If yes, what could be responsible for it?

    The delay time of the minimum decrease of TEC after the maximum magnitude of eclipse is smaller compare to the foF2. What could be responsible?

  • Frank Lucatelli added an answer in Electromagnetic Fields:
    Are electromagnetic fields made up of virtual photons? Or are they merely a mathematical bookkeeping device for QED?

    QED rests on the idea that charged particles (e.g., electrons and positrons) interact by emitting and absorbing photons, the particles that transmit electromagnetic forces. These photons are “virtual”; that is, they cannot be seen or detected in any way because their existence violates the conservation of energy and momentum. Is there a way to explain virtual photon without using the uncertainly principle?

    Frank Lucatelli · HEAR, Inc.


    I want to respond to your comment about forces and also to clarify what I meant by the issues of scale.

    Starting with the issues of scale: The uncertainty principle is not an exclusive property of QM. Speed and position may not be defined simultaneously. The issue of scale creates a similar related problem to the uncertainty principle, which I will call an ambiguity problem. For example watching an airplane fly one could say that it can fly because it has wings. However, the issue is aerodynamic lift, which is not understandable at the scale of the airplane, it must be analyzed at the scale of the wing where differential pressures due to air flow create unbalanced forces that lift the plane. At the level of particle physics, Tom and I believe that there are similar ambiguities that enter the discussion because we are not yet clear about the differential scales that are involved in the construction of matter at the particle and sub-particle scales. That is a main point of our paper, in that we attempted to clarify those scales.

    We felt that it was important to clarify the scales of activity that lead to the production of matter. We purposely avoided moving into the mathematical description of forces for that purpose, as well as the fact that we do not have the background to attack the mathematical relation of forces reliably. For that, we were hoping that others may guide us in establishing those mathematical relations.

    So in response to your comment, I would ask you if you have suggestions that we may follow that could produce results that you desire? We would much rather focus upon an answer to your question that is focused upon a data point that would be useful, rather than those questions that we find interesting.