ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

  • Luke Rowe added an answer in Collective Intelligence:
    Does Collective Intelligence Exist?

    Simply put: I'm interested in how groups 'think,' 'learn,' 'perform,' and in turn; how this relates back to the individual.

    In particular, I am currently undertaking a Ph.D. on the topic of 'Collective Intelligence' under the supervision of Prof. John Hattie

    I am fascinated by the idea of expanding the typically individualistic notion of 'Intelligence' and 'Intelligence Testing' and applying these psychological subdisciplines to 'groups' of two or more people.

    For example, is there such as thing as a 'Collective Intelligence Factor' that distinctively represents the intelligence of groups (e.g. two or more people) and if so does this 'c-Factor' set the group apart from the intelligence of its individual members?

    In other words: is the Collective Intelligence of groups greater than the sum intelligence of its individual members?

    How can this collective intelligence be measured?

    Does 'group learning' translate to 'group intelligence'?

    Can we use existing psychometric tests (e.g. IQ tests) to measure and predict cognitive differences in groups?

    What makes one group more intelligent than another?

    Do groups made up of highly intelligent members demonstrate higher 'collective intelligence' and outperform groups made up of low or moderate intelligence members?

    If you have any links, papers, conferences, or general thoughts that would help me explore these ideas; i'd love to hear from you.

    Luke Rowe · University of Melbourne

    Re: Joseph Graca: Yes - group creativity is a fascinating topic. The group ideation / brainstorming literature is interesting here. Although not central to my topic I have had a brief look into it. 

  • John Schloendorn added an answer in Protein Chemistry:
    Can very small peptides (Trypsinized) be precipitated using cold acetone, or is it good for only bigger proteins/peptides?
    Is it possible to precipitate trypsin generated fragments of proteins? By the standard protocols or are there any modifications? Is it a problem if sample has .1% formic acid?
    John Schloendorn · Gene And Cell Technologies

    Does anybody know the answer to the original question though?  Suppose that I have a good reason to really really want to precipitate short peptides with acetone :)  Does that work?  Whereabouts is the limit? 

  • Paulo Magno Martins Dourado added an answer in Coronary Artery Disease:
    Can plasma C-reactive protein (CRP) be used as a screening tool to select among low-risk patients to stratify Coronary Artery Disese (CAD)?

    The high cost of diagnostic methods, even of biochemical markers, limit many of the tools necessary for the diagnosis of CAD, especially if we consider the group of low-risk patients. Can CRP be a cost-effective strategy, as some studies have shown, to stratify these low-risk patient groups and separate which should effectively continue the investigation to elucidate the presence of CAD?

    Paulo Magno Martins Dourado · University of São Paulo

    I agree with the colleague and I believe that the intermediate risk group do CAD is the most important to be screened.

  • Jiawei Chen asked a question in Mortar:
    When calculating the polymer-to-cement ratio of epoxy-modified mortar, should the mass of the hardener be included in the mass of epoxy resins?

    When calculating the mass of polymers to obtain the p/c ratio of epoxy-modified mortar, what components should I include? Should I include the mass of the hardeners? And will the hardening reaction produce any water?

  • Colin James III added an answer in Modal Logic:
    Can any known modal logic system be built from these 14 truth functions?

    The list is below with the decimal and binary labels.

    091 (◇p & ◇q) <---> (p ---> q)
    095 ◇p
    106 ◇(◇p <---> ~□q)
    111 ◇p <---> (q ---> p)
    123 q v (◇p & ~□p)
    127 ◇p v ◇q
    149 □(□~p <---> □~q)
    159 ~◇p <---> (~p & ~q)
    167 ◇p ---> (p & ◇q)
    175 ◇p ---> p
    183 ◇p ---> (◇p & ◇q )
    191 p <---> (◇p v ◇q)
    213 (□p v □q) v ( ~p & ~q)
    234 ~□p & ~□q

    Notice that the 2-tuple of "00" does not appear in these base functions.

    Colin James III · Ersatz Systems Machine Cognition, LLC

    If a pair such as the set {F, 0} or the set {1, T} makes no sense, then there is little point in my trying to explain what I am doing until such time as I can find some physical system or aspect of such circuits that needs a paired evaluation. 

    If one has no use for paired evaluations then one probably has no use for a modal logic such as the one about which I am asking.

  • Jinkoo Kim added an answer in Fish:
    Can anyone help me on growth parameter of fish?

    Currently, I'm working on golden spotted mudskipper (Periophthalmus chrysospilos) and found that M/K =2.6. Is this value is still acceptable? the suggested value of M/K should be in the range of 1 to 2.5 (Beverton & Holt, 1957).

    if not what might be the suggestion for me to fix this?

    Jinkoo Kim · Pukyong National University

    First of all, I think it is most important how your estimation values of the natural mortality and growth rate are accurate. Very frequently, we mistakenly estimate K and M values. It needs to reinvestigate your estimation values again.

  • Yusaku Nakabeppu added an answer in Secondary Antibodies:
    Do you know the best way to immunostain 8-oxoG?

    I've tried the immunofluorescence of oxidized DNA damage, 8-oxoG, so many times but I've never succeeded. At first, I did my routine immunostaining like 4% PFA fixation, 0.2% NP40 permeabilization, 2% BSA blocking, primary, and secondary antibody reaction. Next, I tried cold-methanol fixation and permeabilization. Furthermore, heat block (80 degree) or 2N HCl denature method were also applied. However I've never detect 8-oxoG in nuclei (in some cases I could find them in cytosol, perhaps mitochondiral 8-oxoG). I really want to see them in nuclei and establish positive control for further experiments!
     If you know any good protocol, please tell me in detail. (e.g. both denature "heat shock and HCl treatment are needed for X min, Y degree, and Z min, respectively!)

     I've referred the following paper. And the antibody is sc-130914 (Santa Cruz).

    Yusaku Nakabeppu · Medical Institute of Bioregulation, Kyushu University

    Dear Naoto

    Please completely follow the protocol described in the above mentioned Refrencce with the antibody from JaICa, (N45.1), RNase treatment.

  • Mostafa Darwish asked a question in Digestion:
    Do anyone know how to digest tissue,blood & urine samples for ICP-OES ??

    To determine pt content in tissue , blood & urine by ICP-OES they need pre-treatment and to be prepared that is called digestion process,, it supposed to be made by mixture of nitric acid and HCl ... i don't know the exact procedure for the best results on ICP-OES.

  • Arthi Veerasamy asked a question in Aging Population:
    Does reliability of a questionnaire depends on age of the population?

    I am wondering whether reliability of any developed questionnaire depends on population, especially their age. My sample is stratified into rural urban; and higher and lower socio economic groups. Does this affects reliability of the questionnaire? The reliability of pilot questionnaire without stratified sample was good but the final questionnaire with bigger sample ended up with cronbach's alpha of 0.642. What would be the reason? The age of my participants was between 12-15 years.

  • Raveendra Nath Yasarapu added an answer in Climate Change:
    Is it time we shift emphasis from technological solutions to climate change & focus on the 'Human Dimension'?

    Isn't the obvious solution and elephant-in-the-room 'BETTER HUMAN BEINGS'? Shouldn't the focus be on better human beings rather than better technology? Is it not obvious that nature can heal itself, if only left alone, and it is we humans who need regulation? Many natural parks managers do just that; seal off the area from human interference to let nature heal and recover. It is classified as 'Strict Nature Reserve"by IUCN. Complacency and inaction are not advocated here, as many have misunderstood, but the shifting of focus from technology to the human being. As technology is no match for human greed, isn't introspection & restraining ourselves more relevant than developing more technology, which caused the mess in the first place, by making it easy for a few to consume more? Since technology is only a short term quick fix which fails after a short time, isn't the real problem our addiction to material consumption & our lack of understanding about human nature? Isn't developing more technology sustaining the addiction instead of correcting it, leading to more complex problems later on, needing more complex technological quick fixes like higher drug dosages, more ground troops & equipment, (along with their debilitating side effects) in the future? Isn't this the vicious addiction circle we are trapped in? As researchers, do we merely buy more time with technology OR go to the very root of the problem, the human being?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?

    " Our studies must begin with our selves and not with the heavens. "-Ouspensky

    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests.

    We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions by now, given the amount of money plowed into finding such solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    The Mind is the Final frontier.

    Raveendra Nath Yasarapu · Technische Universität München


    I am afraid you are emphasizing the dark/lower side of the human being. The bottom of the pit. Why not consider the brighter side pointed out by great men in the past and now? If we go purely by what science says, people as selfish , manipulative individuals should abandon their families and start living hedonistically like animals. What about families, society, of culture and values being passed on to the next generations? Isn't this is what sustainability is all about?

    IMHO, the objective of the human experience is to raise ourselves from the lower to the higher. Occasionally the lower predominates, like you have said, but let us not get carried away, even if temporarily. Let us dwell on the higher, nobler side. Also we cannot/should not rule out the esoteric and the philosophical, since that is where some of the brightest and noblest ideas and men have come from.

    Also why dwell on the evil of the Nazis, Stalin and Putin when there are a plethora of great men to derive inspiration from? Please consider this.


  • Richard H Bentham added an answer in Thiosulfates:
    Are there any bacteria which can grow on Thiosulfate Citrate Bile Salt agar (TCBS) apart from Vibrio spp. and may give similar colonies to Vibrio?

    I had isolates on TCBS which thought to be Vibrio spp. later identified otherwise!

    Richard H Bentham · Hindmarsh Water Treatment

    Hi Salah,

    I think Pseudomonas and some enteric bacteria will also grow, but they will probably not appear on the plate as quickly, and should appear morphologically different.



  • Ljubomir Jacić added an answer in Scientific Research:
    What are the best ways to assess/evaluate the performance of research centers/institutes?
    Norms, indications, Measurement weights, impact assessment , etc.
    Ljubomir Jacić · Technical College Požarevac

    The performances of research institutes depend on research management. Here is fine reading about Metrics are no substitute for good research management! You can’t measure human skills the way you do engineering systems, Robert Dingwall and Mary Byrne McDonnell observe in the article.

  • Vivek Chauhan added an answer in OGTT:
    What test do you recommend for screening of undiagnosed diabetes in a rural setting?

    I was reading the ADA guidelines, which say that HbA1c diagnoses fewer cases of undiagnosed diabetes than fasting plasma glucose (FPG), which in turn diagnoses less cases than oral glucose tolerance test (OGTT). Shall we go for all three FPG, HbA1c and OGTT in the first go? What would you do if you do not want to leave any patient of diabetes undiagnosed?

    Vivek Chauhan · Dr Rajendra Prasad Government Medical College

    @ S Charles Bronson: I agree with your statements fully. Go for the test FBS if the patient is fasting, go for RBS if the patient is non-fasting. If they are negative, go for the other tests like A1c and 2 hr PPG.

    What I am planning is a prevalence study in a rural area. My objective is to find the prevalence of undiagnosed diabetes in a rural area. My sample size would be near 1000 randomly selected subjects from a population of 50000. 

    Now, I need a reliable approach fitting within the ADA and IDF guidelines so that I can estimate the true prevalence of undiagnosed diabetes in this population.

    Unfortunately, use of glucometers won't fit within the guidelines.

    Remember, I have sufficient funds with me! The answer that I am looking for is one of these:

    1. Shall I call the selected subjects to the subcenter in the fasting state for testing and perform FPG only?

    2. Shall I perform FPG and OGTT when they come?

    3. Shall I perform FPG, OGTT, and HbA1c in the same sitting?

    4. Shall I do only one of the above tests and call them again if the test is negative to perform the other tests? Will they come again if they know that the first test is negative?

    4. Do I go to their house and perform random blood sugar + A1c first? will they come fasting for FPG and OGTT if they know their RBS and A1c are negative??

    Doing research if rural areas is not easy. I have to contact 1000 people through my field staff. I should be very clear of my methodology before I contact the first person. If I have only one shot, which one of the above choices is the best to achieve my objective stated above i.e. prevalence of undiagnosed diabetes in the rural population? Remember! I am not hitting for the tip of the iceberg, I want to go for the whole iceberg submerged under the water :)).

    Please give your comments...

  • Martin J. Steinbauer added an answer in Terpenoids:
    How do I aquire synthetic terpenoids for use in bioassays?

    We are keen to acquire up to 1 mL of the following terpenoids for use in olfactometer bioassays with beetles and possibly in baits for use in field studies relating to pollination:

    - bicyclogermacrene

    - gamma-elemene

    - Beta-elemene

    - Beta-gurjunene

    Does anyone have these compounds or know from where we could source them - and it a reasonable price? (USD5,000 per mL, the commercial rate for Beta-elemene, is prohibitive.)  We would be interested in a collaboration with anyone who might be willing to supply standards gratis or at "mate's rates".

    Martin J. Steinbauer · La Trobe University

    My colleague, Assoc. Prof. Noel Davies (University of Tasmania), checked the SciFinder database and could only find beta-elemene (at USD5,000 per mL).

    As suggested by another colleague at Lund University, we will contact other chemist colleagues to ask whether they could synthesize some of the compounds for us.

    In the meantime, we will consider a range of other experimental approaches to investigate the role of olfaction in attraction of beetle pollinators in our system.

  • Deborah Jean Verran added an answer in Market Orientation:
    Does someone know a good measurement scale for autocratic leadership style?

    I am searching for a scale to measure autocratic vs democratic or liberal leadership styles. It is one factor amongst others so it should be as short as possible. My last attempt was based on Kassim 2011 "market orientation and leadership styles..." and had 9 Questions but that seems to be a source that is not ranked well enough. Is there a validated alternative that you know of? Thank you in advance!

    Deborah Jean Verran · Royal Prince Alfred Hospital

    There are a number of questionnaires you can try using and it would be useful to see if any of them have been validated.

    Here is an example of a questionnaire-


    Here is an example of research on the topic-


  • Marcos Paulo Thomé added an answer in Gills:
    What is cause of the shortening lamellar disorder in gills of fish?

    I'm looking for the cause of this disorder.

    Marcos Paulo Thomé · Faculdade Redentor

    the absence of vitamin C may enhance the effects of stressors mentioned by Alaa Eldin Eissa. Note that compensatory defense mechanisms may,
    however, compromising the gill function,
    depending on the process severity.

  • Marcos Vinicius Santana asked a question in AutoDock Vina:
    Choosing best for after docking?

    My question is not how to choose the best binding pose per se, but do I need to based on any criteria? 

    For example, If I find that the best pose for my most active ligand is the pose with minimal binding energy. What should I do to analyze my other ligands? Look only for the pose with the minimal binding energy?

    I'm asking this because I screened a library of 20 molecules with known activity. For the most active I selected the pose with the minimal binding energy to analyze. But my second best molecule (I already know it is active experimentally) only showed a promising complex after 15 binding poses (I calculated 20 poses for each ligand). 

    In case this helps, I used autodock vina.

  • Yin Zhang added an answer in ImageJ:
    ImageJ date stamp possible?
    I have been taking pictures of a growth over the period of 4 to 6 weeks. I have pictures from different days (time) points.
    I have placed the different pictures (.tiff) in stacks and made movies. They look very nice but they would look even better if I could write the date of the picture on the top of each picture, to be able to see it (show it) on the movie. Any ideas? I have already seen the Time Stamp function but this does not help me since there is no metadata attached to the file. Pictures were done with a Canon Digital camera on a tripod. The only thing that I have is the date of creation. Any idea how to do this in ImageJ without having to write the date in each picture (there are around 40 treatments, each with around 15 to 20 pictures (one per day)?
    Yin Zhang · University of Bonn

    Hi, another easy way is to use Irfanview. 


    1.  Open your photo/a folder.

         Edit -> Insert Text...

    Then you can directly make a setting (fig. 1) and have a preview on your photo.  In my case, it shows the exif date.


    2.  For the folder editing, then you can click:    File -> Batch Conversion    (fig. 2)

    Then click: "Start Batch" .


    Works done. Simple and fast.

    ImageJ date stamp possible? - ResearchGate. Available from: https://www.researchgate.net/post/ImageJ_date_stamp_possible#55e77ade5e9d978acd8b4644 [accessed Sep 3, 2015].

  • Emmanuel Chukwuma added an answer in Clusiaceae:
    Can anyone help with the identification of these plants?

    I suspect Clusiaceae and Crassulaceae species, but I am not too sure.

    Emmanuel Chukwuma · Forestry Research Institute of Nigeria

    I shall check Avicenniaceae in the Herbaraium tomorrow and post a feedback. Many thanks for your suggestions. Yes, I have also been able to identify the second as Laguncularia racemosa since last night.

  • Mervyn Monaheng asked a question in Diabetes Mellitus:
    What is the relationship between disease and quantum energy?

    Energy Therapies and Diabetes Mellitus

  • Ahmed Shaker added an answer in Amines:
    How can I react 1,2-dichloroethane with secondary amine?

    reaction of 1,2-dichloroethane with secondary amine will happen with one chloride or with both ??

    Ahmed Shaker · Nahda University in Benisuef

    the result of the reaction will be HOW ???

  • Liliana Bergoglio added an answer in Thyroid:
    What are the different types of methods & procedures used to determine a human thyroid profile?

    ELFA  or any other methods

    Liliana Bergoglio · Hospital Nacional de Clínicas, Córdoba, Argentina

    Currently the most popular are automated chemiluminescent and  electro quimiluminiscent  platforms. Follow by ELISA, RIA ( in very special situation  to measure Tg in TgAb positive patients) , and in other some special cases, mass-spectrometry,  the last one of high costand  proposes for reference laboratories.

  • Miguel Angel Callejas added an answer in Boating:
    Is immigration to Europe deserved risking the lives to sinking or to stay in the countries that are burning and destroying in wars?

    Thousands of people (children, women, youth) were dead after ships and boats crowded with illegal migrants sank in the Mediterranean. The media and authorities described grisly scenes of bodies floating and submerging in the waters.
    About 400000 illegal migrants reach Europe during 2015.

    - Is the living in Europe worth so that the person risks the live of his family members?
    - Can Europe absorb such large numbers of immigrants?
    - How to solve the immigration problem?

    Miguel Angel Callejas · Universidad de Sevilla

    Dear Qasim,

    That image is very sad...my dear friend, please ed

  • Lovorka Stojic added an answer in RNA-Seq:
    Has anybody tried TrueSeq stranded total RNA seq?

    Anybody tried true seq stranded total RNA seq (Illumina) for lncRNA identification and gene expression analysis after their depletion?  thanks!

    Lovorka Stojic · University of Cambridge

    Some people use polyA+RNA without Ribozero depletion, did u see the difference in your experiment. How deep did you sequence ? IS it pair end seq? Thanks

  • Madani Brahim added an answer in Foam:
    Which blower is recommended for experimental studies of fluid flow and heat transfer through foam?

    I have acquired centrifugal blower of 0.5 HP. Foam sample has pore density of 10 PPI. Unfortunately all the air is subjected to back flow and on the outlet side I am not feeling any air. Is it because of wrong selection of blower? Should I use suction blower instead of centrifugal blower?

    Madani Brahim · University of Science and Technology Houari Boumediene

    Hi Vipul

    Mancin et al have worked on forced convection in metallic foam with a large domain of grade "PPI". In their experimental devices, they have used an air screw compressor which allows a pressure equals 7 bar at the inlet of the test section.

    For further informations, this is the page of Macin in researchgate:


  • Gino Tesei added an answer in LIBSVM:
    How do we interpret the output of LIBSVM?

    My problem is multiclassification. It has four classes.

    I know that using one-one algorithm 6 binary classes will be formed and for one to rest algorithm 4 binjary classes will be there.

    Libsvm is using 0ne-one approach.

    When I use LIBSVM for classifiaction task it is showing last few lines as follows:

    optimization finished, #iter = 553
    nu = 0.100522
    obj = -1480.765685, rho = -1.798735
    nSV = 58, nBSV = 19
    Total nSV = 58
    Accuracy = 96.4539% (136/141) (classification)

    Is this output and accuracy is the final overall output of the model? or it is the output of last binary class?

    Also, here accuracy means F-score?

    Gino Tesei · Politecnico di Milano

    Dear Krupal, 

    obj is the optimal objective value of the dual SVM problem. rho is the bias term in the decision function sgn(w^Tx - rho). nSV and nBSV are number of support vectors and bounded support vectors (i.e., alpha_i = C). nu-svm is a somewhat equivalent form of C-SVM where C is replaced by nu. nu simply shows the corresponding parameter. Accuracy is # correctly predicted data / # total testing data × 100%. More details are in the following document 


  • Florian Ebner added an answer in gDNA & Plasmid Isolation:
    Which are the criterias to display off-targets results in crispr.mit.edu website, when designing gDNAs?

    I am using http://crispr.mit.edu/ webstite to design some gDNAs, and I have a question regarding the off-target results that is displayed.

    When I enter my sequence this website give me some gDNA and its off-targets, however my actual on-target is not listed. I know that the platform may recognize your input sequence and discard the actual on-target, but in this particular situation the platform marks my on-target as unknown. I would appreciate if someone could give me any explanation about the criterias to display off-targets results in this website.

    Florian Ebner · University of Vienna

    Sometimes on-target is just defined as unknown ... I also had the same confusion, but it also was not shown in the off-targets. At least it was like that a few times - off-targets where always indicated with some mismatches. If it's the on-target, it should be a complete match ... it's not really logical for me ;)

  • José Rafael Padilla Alvarado added an answer in Anthropometric Measurements:
    Does anyone have specific information on children's Field Test players considering the somatic maturation?

    Does anyone have specific information on children's Field Test players considering the somatic maturation?

    José Rafael Padilla Alvarado · Universidad de Los Llanos Occidentales Ezequiel Zamora, UNELLEZ

    Perfect friend. Thank you. You can send me the link where this methodology Matzudo ?.

  • Ismaila Aliyu added an answer in Graphene:
    What is the effect of acetone on Graphene ?

    During transfer of graphene from Cu foil to SiO2 we use acetone to remove PMMA from graphene surface, is there any effect of acetone on graphene's chemical or electrical properties.

    Ismaila Aliyu · King Fahd University of Petroleum and Minerals

    @Minas. Are you aware of the difference between graphene and graphene oxide (GO)? When you said graphene is almost insoluble in acetone, do you mean the same for GO. I am asking because it looks like you used the paper that discussed the dispersion behavior of GO in various solvents to support your statement on graphene solubility.