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  • Houyong Yu added an answer in Cellulose Nanocrystals:
    How can I perform SEM on cellulose nanocrystal film without burning on sample?

    My CNC film was prepared by evaporating in petri dish. Then, it was sputtered with Pt and Pd for 60 sec. And I try to get SEM image at high magnification (i.e. > 150,000x) but the sample always was burn. Actually, my CNC-film start burning at 30,000x. I try to adjust parameters : both "High Voltage" (from 30, 20 and 10 kV) and "Spot" (from 3.0, 2.0, 1.5, 1.0) but useless. 

    Anyone can tell me the technique to overcome this thing ?

    Houyong Yu

    You can decrease acceleration voltage and quickly save the images

  • Muneeswaran Thillaichidambaram added an answer in Microtox:
    Toxicity assay: is it possible to extrapolate the results?

    When working with the microtox assay (in vitro testing system that uses bioluminescent bacteria Vibrio fischeri), is it possible to extrapolate the concentration of the tested compound/extract on higher organisms?

    For instance, giving 400mg/kg body weight of an certain plant extract to a rat, what  is the analogous concentration (m/v) to test on the Vibrio fischeri?

    Thank you in advance!

    Muneeswaran Thillaichidambaram

    I agree with Juha Lappalainen  But you need to do wide range assay to find the toxicity of the extract and you can go for narrow range assay. I am currently working on toxicity of PAH to P.leiognathi which has been used as alternative to V. fischeri. I did toxicity test with other organisms too. 

  • Morteza Jamshidi added an answer in Electronic Structure:
    The crystallographic information file (CIF) for La2CuO4 orthorhombic and tetragonal

    I am starting to computationally study the electronic structure of La2CuO4 using DFT+U, and I need to have the CIF files as an input. thank you

    Morteza Jamshidi

    Hi Muhamad Darwis Umar , you can make the structure by the Gauss view or crystal maker software but you should know iattice parameters . i think some of the data base so do it!

  • Yoke Kqueen Cheah asked a question in Recycling:
    Recycle protocol for E plates?

    Hi. Did anyone using E-plates for icelligence system before? Did anyone try to recycle the plates. Any protocol to recycle the plates?

  • Srinivas Pittala asked a question in Liver Cancer:
    What are all the important IHC markers for Chemically induced Liver Cancer..?

    Dear All.

    I want to do ImmunoHistoChemistry(IHC) for chemically induced liver cancer. Can you tell me What are all the markers specific for Hepatocellular carcinoma.

    Thank you

  • Gordon Chirgwin added an answer in Aggregation:
    Does anyone know what is the ideal (optimum) ratio of fine aggregates to coarse aggregates in a standard concrete mix?

    Any tip or pointers greatly appreciated. Papers, documents, own findings, etc. are all welcome.

    Gordon Chirgwin

    The optimum ration depends on too many factors. It is really volumetric, but concrete is better batched by mass.  The characteristics required of the concrete will determine the appropriate ratio.  A starting point is to use a near maximum density grading of the materials. 

  • Tomáš Mihok added an answer in Animal Nutrition:
    What is the best morphometric method (noninvasive and objective) for evaluation of body condition in overweight and obese dogs and cats?

    What is the best morphometric method (noninvasive and objective) for evaluation of body condition in overweight and obese dogs and cats ?

    Tomáš Mihok

    Thank you for your response Hans-Heinrich

  • Bharath Urs added an answer in Econometric Techniques:
    Can anyone please refer to some materials which will help a person without mathematics background to understand econometrics tools and techniques?

    Can anyone please refer to some materials which will help a person without mathematics background to understand econometrics tools and techniques? By reading those materials a person will be able to determine which econometric technique he/she should apply to solve a given problem also he/she  will be able to interpret the results. Thanks.

    Bharath Urs

    Try reading philosophy of mathematics! If there is no time for that, then your question is directly leading to econometrics textbooks, wherein instructions are given on how and when to use the econometric techniques. Also those textbooks contain useful information on applications in the form of references.

  • Fernando Ortiz added an answer in Optogenetics:
    Does anyone have any experience with UHP-Mic-LED-595 - Ultra High Power LED Light Source from prizmatrix?

    I was trying to find an high-power LED to drive the ArchT optogenetically. Two thorlabs LED (590nm and 595nm) have been too weak for us and we found a high power one on prizmatrix. The representative said that this model might cause some noise in Ephys recording. Does anybody have experience with that?

    Fernando Ortiz

    Hello Shan,
    I am using the UHP-Mic-LED-460 from the same company to stimulate my sample during electrophysiological recordings. At first I had some noise from the source, but then when I isolated all the wires that necessarily go into the faraday cage (simply by covering them with aluminium foil and then grounded) the noise disappeared completely. So, in my experience it is not particularly noisy,

    good luck

  • Juan Luis Muñoz Bellido added an answer in Microbiology Techniques:
    How do I 'glue' microbiological media to the glass slide?

    Maybe someone knows how to "glue" microbiological media to the glass slide. I need a 3 mm thick coating.

    Juan Luis Muñoz Bellido

    We do as follows:

    we leave some drops of melted medium on a microscope slide. Then you leave a cover slide on it as you would do for a wet mount (you may need press it gently to get the thickness you need) and leave until the agar is solid (around one hour should be enough). Then you slide out the cover slide gently, and you have a very thin sheet with the same dimensions as the cover slide. 

  • Filippo Maria Denaro added an answer in Turbulence:
    Which turbulence model is best to predict reattachment length of flow over a step?

    I have few questions if any one can add to it:

    1. I want to run a simulation with experiments done in free surface water tunnel. Which model you think can predict good reattachment length.

    2. I am using turbulent length scale 6mm and turbulent intensity of 5%. If the reattachment length is not close which parameter should i adjust.

    3. I am using 0 pressure gauge as outlet boundary condition. However experiment was conducted in close recirculating water tunnel. Is it correct? or should i use outflow as boundary conditions.


    Looking forward to hear from you soon.

    Filippo Maria Denaro

    before giving you any idea, what about the Re number? What about the wall effects in the experiment?

  • Franz-Josef Hambsch added an answer in Neutrons:
    How do I peform a flux calculation for an Am-Be neutron source?

    I would like to calculate the neutron flux from a 1Ci activity neutron source.

    Please suggest some methods to do it.

    I would like to know the energy of the neutron from the Am-Be Source having Dose of 22mREM/hr.

    I will be very much thankful to you for the reply to above questions.

    Franz-Josef Hambsch

    Maybe this publication is also of some help.

    I just googled Am-Be neutron sources


  • Arunima Haldar added an answer in Economic Crisis:
    Has diversification a bright side during an economic crisis ?

    Diversification has been a lot criticized in the past. Agency theory was mainly used to  give criticisms to the diversification strategy with respect to focusing firms. But during a crisis diversification may alleviate financial constraints of some units of the group , and promote some profitable investments (internal capital markets).

    Arunima Haldar
    thanks for sharing
  • Beleit Bai added an answer in SRTM:
    How can I download SRTM data of 30 m resolution?

    How can I download SRTM data of 30 m resolution for research in remote sensing?

    Beleit Bai

    This link maybe useful:https://www.researchgate.net/post/How_can_I_download_SRTM_data_of_30_m_resolution

  • Tim Straub added an answer in Psychological Contract:
    Does anyone here familiar with Mechanical Turk (MTurk)?

    I need to use it in my data collection. My proposed samples are working employees since I would like to assess their psychological contract breach as a initial study. 

    Tim Straub


    if you need a starting point of how to conduct studies on MTurk i would recommend reading the following paper as guideline for behavioral research on MTurk:


    As guidelines for experiments:




    Insights about the MTurk sample:


    Be aware, that workers on MTurk might be used to studies nowadays, which might influence your results:


  • Kevin Odega added an answer in Antigen Retrieval:
    Could anybody share his/her experience with EdU labelling on paraffin sections after antigen retrieval?

    I'm not able to obtain consistent Edu labelling (I use citrate buffer 10mM pH=6, 15 min at 95ºC). Thank you in advance!

    Kevin Odega

    You might have to revisit your tissue sections. You have to make them thinner, also you can increase your primary antibody incubation time. It can even be left for days if possible. I guess this will help

  • Mohamed Husain added an answer in Spondylolisthesis:
    Is there any study on impact of mobilization on grade I and II Spondylolisthesis at L5-S1 Level?

    type of spinal mobilization technique with outcomes

    Mohamed Husain

    In general, spondylolisthesis is considered a yellow flag/precaution by some manual therapists. I would avoid mobilising the segment itself as any posterior to anterior force may bring the lumbar spine into more extension and causes pain/discomfort. I don't have any articles to support any type of mobilisation but emphasise on strengthening the anterior abdominal muscles and the core in general. 

  • Mike B. Mostovski added an answer in Insect Physiology:
    Does anybody have clear images of adults of sorghum shoot fly, Atherigona soccata?

    I just want to confirm the same with one prevalent sorghum in PAU?

    Mike B. Mostovski

    Hi Kumar,

    Contact my former MSc student Burgert Muller at the KwaZulu-Natal Museum, South Africa (bmuller@nmsa.org.za). These days he is the best active specialist on Atherigona and have access to excellent photographic equipment.

    All the best,


  • Mostafa Agour added an answer in Optics:
    What is the fundamental information required from an light field image to determine or estimate its depth information?

    Hi all, i have read some literaure on light fiield depth estimation and it seems most of them use either resolution information or shading as a parameter to obtain or estimate depth of the scene. Are there other methods that are accurate or that could be used to estimate depth in a scene?

    Mostafa Agour


    You can use instead of depth of a scene by an optical path difference (OPD). Then you well find a lot of optical methods which cen be used to measure OPD such as interferometry and digital holography.

    Hope this helps

  • Sumreet Singh Johar added an answer in Macrophage:
    What would be good house keeping proteins to consider when working with monocyte-derived macrophages (MDMs) uninfected, exposed, infected with HIV-1?

    I am trying to identify which would be the best proteins to use as "house keeping proteins" that maintain their expression level in monocyte-derived macrophages (MDMs). There are three populations: 1. MDMs that have never been exposed to the virus. 2. MDMs that have been exposed to HIV-1 but are not productively infected and 3. MDMd that are productively infected by HIV-1. I would need around 5 proteins to look at. Thank you!

    Sumreet Singh Johar

    I think cytoskeletal proteins such as beta-actin, tubulin are generally good house keeping genes in every cell. So, those two can be your option. 

  • Adnan Ali asked a question in Social Capital:
    Social capital and civil society are only important for development if the state is weak?

    I am not sure if I agree with the argument. Any thoughts?

  • Ian Kennedy added an answer in Practice Management:
    Is it worth publishing in paid journals, but with claimed high impact factor?

    There seems to be rush for publishing articles in high impact factor journals, perhaps to ensure credibility and career advancement. But many journals are paid and they also claim high impact factors. Is this commercialisation or is this the ethical practice to manage journals? What is to be done?

    Ian Kennedy

    First and foremost you should aim your paper for the journals that cater most closely match your target audience. Second, do a reality check with Beall's list of predatory publishers to ensure that the journal is not blacklisted. Third, all things being equal, choose journals with highest claimed impact factors consistent with your belief about how good your research is. Finally, all remaining things being equal, choose a journal that has no or the lowest submission charge. In practice, there is usually one outstanding journal that looks as if it will accept your paper, so just aim for it.

  • Christoph Weber added an answer in Multilevel Modeling:
    What is the necessary number of Iterations for the calculation of a segregation index based on a multilevel binomial model?

    I'm using the Leckie et al. (2012) approach to measuring Segregation.

    Does anyone know recommandations regarding the neccesary number of iterations for the Simulation of traditional Segregation Indexes (eg. dissimilarity index)? In Leckie et al (2012) I only found "repeating the following steps for a large number of M iterations"



    Leckie, G., Pillinger, R., Jones, K., & Goldstein, H. (2012). Multilevel modeling of social segregation. Journal of Educational and Behavioral Statistics, 37(1), 3-30.

    Christoph Weber

    I will try mlwin and compare the results with mplus

  • Yan Shao added an answer in Hepatocarcinogenesis:
    What are the best cell lines of liver for evaluation gene expression?

    i'm have to evaluate the genome expression of hepatocarcinoma cell lines in a special condition .... but i have no Idea which one is best for study... i have worked on human breast cancer but here it's my first time for working on human hepatocarcinoma and i don't know which cell lines i have to choice. i need to have at least 4 or 5 different cell lines but unfortunately most of them are infected by viruses....

    thanks in advance

    Yan Shao

     i think PLC, Hep3B and HuH7 cell lines are best for  genome scan.

  • Morteza Jamshidi added an answer in Charge Transfer:
    How can I calculate the orbital contribution, and nature of charge transfer in absorption and emission spectra using a DFT technique with Gaussian?

    How can I calculate the orbital contribution, and nature of charge transfer in absorption and emission spectra using a DFT technique with Gaussian?

    Morteza Jamshidi

    your welcome , jamshidi.azad.un@gmail.com

  • Benjamin T. Young added an answer in XPS:
    What is the main reason behind the peak broadening or merging of the doublet into a single peak in XPS spectra ?

    for any element in its nanorange on changing the chemical envoirment.

    Benjamin T. Young

    Lior's answer is solid, but I'd say the main reason is instrumental broadening, if charging isn't an issue.  If decreasing the pass energy of the analyzer doesn't show any improvement, you might consider the other three more strongly.  Uncertainty in the photon energy can also be an issue, depending on whether you use a monochromator and the radiation source.

  • Sumreet Singh Johar added an answer in Arabidopsis:
    How can we find out if an Arabidopsis (or yeast or human) protein is likely to be phosphorylated by a SNF1-like kinase (SNF kinase, AMP kinase)?

    How can we find out if an Arabidopsis (or yeast or human) protein is likely to be phosphorylated by a SNF1-like kinase (SNF kinase, AMP kinase)?

    Sumreet Singh Johar

    I worked similar sometime back in checking phosphorylation of a protein by a kinase. I think there are phosphate specific antibodies available that bind to phosphate groups. So, probably you can use Western Blot to check that. For more clarification, you can contact Prof. W. Todd Miller at Stony Brook University, NY (Todd.Miller@stonybrook.edu)

  • Yan Wang added an answer in Atmospheric Dispersion:
    Where to find unsteady atmospheric dispersion data for the validation of CFD models?

    Hi all,

    I am a phd student desperate for some  unsteady atmospheric dispersion data to validate my CFD model and data assimilation methods (include source estimation).

    I have spent a lot of time in seeking data online, and I find the following datasets:

    • CODASC by Karlsruhe Institute of Technology
    • CEDVAL wind tunnel experiment by Universität Hamburg
    • Benchmark tests from Architectural Institute of Japan
    • some datasets for the Gaussian plume model like those collected by www.jsirwin.com.

    Those are all fantastic datasets for steady state dispersion. However, as I have to test my data assimilation and source estimation methods, some unsteady atmospheric dispersion data are needed.

    I noticed that the following three datasets are widely used for source estimation:

    • Joint Urban 2003
    • MUST
    • FUSION Field Trial 2007 (FFT07)

    However, It seems that it is difficult for phd students like me who just start their research career to obtain those datasets? Actually, I have accomplished a little work about CFD modelling and source estimation for atmospheric dispersion. Now I really need the data.

    Could someone give me a hand?


    Yan Wang

    Yan Wang

    Hi Bart,

    Very useful dataset. And the paper is interesting too.

    Thank you!



  • Eduardo Gómez added an answer in Primary Education:
    Do you know what kind of problem face Children when basic primary education is not in mother language?

    (Do you support Education should be in mother language?)


    Eduardo Gómez

    Dear Allauddin Memon Kohistani,

    I have been teaching curricular subjects such as social and natural sciences, and arts through English in Spain to Spanish students whose knowledge of English is very limited, starting at the age of 6.

    My experience tells me that for the first three months or so, they have some difficulties since the language is basically unknown. The first thing they need is get used to the language by working with daily routines. It is also very important, if you are going to work with adapted textbooks, or authentic materials in the foreign language, to implement a systematic program to teach the students how to read and write the language to be learnt.

    Some children will say that they understand NOTHING, they may get frustrated a little bit, but it is you the one who must make the first contacts of the students with these situations less difficult for them by means of friendly-sessions.

    After the hard first months (hard for the students and for you!) you will see how students start to get more actively involved in the sessions, and in time you will be able to develop "normal" sessions.

    As other colleagues have pointed out, you will have students with a better competence in the language that will understand you much better than the others that will act as "natural interpreters" during your sessions at the beginning. I will recommend you to rely on them, because they can be a very good asset for you. However, as time passes and once most of the students can understand you in the foreign language, I would not promote this attitude, since "translation" is not required for a proper learning of contents in a foreign language.

    One last tip: if you have been a content teacher in your mother tongue before, you must bear in mind that teaching a subject in a foreign language is NOT the same as teaching it in the mother tongue: you need to use a special methodology, that integrates the teaching of both content and language, which is CLIL (it also includes other dimensions such as cognition and culture). Investigate about it, you will find it very helpful and illuminating.

    I hope this helps.