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  • Santhosh Gatreddi added an answer in Recombinant Protein Expression:
    Why e.coli produce both fusion protein and fusion protein+recombinant protein?

    When I produce recombinant protein by expression vector such as pMAL or pET43

    Santhosh Gatreddi

    Due to degradation of your protein while expression.

    I also faced same problem with GST.

  • Nuttapon Khongdee asked a question in Nutrients:
    What is the changes mechanism of nutrients in soil such as C, N, P, K, Ca and Mg ? Do you have any publication that explain about this?

    I need a reference.   

  • Oadi Matny added an answer in Cell Wall:
    What is the best method to break the cell walls of fungi?

    Hi. i want to know what way is the best to break the cell wall without destruction a secondary metabolite? can everyone help me?

    i want break it to measure the secondary metabolite concentration using uv-vis spectrophotometer.

    Oadi Matny

    Hi, there are many methods for that, one of them you can use ultrasonic to break cell wall, or by freezing the fungal mycelia on liquid nitrogen and grind with mortar 

  • Alvin Vista added an answer in Rasch:
    School climate scale: could a Rasch 'speaking' psychometrician please advise me?

    I read the attached presentation by Bergh and Fokuoka with interest - I am designing a study using the School climate measure - and wondered what is meant by "The precision of measurement could be improved by inclusion of additional items of appropriate severity" (slide 50). I think it means the construct isn't well enough covered but does it need easier or more difficult items to endorse? Thank you.

  • Aneesh P. A asked a question in Bromination:
    Please suggest a method for the quantitative determination of added ammonia in fish/meat samples?

    In current method we are using Bromine, looking for another harmless method preferably using kit.

  • Hyunggyu Lim added an answer in Arctic Regions:
    How can I draw the regular arrows for wind vector in arctic region using the Grads or other graphic tools?


    I tried to draw the Arctic arrows(set mproj nps) of u & v winds using the grads.

    Data is NCEP/NCAR R1 regular grid 144x73, but it looks complicated.

    Because, higher latitude of grid is continuously smaller and arrow spacing will be smaller from low to high latitude I think. Skip function was not helpful in grads.

    If someone who know how can we draw Arctic arrows to be regular, please help me for this problem.

    + 1 more attachment

    Hyunggyu Lim

    Dear Enda William O'Brien

    I'm very happy and thank you for your helpful kind comments.

    I perfectly solve my problem from your answer.

    Thank you very much!

  • Wirat Lerdprom added an answer in X-Rays:
    Does anyone know or have any papers about ' x-rays discoloring in glass?

    Any suggestions on 'x-rays discoloring in glass' will be appreciated. 

    Wirat Lerdprom

    Dear Prof Shelby

    Thank for your contribution, how can I forget your work on glass since I do have your introduction of glass book when I was at Alfred.

    Once again, thank you for your supports.



  • Nur Syafiqah Hashim added an answer in Microbubbles:
    What are the two microbubbles behavior compared to one microbubble?

    When the bubbles in one and two interaction. what will happen to the bubbles behaviour. Then in two microbuubles, what will happen.

    Nur Syafiqah Hashim

    this is helpfull. thank you for your opinion.

  • Konstantin J Sylus asked a question in ArcGIS:
    What is the best method of mapping in Arcgis?

    I am doing salinity mapping in coastal aquifer. I want to know which is the best method used for mapping...

  • Catalina Crisan-Mitra added an answer in Corporate Social Responsibility:
    Which factors/indicators are relevant to evaluate a company’s CSR performance?

    Please recommend me some perspectives that should not be missed when evaluating CSR performance.

    Catalina Crisan-Mitra

    Thank you for recommendations!

     For Aldo

    I am making a survey on large Companies that operate on Romanian market to see CSR particularities. It would be useful to see what your KPI recommendations are.

  • Justyna Pilarska added an answer in Plagiarism:
    How much % of plagiarism is allowed for the acceptance of research paper?

    advance thanks for ur answers.



    Justyna Pilarska

    You welcome! :-)

  • Kannan Sugumar added an answer in EPR:
    Is the Enhanced Permeability and Retention (EPR) effect applicable for 25 kD macromolecules?

    How can I justify the EPR effect for polymeric anticancer drugs with molecular weight 25kD or lesss.... There are more reports for EPR effect of macromolecules with molecular weight more than 40kD.... Is it so?

    Kannan Sugumar

    Thanks for your kind reply....

  • Abdul Ghafoor added an answer in Conservation Agriculture:
    How can I maintain land races?

    Land races of crop are treasure of useful genes but are low in yield. So farmers avoid their cultivation and they are disappearing. How can they be maintained.

    Abdul Ghafoor

    Dr. C.J. Stigter has proposed good way to conserve land races. I think there is strong need to establish gene pools for which planners and policy makers need to be taken on board. The govt should take steps ahead with the involvement of professionals. Such gene pools could prove useful as well for new variety development programs to address the climate changes etc

  • S. Sarvade added an answer in Social and Cultural Anthropology:
    I did my PhD on NGOs and watershed management:peoples participation and impact on the farmers of prakasam district. A.P. India. I want to know any res...
    I want to know any research works in anthropology related to NGOs in India or abroad.
    S. Sarvade

    The study was carried out for only prakasam district, it may be related to NGOs in the India, but it depends on sociological problems of the peoples.

  • Gert Nolze added an answer in Metals:
    Any advice on EBSD - pattern quality?

    What are the possible reasons of unvisibility of EBSD pattern? I have measured EBSD on substrate and subsequently on deposited layer (by PVD). There vere only some areas where the Kikuchi lines were visible (and indexed). The measurements were performed on as-deposited layer (with no treatment). It is not clear for me the reason why somewhere the kikuchi lines are quite clearly visible and on the other place they cannot be detected at all. I suppose that the layer should not be amorphous. Moreover the indexed areas have preffered orientation. I know that there are some factors influencing the pattern quality (e.g. dislocation density). Is it possible that the bcc metal has so much better conditions for diffraction in certain orientation? Or is there another possible explanation of such phenomenon?

    Gert Nolze

    XRD makes no sense since your grains are much too big. I guess that the pattern quality map displays the big grains from the substrate but also from the layer, right? If the grains of the layer (which should be actually displayed by BC) are clearly smaller, then I would agree with some of the comments made above. 

    Again, if you are sure that there is a layer on the top (by EDS) then it does not mean that EBSD reflects the same information (since only from 20nm) whereas your EDS gives you the information from a few microns, i.e. 100 times bigger depth. Oxidation might be a reason since O attacks crystals orientations differently- This would explain, why do you see several grains in an acceptable quality, and starting from the boundary you do not see other grains. It also seems to be very unlikely (not impossible) that exactly from there a nanocrystalline microstructure appears. 

    Also the message that crystal of 300-400nm size are the lower limit of EBSD measurements are far away from beeing true. Of course it depends on the material, but  Ti is not Si, and even there the lower limit is smaller. Otherwise you couldn't resolve martensitic transformation. For illustration I simply add a snapshot of a Ti-map (Ti-AL) with "fcc" /red), hcp (blue) and bcc (yellow) and TiB (green) and the respective IPF-X map scanned with 80nm at 20kV (sorry for the inaccurate snapshots, but both maps shows the same microstructure). You can clearly see grains smaller that 300-400 nm. We did not used ion polishing, simple standard metallographic preparation with silica as surface finishing. And...these are the original data, i.e. no data cleaning has been applied.

    Also please consider, that the question is not, why the EBSD system does not index. This is another question! The shown BC map in one of Jaroslavs contribution shows that there are no bands visible, i.e. the diffraction signal is missing so that no software can index.

    Also consider, that even highly deformed materials like martensite can be still indexed as long as bands are visible. Hough transform is perhaps not the best way for high accurate orientation determination (required for GND analysis) but for orientation determination it is sufficient since a quite big range of acceptance (deviations) are implemented in the software which still enables to index. There it might happen that a software gets problems if the patterns are too good since the clear seperation of bands becomes more and more difficult (too many peaks in Hough transform).

    + 1 more attachment

  • David Dunaetz added an answer in Thirst:
    Do you think that low status categorisation consequences are equivalent when we talk about ethnics groups and gender groups?

    Personally I think that they are qualitative differences. For me, one example of this difference is the generation (first, second, thirst, etc.) of the immigrants. I think about double standard (reading Madame Foschi) and it turn me confuse because maybe the difference that I suppose exist doesn't exist. If it is the case I'would think that there are only differences in the social identity complexity (Roccas & Brewer), configured by different groups to witch the individual belong   

    David Dunaetz

    Take a look  at Joseph Berger's Expectation States Theory which describes the conditions under which people are assigned various levels of status. Social Identity is primarily concerned about what we do to manipulate or maintain how we perceive our own status. Expectation States Theory describes how cultural norms assign status to individuals.

  • Panos V. Petrakis added an answer in Beetles:
    Can anybody send to me some Bark Beetles (Coleoptera: Scolytinae)?

    Dear Sirs,

    I am from Poland, and I am interested in Bark Beetles. In my country we have about 120 species of Scolytinae (only). I would like to make collecion of bark beetles, but not only from Europe. Our fauna is pure compared to other parts of the World. I am writing to enquire about mayby someone has unnecessary  or in excess bark beetles and can share them with me. Beetles can be determined or not (better det.), can be in alcohol or dry. Of course I can sand some species from my collection (speciments only from Poland, but determined).
    Should you need any further information, please do not hesitate to contact me.

    Yours faithfully,
    R. WItkowski

    Panos V. Petrakis

    I can send you bark beetles from all over Greece. In 6cm petri dishes or narrow petri dishes. 

    Bes Regards


  • Francesco Boldrin asked a question in EMI:
    How to batch convert ".emi" to ".TIFF" pictures in Tecnai TIA ?

    Hi all,

    I would like to batch convert simultaneously pictures taken with TIA in a FEI Tecnai electron microscope from ".emi" to ".TIFF" format, instead of doing it one by one. I will appreciate if someone could give me some suggestions.

    Thank you very much


  • Chirag Jain asked a question in Cryogenics:
    Is there ant Transparent material that can sustain cryogenic temperatures?

    Is there any transparent glass or plastic that can be used to observe the flow characteristics at Cryogenic temperatures?

  • Shen-Ming Chen added an answer in TiO2 Nanotubes:
    Can we make TiO2 nanotubes on Ti Foil by anodization by applying potential below 10V?

    TiO2 nanotubes on Ti Foil by anodization by applying potential below 10V.

    Shen-Ming Chen

    Anodizing Ti foil can perform in 0.5 percentage HF DI water solution by applying potential 10- 60 V to get TiO2 nanotube.

  • Alvin Vista added an answer in Sample Size:
    How can I estimate sample size by putting values in N= 10*k/ p (don't know how to calculate "p" in my data)?

    Hello Everybody! I feel very good to see the communication here regarding use of appropriate sample size for using binary logistic regression.  My sample size is 390 cases for dependent variable (150 in "YES" category & 240 in  "NO" category ) My Independent variables are 10. So, by applying the formula N= 10*k/ p,     there is one confusion, I am calculating the "p" 

    Question: 1                   Would somebody help me with in how to calculate                                             "p"=????????

    Question: 2                if i focus on 20 to 1 ratio of valid cases to Independent                        variables,then in my case;  i have 390 cases and 10 independent variables, SO, 390/10=     39:1    this is more than 20 to 1.    Is it right??????????

  • Aliabbas A Husain asked a question in Drug Combinations:
    Can BCG be used as therapeutic vaccine ? Can booster shots be used ?

    Very rare studies are reported that have investigated role of BCG as therapeutic vaccine after TB infection. Can Single or booster dose of BCG be used as therapeutic vaccine alone with drug combination?

  • Pritish Ranjan asked a question in Antimicrobials:
    How to distinguish Bacteriocidal activity from Bacteriostatic activity of any antimicrobial compound?

    If i wanted to test whether a given antimicrobial is showing bacteriocidal activity or bacteriostatic activity, which tests i would need to perform? Which techniques will it involve and how reliable and accepted the technique is? Kindly let me know.

    Thank you

  • Hamidreza Sanaeepur added an answer in Planetary Science:
    How does the moon influence life on Earth?
    It is seen that full moon and new moon influence the sea tidal waves, effects the human mind, and it is also said in ancient scriptures that young plants sprout to life under the influence of moon light.
    Hamidreza Sanaeepur
    Dear James,
    I'd like to help, but unfortunately, I don't know any things in this field. My research works focused on industrial membrane separation processes (in chemical plants).
    Sincerely yours
  • Lwfhp Yvl asked a question in Famotidine:
    What suitable analytical method for the analysis of famotidine?

    what suitable analytical method for analysis of famotidine?

  • Yuri Mirgorod added an answer in Microemulsions:
    Could there be a pH difference between dispersed phase in emulsion and microemulsion?

    I want to compare the biofilm-inhibiting activity of a lipophilic substance in emulsion and microemulsion form. The lipophilic substance is slightly corrosive due to its acidity. This property is tested on the emulsion. Could this property be any different on the microemulsion with the lipophilic substance entrapped inside the micelles?

    Yuri Mirgorod

    Increasing the specific surface of the dispersed system leads to increased concentrations of counterions double layer. This affects the pH. The phenomenon is called the effect of suspensions or emulsions. The pH of the suspension is different from the pH of the filtrate.

  • Abdul Ghafoor added an answer in Soil:
    When soil solution is concentrated four times, K-Ca activity ratio in solution will change?

    As we know that activity ratio is K /Ca or K /Ca+Mg  is influences soil solution.

    Abdul Ghafoor

    When the solution is concentrated, there is strong possibility that the K : Ca will increase in arid region calcareous alkaline soils. Because upon conc., the Ca ions will tend to form first ion pairs and then precipitate as CO3 - compounds. Secondly Ca ions will enter into Stern Layer part of DDL which is not considered generally the part of  DDL. Both these factors will decrease Ca ions in soil solution while very very little change will occur in K conc. Hence the K : Ca ratio will widen. However, the clay mineralogy and contents of OM will affect the rate of change. 

  • Vasudev Reddy added an answer in Electronic Engineering:
    Can anybody tell me which type of biasing circuit is preferrable for Inductively degenerated common source amplifier?

    Low Noise Amplifier, IDCS topology

    Vasudev Reddy

    Respected Josef Punčochář ,

    I have mentioned my schematic what I am using, i.e., Inductively degenerated CS topology.

  • Brian Thomas Foley added an answer in Mauve:
    How do I draw a Phylogenetic Tree using Mauve output files?

    I have been using Mauve for whole genome alignment of about 30 E. coli strains. I want to know, could I potentially just straight visualize a Phylogenetic Tree from output alignment files (such as xmfa) or from a "guide tree" file in newick format? Is there an online tool or for a Windows platform that accepts these formats to draw a Phylogenetic Tree?
    Unfortunately, the Mauve user guide doesn't really give much information in terms of how it determines a Phylogenetic tree.Thanks.

    Brian Thomas Foley

    I would question why you would want one "best tree" of 30 strains or isolates within one species.  I suppose it depends a bit on how those strains or isolates were sampled, but in general there has been a lot of horizontal gene transfer, via phages and plasmids and other mechanisms, moving genes around not only within the Escherichia but also between Escherichia, Shigella, Salmonella and other enterobacteria.  This does not mean that phylogenetic analyses are not very useful, but it is often more useful to analyze individual genes or groups of genes separately.  Whether doing the genes separately or constructing a whole genome phylogeny, it can be difficult to compare the right copies of multi-copy genes,  If there are 2 or more copies of a given gene within the genome of each isolate, it may not be obvious which copy in isolate A to compare to which copy in species B.  It could be very useful to construct one "best tree" using a set of core genes such as DNA polymerases, ribosomal proteins and rRNA genes to which trees built from other genes could be compared individually or in groups.

    There are quite a few software packages which build "webs" or networks which give a sort of representation of gene flow between groups or isolates, but for the most part they do now show which genes moved exactly, or the direction of gene flow.  Nor can they answer questions such as "do genes closer to the origin of replication tend to be less mobile than genes further from the origin?".

    The XMFA format is a modification or extension of FASTA format. http://darlinglab.org/mauve/user-guide/files.html  Most phylogenetic analysis programs can read FASTA format, and there are many conversion programs for converting between common formats, but I am not aware of one that can deal with XMFA because it would need to know how to deal with multi-copy genes and other issues.

  • Shen-Ming Chen added an answer in Hydroxyquinolines:
    Is it possible to prepare Zr(iv) nano complex ?

    Is it possible to prepare Zr(iv) nano complex of zirconyl nitrate hydrate with hydroxyquinoline as primary ligand and l-alanine , l- glycine and l-serine as secondary ligands? i am able to prepare this in bulk but not in nanoscale.kindly help me out with this one.

    Shen-Ming Chen

    A manual for the chemical analysis of metals. 

    You can find Zr(IV) hydroquanione complex information.