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  • Chang-Nim Im added an answer in Zymography:
    Could anyone suggest a storage buffer solution for Zymography gel?

    I would like to store it in simple solution but I couldn't remember. Please let me give an advice. 

    Chang-Nim Im

    Thank you, Cristina! 

  • A.K. Asraff added an answer in Buckling Analysis:
    Which element types are used for the buckling analysis of truss elements in APDL and which results can be obtained ?

    i want to do buckling analysis of truss but LINK did not give buckling .

    So need urz guidline 


    A.K. Asraff

    Hello Mr.Mass,

    I fully agree with the method suggested by Mr.Naveen Bhatt.  Buckling is essentially a bending process which requires beam elements for modelling.  Truss or LINK elements lack the bending capability.  However, to simulate the overall truss behavior, the joints have to be coupled in displacement dofs.  Also, the support conditions also should have only displacement dof.



  • Chibuike C Udenigwe added an answer in Bioactive Peptides:
    Can somebody kindly explain how to remove polyphenolics from peptide fractions?
    I am presently purifying some bioactive peptides from processed soybean only to realise it is contaminated with polyphenolic compounds from the bean. I will appreciate a concise answer on how these polyphenolic contaminants can be removed from the fractions.
  • Stephen Cheung added an answer in Anorexia Nervosa:
    Is anyone aware of any studies (even unpublished) checking on hyperactivity-inattention with the SDQ quest on Anorexia Nervosa children/adolescents?

    SDQ = Strenghts and Difficulties Questionnaire

    Stephen Cheung

    Dear Bruno,

    You may be already familiar with these articles:

    • Using the Strengths and Difficulties Questionnaire (SDQ) to screen for child psychiatric disorders in a community sample by Robert Goodman.
    • Eating disorders in children and adolescents. First results of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS) by H. Hölling & R.Schlack. [Article in German].

    Best wishes,


    + 1 more attachment

  • Thomas Nann added an answer in Cysteamine:
    Could you please give me an advice which QD stabilizer can make QDs stable in DMSO?

    Hello. Could you please give me an advice which QD stabilizer can make QDs stable in DMSO? Cysteamine - coated QDs are unstable. Thank you!

    Thomas Nann

    Try NOBF4. It works as in the enclosed paper - we tried it, but did not mention it there.

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Cube-shaped magnetic iron oxide nanoparticles were synthesised and studied with the aim to achieve superior magnetic properties. This study describes a straightforward and simple synthesis method for preparing monodisperse 11–14-nm superparamagnetic iron oxide nanocubes via an ‘effective monomer’ growth mechanism. The as-synthesised nanoparticles are insoluble in water. However, substitution of the non-polar ligands of the particles using a new method that involved an ionic compound generated colloidally stable and water dispersible cube-shaped particles with a very small hydrodynamic diameter. The cubes displayed superior magnetic properties over spherical particles.
      Australian Journal of Chemistry 01/2014; 67(4-4):663-669. DOI:10.1071/CH13595
  • Qi Yang added an answer in T-RFLP:
    What is the proper way to analyse the T-RFLP data?

    Currently, I haveT-RFLP raw data. I have used Mica3 to export all of the genera. I used three enzymes to digest my samples. Could you please give me some suggestion on how to further analyse them? Which software should I use to do which kind of analysis? If possible, could you please give me the examples?

    Thank you very much.

    Qi Yang

    Dear Dr. Blaud,

    I used T-Align online tool to perform the bar chart. Yes, you are right. There are too many TRFs to feed into one bar chart.

    I read your paper again and would like to ask some questions:

    1. after the T-Align, I got three files. Which one I should use to check and remove the TRFs (<0.5%)?  The comparison one or the consensus one (see the attachments)?

    2. Once I found there is a area% <0.5 in any one of the 4 samples, I will remove this TRFs? Is it correct? After this, the profile of the TRFs for each sample will be changed. Then I need base on the remains to recalculate the % to make it up to 100% within one sample? But how to do it? I only have the %, do I need go back to check the input file to find the peak area points for these TRFs and then re-calculate it?

    3. After all of these (if I got a correct understanding), I will have a file that is the "Data from the TRFLP matrices" mentioned in your paper?

    4. Then the square root transformed and similarity matrices were constructed using the Bray-Curtis method.

    5. Then Similarities between samples were displayed using non-metric multi-dimensional scaling (nMDS) plots and dendrograms

    Sorry to bother you  and many many thanks!


    + 1 more attachment

  • Ranya Dakhelalla asked a question in Public Sector:
    How public sector organisations deliver strategic goals and agreed outcomes from their allocated financial resources?

    this is through  balance sheet management in the public sector,

  • Carlos Rafael Picanço added an answer in Think Aloud:
    Could you provide reference of researches about educational programmes that use eye-tracking, psicogalvanic response and think-aloud techniques?

    Could you provide reference of researches about educational programmes that use eye-tracking, psicogalvanic response and think-aloud techniques to analyse their relation with educational results?

    Carlos Rafael Picanço

    Not a specific reference about think-aloud, but a technical one about eye-tracking: The Pupil Eye tracking Platform: http://pupil-labs.com/ have been a great open source tool for the studies I am running.

  • Rami Alrezk added an answer in Predictive Analytics:
    Hello, I am working on building the predictive analytics model for diabetes. For that, I need dataset. Can anyone help me please?


    Currently, I am working on building predictive analytics model to predict early diabetes by comparing healthy person habits and symptoms with diabetic patients.There will be few other components of my prediction (that I can not share right now) I am certain that my model and algorithms will work perfectly and provide an accurate result. As you know, data is an important part for the accuracy of the model. Therefore, I need the dataset for training and testing of my model. I have already built the concept and mechanism to provide real time prediction. I would appreciate if someone can help me getting the dataset that includes good amount attributes.



    Rami Alrezk

    Consider contacting the ACCORD trial investigators which is randomized, multi-center, double 2 X 2 factorial trial in 10,251 patients with type 2 diabetes mellitus. 

    The website is https://www.accordtrial.org/public/index.cfm 

    Which predictive model you wanna use and what are you trying to predict exactly? good luck 

  • Thomas Nann added an answer in Gold Nanorods:
    Why do some long chain molecules (in this case MPEG-SH) prefer to attach itself to the end of a nanoparticle (nano-rod) where the curvature is higher?


    I am following the method published in this paper (link: http://pubs.acs.org.libproxy1.nus.edu.sg/doi/suppl/10.1021/cm101155v).

    Why do some long chain molecules (in this case MPEG-SH) prefer to attach itself to the end of a nanoparticle (nano-rod) where the curvature is higher, while the shorter chain molecules (CTAB) prefers to attach to the side where it is more flat. 

    Thomas Nann

    In general, the system tries to minimise its surface energy by adsorbing ligands that result in the minimal energy. I'd suspect it is just a steric effect: since mPEG-SH is blukier at its "tail" than CTAB, you get better coverage on a curved surface.

  • Adam B Shapiro added an answer in Protein Estimation:
    Why is my ammonium sulphate protein precipitation not working properly?

    I started with partial purification of amylase using ammonium precipitation technique.While going for step by step saturation the recovery of protein was less than 10% of the crude amylase.So i started with 20ml crude enzyme direct 100% saturation.The precipitates were dissolved in 500ul of phosphate buffer and poured into dialysis bag,dialysis bag was dipped in phosphate buffer.After 24 hours there were  crystals in the beaker contain buffer. I changed the buffer and kept for another 24 hours yet  another day i see the crystals in the beaker This process continued for a week. After a week also some crystals were seen in the beaker but i startet with the protein estimation. I was expecting atleast 80% recovery but again i got only 12% recovery.....the quantity of protein had also increased from 500ul to 1ml

    Adam B Shapiro

    The volume increase of the sample was due to the sample having a higher osmolarity than the dialysis buffer.

    I would guess that the crystals are ammonium phosphate, although this is not consistent with the high aqueous solubility of that salt. If your sample had a lot of magnesium or calcium, the crystals could be the phosphate salts of those ions. In any case, as Viktor Butnev said, a different dialysis buffer is warranted to avoid the crystallization. Many other buffers are possible. Ammonium bicarbonate is useful for mass spectrometry, or when the sample is to be lyophilized, because it is volatile. Tris or HEPES are often used for general purposes.

    Since you are not fractionating by ammonium sulfate precipitation, maybe you should just skip this step.

  • Ajay Vijayakumar added an answer in Nanotechnology in Drug Delivery:
    For oral administration to rats, what solvent should I use to disperse my formulation uniformly?

    My nanoparticles are coated with chitosan and the freeze dried nanoparticles are not able to be dispersed in water. It forms some flakes, which is impossible even to suck through the needle.

    Ajay Vijayakumar

    Thank you! Are their any references for this?

  • Chibuike C Udenigwe added an answer in Bioactive Peptides:
    Does anyone know a method and protocol for peptide fractionation and purification by column chromatography?
    I need to know the protocols for peptide fractionation and purification by column using Sephadex or DEAE, and also the eluent for getting various active peptide fractions for FPH (fish protein hydrolisate).
  • Yawar Abbas added an answer in Ohmic Contacts:
    Any advice on the switching mechanism? The file is attached here.

    Dear Colleagues

    I have a question regarding gradual I-V curve in ReRAM. Actually the Top and bottom electrodes are Au and ITO, respectively. The insulator is polymer but I got gradual curve, what should be the inferred switching mechanism considering that Au is not an active electrode? In log-log plot it shows ohmic contact with slope of 1.2, but I think it shouldn't be filamentary because the change is not abrupt.

    Would you please give me a comment?


    Niloufar (Neli)

    Yawar Abbas

    If you are getting some characteristics like the characteristics of device I have attached here then I may help you.because the I-V you mention in the 3rd  graph is current density Vs voltage. I possible kindly let me know the I-V with current vs voltage

  • Ashrf Abdel Galil Anwer added an answer in Biogas:
    When do biogas digesters start to produce biogas?

    i made an experiment in 4 l digester with inoculum 10% V/V, the digester produced biogas in the first week but other researchers say its not possible to produce before about 21 day, any one have an explanation? 

    Ashrf Abdel Galil Anwer

    mesophilic about 40 C, total solids 10% , cow dung mixed with rice straw, C:N ratio close to 30:1

  • Hong Xuesi added an answer in Heterogeneous Catalysis:
    How to control the selectivity of a heterogenous catalyst?

    Is there any specific method which can control the selectivity of heterogenous catalyst?

    Hong Xuesi

    You can find out  the factors that affect reaction selectivity by your experiment or others' paper.and then you can synthesize you catalyst with controlling those factors.

  • Maziati Akmal asked a question in Piezoresponse Force Microscopy:
    Can anyone help in getting piezoresponse force microscopy (PFM) testing?

    I do have thin film samples with thickness of 200 nm to be characterized by PFM.The samples were deposited on Si substrates. Can anyone extend a helping hand? 

  • Ramin Nasiri added an answer in Graphene Oxide:
    What is the origin of graphene oxide fluorescence?

    I wonder if the fluorescence of GO is associated with some by-products of its synthesis.

    Ramin Nasiri

    hi dear/ read this article..

    DOI: 10.1038/srep00792

  • Adrian Yeow asked a question in Accounting:
    Has anybody used Netsuite as part of their accounting IS class?

    Would like to know how you integrated your coursework with Netsuite Academy

  • Rami Alrezk added an answer in Needs Assessment:
    Could be performed an meta analysis for uncontrolled studies?

    Traditionally, the meta analysis perform between two groups (predictor variable)  to identify which group or technique has better or worse than another but sometimes we need to assess an technique, method, and material without presence of comparative studies. Thus, could we do a meta analysis for case series or uncontrolled studies.

    Rami Alrezk

    Yes, Even unpublished research can be included and optimally research from different languages and from around the world to ensure generalizability and lower the chances of bias. 

  • Venkata Vepachedu added an answer in Protein Purification:
    Why bacterial cells were not sonicating properly after a long duration of sonication?
    I have used BL21 DE3 for expression. After overnight induction at 16°C, I have harvested the cells and sonicated at 40% amplitude for 30sec on/off for several cycles, but still my cells not lysing properly.

    Lysis buffer: 50mM Tris(pH 7.40),150mM NaCl,Triton X-100 1%,Lysozme and Dnase (50 mg/ml stock each),10mM PMSF, 5mM DTT,2% Glycerol.

    Can anyone suggest the reason why it is not sonicating properly?
    Venkata Vepachedu

    You can confirm cell lysis by two ways: 

    1. The suspension turns transparent. The turbidity goes down.  If you don't add sufficient DNaseI it also turns dense due to the release of genomic DNA. 

    2. You can observe the sonicated cell suspension under microscope and guess the % of cell lysis. 

    Another factor that affects cell lysis due to sonication also could be the stage of cell. Stationery phase cells need harsher conditions than log phase cells. 

  • Stephen Cheung added an answer in Social Cognition:
    Should we hold people accountable for their mistakes?

    Dear RG friends,

    This is an important matter, for me as researcher and as human being. It is about errors and we know: "Errare humanum est, perseverare-diabolicum".

    Human errors and the adverse events which may follow, are problems of psychology, systems thinking, behavioral sciences and engineering (in technical systems). Understanding, predicting, and modulating human performance in any complex setting requires a detailed understanding of both the setting and the factors that influence performance. The social cognition research on cycles of accountability clearly captures the complexity of the effects and demonstrates the naïveté of the belief that improving society only requires holding others accountable.

    The “culture of blame” never worked. Why don't people just follow the rules, legislation, procedures?

    My starting point in formulating this question was occupational and system safety, but I would like to have your (expert or personal non expert opinions) in a general sense of human accountability in various fields, activities and situations?

    + 1 more attachment

    Stephen Cheung

    I'm glad that Fairouz, Fadel, and Hanno again shed some light on the responsibilities of leaders (including high officials) in this thread of discussion. As humans, they are prone to make mistakes, but, like others, they should hold themselves accountable for their actions. 

  • Rafik Karaman added an answer in Molecular Mechanics:
    Does anyone know how to do the intermolecular as well as intramolecular rotation at different temperatures?

    Can you please help me to do dft calculation for rotation of molecule for a wide frequency ranging in the broadband dielectric area for different temperatures?

    Rafik Karaman

    You should use the reaction coordinate method in which you change an angle in increments and calculate the energy. The DFT calculations are in 25 C. There is no dynamics calculations using DFT. You can use Arrhenius equation  to find the rate or energy barrier at different temperatures.

    The answer by Emil is also right.

  • Michelle Katusele added an answer in Entomology:
    Is there a safer alternate to chloroform for killing wild adult mosquitoes collected using standard collection methods?

    Most of our entomological  collection methods involves adult mosquito collections and storing them dry in silica-filled tubed for processing in the laboratory. However, recently due to safety concerns, we have been advised to cease the use of chloroform to chloroform-kill the mosquitoes before morphological identification and storage. Are there other safer alternatives to use? Any relevant literature on the subject is greatly appreciated.

    Michelle Katusele

    Thank you for all your responses, they were very helpful. Freezing mosquitoes is a very promising alternative, however we mostly conduct our studies in rural areas, most of which have no access to electricity therefore we cannot freeze mosquitoes. Ethyl acetate and CO2 are also possible alternatives we may use. Realistically speaking, from our perspective as a developing country where most services are unreliable, it may be a bit difficult logistic wise, especially with transportation of these chemicals (DG status), timely delivery etc etc.

    Are there any other alternatives currently used in the field that is portable, non-DG and effective with little damage to mosquitoes?

  • Chibuike C Udenigwe added an answer in Food Biochemistry:
    Which is the best method for preparation of protein hydrolysates and bioactive peptides from aquatic animals?

    As per the literature, aquatic animal protein hydrolysates were prepared and evaluated for various bioactivity, but most of the protein hydrolysates were prepared by peptic enzymatic digestion and isoelectric precipitation. I wanted to know in this two methods, which will be the more easiest and most effective method to get protein hydrolysates in larger quantity.

  • Giovani Theisen added an answer in Lathyrus:
    Can limited intensity of leguminous weeds e.g. Vicia spp., Lathyrus spp. & Convovulus help in controlling lodging in high potential cultivars?


    Giovani Theisen

    My opinion (experience). Depending of intensity and moment of interaction between the weeds and the crop, weeds increase lodging in cereals. I worked with wheat and barley in south Brazil- if the competition/interaction occurs in beggining of crop cycle, the crop stiolate and present a slow developement of roots (because the priority is aerial part), favouring future lodging. Othervise, if high-density vetches grow at late, they use the cereal as support, and literally can bring down the plants because of their weight. Here we crop barley and wheat with 17cm between rows, and this problems I cited can occur on high weed densities.

  • P. Pardha-Saradhi added an answer in TBARS:
    Is the high content of sugar in the extract that may interfere in the TBARS assay?

    is that the high content of sugar in the extract may act in the TBARS assay? because i tried to evaluate the antioxidant activity of date fruit using this assay but it doesn't work.

    P. Pardha-Saradhi

    Dear Njayou,

    Please consider the following points:

    (i) MDA in living systems is generally a product of lipid peroxidation;

    (ii) Lipids peroxidation is (generally) directly proportional to reactive oxygen species (ROS);

    (iii)  ROS are generated due to oxidative stress (to the best of my knowledge all abiotic stresses lead to oxidative stress);

    In light of above, lipid peroxidation is a measure of oxidative stress.

    Yes, I certainly agree that anything (be it be plant extract) that inhibits/reduces lipid peroxidation is an antioxidant,

    We can certainly, plot a perfect standard curve by making different levels of MDA  (if available) react with TBA. But, if you want to measure the potential of plant extract to inhibit lipid peroxidation (that results in MDA production), how can one get rid of MDA?

    Point that we need to address is the way we can get rid of sugars from date palm fruit extract or can we have a protocol alternate to TBARS assay?

  • Markel Olabarria added an answer in Evans Blue:
    Can I carry out immunohistochemistry on mouse tissue when the mice have been previously injected with evan's blue?

    I would like to use evan's blue to assess blood brain barrier permeability in my Alzheimer's mice, but I would like to know if the same tissue can be processed   for DAB or fluorescent immunohistochemistry using Iba1 or GFAP primarys, for example.

    Markel Olabarria


    Worth noting evans blue will show in the red channel if you are considering doing immunofluorescence.

  • Mohamed Mihilar Shamil added an answer in Sample Size:
    Is it possible to compute a covariance matrix with unequal sample sizes?

    I'm not sure if this question is correct, but is there a way to construct a covariance matrix for two vectors that have different lengths? If so, how?

    And would it have a size of (m+n)×(m+n) (assuming the two vectors are of length m and n)?

    (25* 5) * (5*25)

    Mohamed Mihilar Shamil

    sampath, look at it like this. what you have is two groups of data of unequal sizes. what you are trying to do is to establish association between these two groups. in statistics group statistics are mainly dealt through t statistics, anova etc. you can look for weighted techniques, ancova etc. 

    another concern: service quality causes mo or mo causes service quality?

  • Mohammad U.H.Joardder (Omar) added an answer in Food:
    What is the maximum drying temperature for foods?
    Is there any limit to call drying or another process?
    Mohammad U.H.Joardder (Omar)

    Safe drying temperature depends on the type of materials. For example, plant-based materials can be dried in such temperature that does not break cell wall drastically.  However, it may make higher drying time.