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  • Lale Evsen added an answer in Neurogenesis:
    Doing a double neurognesis staining. besides Brdu, which one can be the alternative neurogenesis biomarker, EdU, CiDU, or IDU?


    I am interested in studying neurogenesis in an epileptic rat in different time point. I am planning to do a double staining with two different neurogenesis biomarker. 

    I know that Brdu is a golden standard. But is there any alternatives can have the similar sensitivity as BrdU

  • Mahfuz Judeh added an answer in Business Strategy:
    Is the gap between 'projects' and 'strategy' real and how BSC tool can contribute to eliminate it?

    According to Morris and Jamieson (2004), ‘there is little literature on how business strategy is translated in project terms and this itself comprises a not-well researched or written about topic’.

    Mahfuz Judeh · Applied Science Private University

    There are three stages for strategy:

    Stage one: Strategy formulation.

    Stage two: Strategy implementation.

    Stage three: St

  • How can one determine the instrumental resolution of a X-ray diffractometer better?

    I observe thinner peaks from a diffractogram of aluminum than those observed from a LaB6 standard powder.

    Pieter Bertier · RWTH Aachen University

    Dear Henry,

    I have not tried this myself, but there is an example given in the manual of BGMN (see: http://www.bgmn.de/tubetails.html), that states that the SRM LaB6 powder has some size and strain broadening, and I have seen several other papers that confirm that (e.g. http://www.geocities.ws/aang_au/JAC_35_155.pdf). So maybe your sample just has less size/strain broadening?


  • Bhushan Bhoja Poojary asked a question in Projection:
    What is shape of our universe?

    Its been told that we are all projection of holographic plate , can anybody let me know what is shape of our universe?

  • Ahsan Jawad asked a question in Alumina:
    Is there any information about sol gel alumina manufacturing

    i am working on a new power transmission conductors made of Al and aluminum composite core (aluminum matrix with alumina )

  • Are PISA scores a good test for national education?

    The Programme for International Student Assessment (PISA) is a challenge to test education systems by testing the skills and knowledge of 15-year-old students.

    Do you think that this method is a good test?

    In the link you can reed the PISA 2012 results.

    Οικονόμου Στέφανος · Hellenic Open University

    It is an interesting opinion the negative impact on students' phycology, but i believe that students (at least in Greece) do not care about Pisa's results. A similar question could be the negative impact on peoples. Citizens of a country that always be on the bottom of pisa's scale could have negative phycology about their education policy or their personal skills.

  • Szymon Strnad added an answer in Candida:
    Have you tried any media other than YPD media for stocking Candida spp.?
    If yes, please could you share the information_
    Szymon Strnad · University of Agriculture in Krakow

    I wish you good luck and all the best, Dr. Godfred! Hope you are going to get satisfactory result!

  • Kunal Garg asked a question in Analytical Instruments:
    How to estimate the mineralogical composition (C3S, C2S etc.) of cement?

    How to estimate the mineralogical composition (C3S, C2S, C3A, C4AF etc.) of cement? Is there any analytical instrument or we can estimate it from oxide composition?


  • Marwan M. Obeidat added an answer in Skype:
    Is telecommunication systems technology a bliss/heaven/extravagance or a condemnation?

    With the advent of hi-tech telecommunication systems including cell phones, the Internet, Skype, Viber, Facebook, Twitter, WhatsApp, etc., our world has become a global village. Yet, it has also become more sophisticated and more demanding than ever before! Moreover, common privacy has almost diminished in much the same way as our leisure has! Things have become faster for sure, but have not we, in turn, become somewhat like social machines, given all the extravagance technology has given us?

    Marwan M. Obeidat · Hashemite University

    My dear friend, Nelson, whether a blessing or a curse, I think we have to live with these technological instruments, no matter how good or bad they can be! Our options, if any, are VERY limited!

  • I am writing a book on molecular biology and I need an Editor?

    Dear All

    I am writing a book on molecular biology and this is about to complete. it contains 9 chapters covering various aspects of fundamental process of molecular biology. i need an editor for this. How can I assign or find editor for my book to publish. Need help as I am novice to this field. Looking forward for responses.... 

    Farzan Ghane Golmohamadi · Agricultural Biotechnology Research Institute of Iran

    I think, you should  find an appropriate publisher, first of all. They will do all thing by themselves if they find the book worthwhile

  • Ebru Tekin added an answer in Contamination:
    Fungal genomic DNA isolation issue? I am seeing low MW bands of contanination in my gels... ANY IDEA?


    My DNA isolation protocol seems to be working ok but I am seeing some low MW bands around 75-300 bps. Attached you will see my most recent gel. Gels (1% agarose) run for 30 minutes @ 130mV. Any idea what the low bands could be? I am looking for clean high MW DNA for sequencing this organism. 

    To give more background on my gDNA isolation protocol, I am running a phenol:chloroform extraction with both a RNase A and proteinase K digest. I am able to reproduce these results but everytime I isolate DNA I am seeing these smaller bands present in my DNA samples. I am working with a fungal cell whose cell wall is very difficult to disrupt. I am using a freeze-dry approach and mashing up cells into a fine powder. In my final steps, I am using a isopropanol and then an ethanol precipitation of DNA.

    When running nano-drop analysis, I am seeing a  OD (260/280) of around                  1.98-2.0. so I can assume there is some sort of contaminant. I know I should be seeing a reading closer to ~ 1.8. I have been told everything from "I have RNA contamination, to even having protein contamination." I am not sure what it is, but does anyone have any easy ways to clean these contaminants out?   

    Thanks for input!

    Dan Roettger

    Ebru Tekin · Ege University

    Hi, If you think that the problem is the RNA contamination you can already check this by using RNase to your final DNA solution and check by electrophoresis. But I think that the main problem is the low yield of gDNA which may have occured by the low starting material, the ineffective way of the lysis of cell wall by freeze drying also the freeze drying process may break the gDNA. If you have possibility use fungal cell wall lysis enzyme instead of freeze drying. Do not vortex if it is not necessary that will also break the gDNA. You may increase the amount of the fungus and you may use genomic DNA extraction kits as well.

    Good luck

  • What method(s) can one adopt to obtain appropriate aquifer for potable water in coastal communities in Niger Delta Nigeria?

    Borehole water is the only source of reliable potable water to this environment. However, sampling of the water quality has shown contamination. Perhaps as a result of soil porosity enhancing salt water intrusion, inter aquifer exchange, and sometimes iron loadings from upper region being deposited by river flows. Presently, there is no engineered landfill, and so all the municipal solid wastes are dumped in open pits. This also enhances leachates transfer to ground water levels. With all these complexities it becomes difficult to choose optimum aquifer for potable water extraction. Please advise the method to adopt.

  • Kunal Garg asked a question in DTA:
    What is the role of Thermogravimetric analysis in concrete?

    Please anyone can tell me what is the role of TGA/DTA in the analysis of concrete? What it depicts? Why we do TGA analysis of concrete?


  • Woonghee Lee added an answer in Zinc Sulfate:
    Is anyone familiar with Zinc addition to E. coli growth medium?

    I am facing serious trouble with expression of a zinc-binding protein in M9 labeled media. The protein is a GST-fusion protein and is said to bind to zinc ions. It expresses extremely well in LB medium (several tens of miligrams per liter of culture), but does not express at all in M9 medium (and also in CIL medium "Spectra 9"). Of course everyone I ask tells me that this is strange and something is seriously wrong.

    Indeed the cells grow well in M9, so I asume this is purely an expression problem. When I run the E. coli cell extract on a gel, I see a sharp band for where GST would migrate and only a faint band where I would expect my target protein.

    Therefore, I am currently assuming that transcription is correctly initiated by IPTG, however the protein does not fold correctly and is thus degraded in the bacterial cell and only the soluble GST tag remains. Misfolding could occur if the cells cannot access zinc (which would be available in LB in traces, but not in M9 if my zinc administration is wrong). Therefore, I would like to ask for the correct method of addition of zinc to a culture of M9 minimal media.

    I tried the following variety of conditions without success for expression in M9:

    E. coli: BL21(de3) / C41(de3) / C43(de3)
    IPTG 0.1 - 1 mM
    Temperature: 16 - 22 C
    OD600 at induction: 0.5-0.8

    Zinc administration: stock solution (50 mM zinc sulfate) is added to the culture flask 30 minutes prior to induction with IPTG (final concentration of zinc sulfate: 0.2 mM).

    I also tried Marley's method (grow the cells in LB first and exchange the medium to M9) which also resulted in no protein yield at all.

    Desperately hoping for a bit of advice,



    Woonghee Lee · University of Wisconsin, Madison


    Here the answer.

    1. No, the Studier metal mix (that Ronnie from CESG uses for CESG targets too) has no EDTA : http://www.helmholtz-muenchen.de/fileadmin/PEPF/PDF/Studier_05.pdf

    2. Yes, the zinc does form a insoluble precipitate when mixed with the phosphate. There is no way around this, even using ZnSO4 instead you get a faint white precipitate or cloudiness in the growth media. Some groups add the excess Zinc just before induction with IPTG.

  • Ahsan Jawad added an answer in Surfaces:
    How do you estimate the diameter of a surface dent left by a ball pressed against a flat surface?

    Consider a small ball made of very hard material and pressed against a flat surface made of a relatively soft material. When plastic deformation occurs, the ball leaves a circular dent on the flat surface. Given the magnitude of the contact force, is there an analytical model to estimate the dent diameter?

    If not, which software is recommended for this type of simulation?

    Ahsan Jawad · Ministry of Science and Technology

    i think if you have some informations about Rockwell Hardness test method method you will find what you are looking for


  • Eric Crandall added an answer in DnaSP:
    Does anyone know of a 'easy to understand' guideline (step by step) for calculating and interpreting Fst, AMOVA etc. in populations genetics?

    We have mtDNA sequences (cyt b 600 bp) of fish and want to determine the 'connectivity' between populations using Arlequin, Network, DnaSP, Mega software packages. Also, need to identify unique haplotypes within populations. However, we are in need of some instructions to ensure accuracy. Many thanx!!

    Eric Crandall · University of California, Santa Cruz


    Shane Lavery has an excellent introduction to Fst (linked below) that I use for teaching, and Chris Bird has an excellent review of the subject (also linked) with Peter Smouse among others, who was an author on the original AMOVA paper. As Amal says you could use these to get better acquainted with the subject.

    My own research and that of others has left me with the opinion that Fst (of any flavor- Phist, Rst, Gst) is not so good for connectivity analysis, especially in marine species, so use and interpret with care. Robin Waples had an influential article about this (below). It is often depressed by high heterozygosity (nucleotide diversity in the case of mtDNA) to where it is not significantly different from zero and thus without information to test hypotheses. However, for much the same reason (high genetic variability), a coalescent analysis such as Migrate can get more information for you than it could for many terrestrial species. See my linked article below for an example.

  • Margareth Borella added an answer in Supply Chain:
    Someone knows scales to evaluate the sustainability through supply chain?

    I am researching the sustainability under TBL approach. I intend to identify levels of sustainability in the focal company and its members (suppliers and clients).

    Margareth Borella · Universidade de Caxias do Sul (UCS)

    Thank you Iuri. 

  • Ricardo Azpiroz asked a question in LSC:
    Beckmann LSC

    I stupidly turned off our old Beckmann LSC 6500 and now the display is showing gibberish. The unit won't respond to commands from the keyboard. Any advice?


  • Is there any method to differentiate between two phenotypes of Photorhabdus through C source?

    We have two different phenotypes of Photorhbdus bacteria. So we are going to characterize and differentiate between them. So, what type of media can be used to characterize them?

    Hi khan

    Indeed i can't say if the attached paper and link are good/bad because the subject does not fit with my interest field, please check them.
    With my best regards

  • Does anybody know if there are papers about islands in complex networks?

    Islands are subnetworks in complex networks

  • Is there a reliable way of electrophoretic deposition of nanoparticles on the surface of one of two parallel band electrodes?

    I'm trying to electrophoretically deposit nanoparticles on one of two band electrodes. After applying DC voltage, my negatively charged nanoparticles deposit only on the edge of the anode and I want them to deposit on the whole surface of the electrode. Is there a way to do that?

    F. Caballero-Briones · National Polytechnic Institute-CICATA Altamira

    Yes, cover the edges of the electrode with an insulating coating, epoxy, varnish for example to avoid the higher overpotential you have in the edges.

  • Ângela Giovana Batista asked a question in Akt:
    How is the better way to normalize phosphorylated proteins analyzed by Western blot? With structural proteins or with their total protein pair?

    I am working with phosphorylated proteins, using the western blotting technique. I have seen in the literature both phosphorylated proteins normalized with structural proteins, such as actin, or tubulin and with their total pair (phospho-AKT/AKT/ actin), and only normalized with its total pair, such as phospho-AKT/AKT. What is the better way to do this?

    Thank you for your atention.

  • Are there any personality assessment models other than MyersBriggs which have proved accurate or at least close to?

    We are trying to assess employees personalities to understand what kind of personalities work well with other.

    Donna Marcelle · Sofia University

    Lumina Learning offers quite accurate personality assessments based in Jungian Psychology and the company is a joy to work with. Stewart Desson is the researcher and founder based in the U.K. at www.luminalearning.com.

  • May Hijazi added an answer in Nuclear Proteins:
    How can I optimize the experiment to be able to see the nuclear protein fused with YFP in the nucleus?

    I am over-expressing a protein of interest (implicated in DNA repair) in fusion with yfp in Nicotiana Benthamiana leaves. The proteomics data showed that the protein is cytoplasmic as well as chromatin assotiated. The microscopic studies done at the same time showed high cytoplasmic expression for the protein but couldn't detect the protein in the nucleus. Under YFP filter, I can see fluorescence around the nucleus and faint color inside. I used as a control for nuclear localisation mcherry "expressed by the same construct" which showed very bright fluorescence. I am just wondering if there is a technical issue that hinder the bright nuclear fluorescene (could be the high cytoplasmic fluorescence!) and how can I optimize the experiment to be able to see the nuclear fluorescence. Thank you.

    May Hijazi · Agriculture and Agri-Food Canada

    Thank you so much for your answers

  • How reliable is NeuN for labeling neurons? Is it possible it labels other cells too?
    I am not sure if the possibility was ever exhausted that it labels other cells like glia.
  • Maria Gokieli added an answer in UV Radiation:
    Who knows the properties of fractional power of negative Laplace operator?

    For example, (-\triangle)^{\alpha}(uv)=?        Here, 1/2<\alpha<1.

    Maria Gokieli · University of Warsaw

    The book of Dan Henry 'Geometric Theory of Semilinear Parabolic Equations' is a good reference on the subject. He treats 'sectorial' operators in general, but minus laplacian is one of these, and his main example. The book is typeset in an old manner, but really worth reading. Especially that your problem is in Chapter I - Preliminaries. 

  • How to assign names to microbial species identified from shotgun metagenomic assembly?

    • From metagenomic analysis nearly complete microbial genomes can be identified. Some of these microbes seem to be unculturable, and are impossible to manage with “standard” microbiological methods. As expected, considering average similarity level with genomes deposited in database, some of the species identified using metagenomics can be considered as new strains of known species, some others seem to be new species but can be referred to known genera, others are impossible to refer to any previously sequenced microbial species. Do you know if there are some general rules to assign names to species belonging to these three different categories? Is the use of “Candidatus” term correct for well characterized but as yet uncultured organisms? How can we use the term “Unclassified”? Is this term correct for new species clearly associated to a certain genus (i.e. Parabacteroides unclassified)?

    Taras Y Nechitaylo · Max Planck Institute for Chemical Ecology

    You can find the answer to your question in this paper:

    Murray RG, Stackebrandt E. (1995) Taxonomic note: implementation of the provisional status Candidatus for incompletely described procaryotes. Int J Syst Bacteriol. 45:186-7.


  • Chengjun Zhang asked a question in Hydrolysis:
    Hydrolysis constants of Cr (VI) and Cr (III)

    Could anyone know the hydrolysis constant of Cr (VI) and Cr (III)? Thanks!

  • Is there any way to calculate the amount/percentage of the CH from XRD spectra for a hydrated cement powder?

    I have a powder sample obtained from a hydrated cement and I want to calculate the amount of the CH compound from the XRD pattern of this powder. Is that possible or not?

    Any help would be appreciated!

    Mahmoud Khashaa Mohammed Al-Ani · University of Anbar

    Deep thanks to all the participants. Qiang Yuan, Monday Uchenna Okoronkwo and Dominique Ectors accept my regards.