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  • Vaibhav Pawar added an answer in MATLAB:
    Has anybody written code in MATLAB to process image of envelope to study wrinkling details?

    I have a model of envelope patch which I would like to stretch in biaxial directions and want to study wrinkling amplitude and wavelength. I would like to write code in MATLAB. If anyone has developed such code please help me out.

    Vaibhav Pawar · Indian Institute of Technology Bombay

    Thanx Hayder 


    Vaibhav Pawar

  • Emma Mangan asked a question in Memory:
    In what ways can differences in memory processing lead to inaccuracies in eyewitness testimonies?

    I am currently looking at eyewitness testimony and am interested in what causes inaccuracies and differences between statements. I am not yet sure where to start my search and would appreciate if somebody could help my understanding of how memory processing can differ. 

  • What are the rights of refugees under international law?

    The greatest challenge facing refugees arriving in the developed world is to convince authorities that they are, in fact, entitled to recognition of their refugee status.

    Subhash C. Kundu · Guru Jambheshwar University of Science & Technology

    The rights of refugees are:

    1. Equality -- Treating equal

    2. Settlement -- Settling them as if they nationals

    3. Growth opportunities -- Providing opportunities to grow

    4. Assimilation -- Accepting them in main stream

    India faced this problem in 1947, a big number of refugees came to India. India settled them with all avenues in India. But still differences are prevailing.

  • Asa Wu added an answer in Western Blot:
    What is possible cause of faint/dissapeared in the middle part of band and non-straight line band in Western Blot?

    Could you kindly help me to specify what could be possible cause of my problem with band in Western blot as showed in my attach picture? picture 1 is 40 kda, picture 2 is 60 kda.

    1. Some time, the band is not straight, a bit deformed like the leftmost band in the picture 1.

    2. I often get the band which has faint or disappearing in the middle part as most band in both picture and especially second rightmost band in the picture 1.

    I use Biorad's Mini-Protean system, homemade SDS-PAGE gel: 12% resolving and 4% stacking, SDS running buffer, running at 60V for 10min then 200V for 39min, fresh Towbin with 20% methanol transfer buffer, clear bubbles with glass stick, transferring at 100V for 1hr. The membrane is PVDF, wet with 100%methanol for 1min and transfer buffer for another 15min.

    Thank you so much


    Asa Wu · Mahidol University

    Thank you for your reply, Saugata.

    I use only 10 ug of my sample. May be, I'll try 20 ug next time. Not sure is bubble. I think I have get rid all bubbles by rolling glass stick.

  • Gunawan Indrayanto added an answer in Lysine:
    How can we measure the amount of spots in TLC?

    I want to detect and measure approximately amount of lysine with TLC, how can I measure it (lysine), can anybody introduce method or software?

    Gunawan Indrayanto · Airlangga University

    Please open this data base, you will find many methods for determination of lysine by using TLC:


  • Giovanni de nola added an answer in MDCK:
    Are MDCK or HeLa cells sensitive to asparaginase-induced apoptosis?

    Dear all

    I'm trying to study the capacity of a molecule in protecting cells from the pro-apoptotic effect of the asparaginase added in the medium.

    I have in stock only HeLa cells and MDCK.

    Does anyone have any idea if above mentioned cells are sensitive to asparaginase?

    Do you have any other cells besides lymphocytes that could be suitable for this purpose?

    Giovanni de Nola. 

    Giovanni de nola · University of Pavia

    Many many thanks, that's exactly what I needed!

  • Praveen Kumar Reddy asked a question in PLS:
    Is there any possibility to resolve High conductivity problem with Cationic Ion chromatographic system?

    Even though i tried to hydate the suprressor with NaoH and milli q, i couldn,t decrease the conductivity to lessa than 2 even retention times are effecting due to the high conductivity Can someone pls help me to resolve the problem. Thank you...

  • Bradut Vasile Bolos added an answer in Stakeholders:
    What are the various mechanisms through which the impact of asset bubbles can be measured?

    Assest Bubble; Impact on various stakeholders

    Bradut Vasile Bolos · University of Buraimi

    There are a variety of measurements possible based on the angle you chose to approach. To name a few:

    1. Assets value loss (total at market value, average per unit, percentage of market value, percentage per unit)

    2. Company failures

    3. Jobs lost

    4. Connected assets value loss

    5. Taxation income lost

    6. Revenues lost, customers lost,

    The list could continue, as more and more stakeholders are facing consequences.

  • S M Ferdous Hossain asked a question in Clustering:
    How to identify important variables before doing any cluster analysis? Any method to extract most important variables from a huge set of variables?

    I am working on classification and clustering problems in R. I need to know the ideas behind choosing important variable groups which have larger impact in clustering. My suspect to check pairwise correlation. Even after clustering, variable weights can be identified among clusters. But I want to know the mining methodologies for the purpose of clustering. How I assess the importance of a variable before performing cluster analysis among a huge set of correlated/independent variables??

  • Hayder Dibs added an answer in ImageJ:
    What would be the best way to analyze stained vs unstained portions of an ROI in black and white images?

    I have all my images (.TIF files), but I was wondering what would be the best route to simply determine staining versus unstained portions of my ROIs. We normally use MCID, but getting the correct density settings that work for all the images has proven troublesome. 

    I began to wonder, since we have no interest in densitometry, if I even need to adjust them, or measure them for that matter. We usually do densitometry, but for this purpose we aren't really interested in that. 

    Would it be as simple as just opening an image and setting the scan area to include all the stained portions of the image? 

    I'm new with MCID, but I am also open to possibly learning with ImageJ, since there are so many possibilities available and it is being used almost universally at this point. 

    Thanks in advance!

    Hayder Dibs · Putra University, Malaysia

    very interesting point

  • Hayder Dibs added an answer in Object Recognition:
    What are the similarities and differences between the pandemonium model and hierarchical model of object recognition?

    The HMAX as dubbed by Tarr (1999) has been described as resembling the pandemonium model, however, in his description of HMAX I found it difficult  to discern the similarities and differences.  I have made contact and I am awaiting a reply but perhaps another researcher can shed some light in the interim. 

    Hayder Dibs · Putra University, Malaysia

    very interesting point

  • Grass Gis: How to deal with the warning concerning Esun during i.landsat.toar job?

    Dear colleagues,

    I'm working with Grass Gis 6.4.4. and learning with 7.0 (GUI interface).  I calculate TOA-reflectance with i.landsat.toar module. But some time I launch the module, the following warning appear.


    My Russian colleagues are sure that I shouldn't pay any attention to this warning as the output TOA-reflectance data is always the same with the data obtained by entering ESUN value for many routine kinds of work. Although they are not sure that it is acceptable for any special image processing, such as DOS atmospheric correction etc. And the problem is that my job is very special without any right for mistake. I have to do many experiments with various image processing to get acceptable results.

    And so I need reliable TOA reflectance data.

    My question are:

    1. Can anyone tell if I can get appropriate TOA-reflectance data without entering Esun value? Can this parameter significantly influence the output data? In what cases?

    2. How in i.landsat.toar module I can enter Esun value?

    3. Why the warning appear not every time but after the same actions and it depend on certain image?

    Hayder Dibs · Putra University, Malaysia

    very interesting point

  • Hayder Dibs added an answer in Simulators:
    How to make simulation of an object/image with know MTF ?

    I want to compare the experimental MTF with true MTF. Can anyone please let me know how to simulate object with known MTF or how to simulate wire with known physical dimension. 

    I will appreciate your help.

    Hayder Dibs · Putra University, Malaysia

    very interesting point

  • Hayder Dibs added an answer in Heavy Metals Removal:
    How to calculate binding efficiency(%) of nanoparticle in heavy metal removal for waste waste water treatment?

     How to calculate binding efficiency(%) of nanoparticle in heavy metal removal for waste waste water treatment?

    Hayder Dibs · Putra University, Malaysia

    very interesting point

  • How do I determine the lead equivalent thickness of non-lead protective aprons for interventional radiology?

    I am aware of the IEC 61331-1 protocol for X-Ray attenuation measurements, both for narrow beam and broad beam geometry. Do you use table interpolation or you calibrate with known Pb samples? Do you get different lead equivalent thicknesses for these geometries? What are the preferred specification of lead equivalency by the apron manufacturers?

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    Thanks for the prompt response

    Regards Hanno

  • What is the optimum weight of carrier based inoculum to apply and the frequency of application for cleaning 1ha soil contaminated with 4-5% crude oil?

    The carrier is charcoal. It contains a consortium of efficient bacteria (10 to power 8-9 CFU/g). The soil was contaminated 7 years ago. The soil is clay loam, pH 8.2, low N, P and organic matter content.

    Awad Galal Osman · Natural Resources and Desertification Research Institute, National Centre for Research - Sudan

    From literature I found that the optimum weight of the carrier based inoculum is  2% from soil weight in a pot experiment and the frequency of application was once for 150 days and the degradation% of TPH was satisfactory.

  • Where can I find MRI database for liver segmentation?

    I would like to find MRI images database for liver segmentation and classification.

    Abdalla Mostafa Zidan · Cairo University

    Dear Dr Surender
    Thank you for your concern, It is really kind of you

  • Remi Cornwall added an answer in Particle Physics:
    No experiment directly observed Quark particle, why do we think Standard Model is a valid theory?

    The Standard Model of particle physics is a theory concerning electromagnetic, weak, and strong nuclear interactions, which mediate the dynamics of known subatomic particles. The current formulation was finalized based on the existence of quarks. There is no way to proof the existence of quark. It is pretty risky to build a theory one something that may not exist. It neither explains force hierarchy nor predicts the structure of the universe. The Standard Model falls short of being a complete theory of fundamental fields. Mathematically, the standard model is a quantized Yang-Mills theory. Because of its success in explaining a wide variety of experimental results, the Standard Model is sometimes regarded as a "theory of almost everything".

  • Jakub Kuś added an answer in Social Influence:
    What is the best questionnaire for condicting research about Facebook?

    I mean something like "Facebook Intensity Scale" (Ellison, Steinfield and Lampe, 2007) or a questionnaire which describes styles and motives of different behavior on Facebook (gamers, social influencers etc.). I would be very grateful for response and some hints. 

    Jakub Kuś · Warsaw University of Social Sciences and Humanities

    Ulf-Dietrich, thank you so much for your pointers - both yours and Adam Joinson's articles are a great insight in my research problem. I'll write you a message about your article which is under review. 

    Besides all, your response is a great pleasure for me. I read your articles and study your work from the beginning of my interest in Internet studies. I also admire your "Social Lab" as a tool for conducting experiments about social media. So thank you once again.

  • Hayder Dibs added an answer in Biometrics:
    What is a good algorithm for Iris Liveness detection?

    I am working on liveness detection of biometrics and I am in need of an efficient algorithm for that. What can be a good algorithm for liveness detection in biometric traits. Where I can find a suitable guidance for the work.

    Hayder Dibs · Putra University, Malaysia

    Very interesting I would like to follow this point 

  • Paul Louangrath added an answer in Didactics:
    Why students do not think critically?

    I gave two mathematical questions/tasks to my students. 

    1. What is the solution set of x2 = 1?

    2. Given that triangle ABC is a right angled triangle. Angle ABC is right angle, and the measure of angle BCA is 60 degree. BD is perpendicular to AC. If CD is 1 unit long and BC is 3 unit long, what is the perimeter of triangle ABD?

    Students' responses to the first question was mostly {-1,1}. When I asked them is it the only correct answer, they said YES. They thought that the universal set of this equation is the set of real numbers R. Even when I said that there are many other possible universal set for this equation, such as {2} if the universe is the set of natural number, {-2} if it universe is the set of negative integers, and an empty set if its universe is the set of even integers, they did not take it into their considerations. They claimed that whenever there is no clear definition of the universal set, the universe of the equation should be the set of real numbers R. 

    To the second task students directly used pythagorean theorem to find the length of BD, and followed by finding the measure of side AB using the sine of angle BAC (which is 30 degree). Finally, they used these facts to find the length of AC, and finally AD. They did not pay any attention to the incorrectness of the conditions given in the problem. The incorrect proportion of BD:BC was ignored. 

    Based on the definition of critical thinking, skills and/or dispositions, I think they do not think critically. 

    Anybody can give an explanation of this phenomena? I need your points of view. If you can show me any theory and research results that can be used to explain this phenomena, it will be a great contribution to me.

    Thanks in advance.


    Abdur Rahman As'ari  

    Paul Louangrath · Bangkok University

    NON RES IPSA LOQUITOR: Both example questions do not demonstrate whether students are capable of critical thinking. If any thing it could demonstrate that these students are weak in basic math skills. One cannot conclude that because they could not answer both math questions correctly, it is res ipsa loquitor (the fact speaks for itself) non-critical thinker.

    CRITICAL THINKING AS AN UNREALISTIC EXPECTATION: It is unrealistic for professors to expect students to think critically at university level when for the past 12 years in students' education, they had been mostly trained not to think, but to remember of thinks taught. In primary school, students are not taught to explore, but to follow rules of behavior: how to behave in society of peers, i.e. students of the same age. At secondary school (high school level), just about when the intellectual development and curiosity begin to take shape, students are taught to compete to get better grade so that they can get into good university. How many courses or teachers in high school teach students to think critically? Once students arrive at the university---approximately 3 months after high school graduation for most people---they are told to think critically.

    WHERE SHOULD CRITICAL THINKING START: It should start at secondary school (high school level). At university level, students could apply their critical thinking ability.

    GENERALIZATION: We should take students as we receive them: smart and less smart, and train them through our teaching process. Good professors generally teach their students to think. Poorer professors just go through the motion in the teaching. If we want students to think critically, professors should interact with students more inside and outside of class.

    In many cultures, there are social distance between professors and students. This gap nurtures non-critical thinking, i.e. students are waiting to be told what to do instead of thinking, exploring, innovating, etc. the challenges rests on the shoulder of the individual professors and their teaching style.

  • Can Anyone suggest any biocompatible materials for coating onto fruits and perishable foods to enhance the transportation and storage life?

    S.E law, Mark N Horensitine 

    Manoj Kumar Patel · Central Scientific Instruments Organization

    Thanks a lot for ur valuable answer but the thing is that I'm using an electrostatic method of charging the water soluble biomaterial.....so the question is solibility of that material in water or some conductive solvant 

  • Do we need in nursing to conduct studies using physiological measures?

    Do we need in nursing to conduct studies using physiological measures? or, we have to keep focusing on the psychosocial aspects in our research? how much is the percentage of nursing research that used physiological measures?

    Mats Christiansen · Karolinska Institutet

    Inspired by Carrieri-Kohlman, V., Lindsey, A. M., & West, C. M. (2003). Pathophysiological phenomena in nursing : human responses to illness (3. ed.). St. Louis: Saunders, I would say a definite yes to nursing's need to conduct studies that use physiological measures. And that these are already taking place.

    Physiological parameters can be a way of assessing nursing interventions:

    • weight/BMI for a weight-loss program;
    • scales to assess pain when doing interventions to help patients with chronic or acute pains;
    • pulse and blood pressure to follow non-pharmacological interventions;
    • following blood-glucose levels in patients with diabetes who have a nurse-led intervention.

    But I cannot give you a percentage that have used physiological measures or parameters. However, a quick-and-dirty search on PubMed with the term "physiological measures" in nursing journals yields some 400+ articles with varied topics ranging from measuring the length of telomeres (PMID: 24977726), to "Effects of live saxophone music on physiological parameters, pain, mood and itching levels in patients undergoing haemodialysis" (PMID: 24980265).

  • Peerapat Kham asked a question in Hela Cells:
    How long are HeLa cells divide after activate from sleep ?

    How long are HeLa cells divide after activate ? 
    I activated HeLa cells from freeze.  I have cultured it for 2 days but it is not full in flask .
    what time i can trypsinize ? 
    i am beginer to culture HeLa cells 
    Thank you

  • Residuals Normal, independent Variables not so much: An Example?

    The assumption in linear regression models is that the residuals are normally distributed, if everything is working properly. Is it possible to have residuals that are normally distributed when the variables are not? The following example should help clarify the problem.

    If you have the equation y=mX+b+e then I want X to be non-normally distributed for any fixed level of y. So if I have fake data, then I might write a for loop for(y in 1:100) to get different levels of y, and the calculate x as uniform for each value of y. Maybe something like x=runif(20,min=1+y, max=5+y). For every level of y, I will get 20 values of x that come from the uniform distribution with a minimum value of 1+y and a maximum value of 5+y. The residuals look sort of normal, but are obviously bounded. I could try another x=runif(20,min=0,max=1)^runif(20,min=0,max=1)/runif(20,min=0,max=1)+y. The residuals look very strange, so this clearly is not a case where the residuals are normally distributed and the independent variable is not.

    I suspect that saying that the residuals are normally distributed is equivalent to saying that the independent variables are normally distributed at any level of the dependent variable. This is not the same as saying that the independent variable must be normally distributed.

    Diana Šimić · University of Zagreb


    This is perfectly clear, and correct. In linear regression (or analysis of variance, or t-test ... or any other general linear model) we model conditional distribution of y (dependent variable) for given value of x (independent variable) as normal distribution with a

    1) constant variance (i.e. variance is independent of x ... that is homoscedasticity)

    2) mean that depends on x in a way that is linear in coefficients (we can use a nonlinear function of x, but function must be linear in coefficients that need to be estimated)

    This is different from the example you provided in the original question where you were looking at the conditional distribution of x.

    We also assume that x is measured without error (or at least that variance of error in x is much smaller than variance of error in y). Ideally x values would be planned or "designed" to achieve the highest power in an experiment. We do it routinely in analysis of variance, but not so often in linear regression.

  • Seyede Farzane Besharat added an answer in Titania:
    How can we control temperature for nanoparticles (for example titania) with 0.1 degrees accuracy in small units or small rooms?

    I want to have small units or rooms that can keep the temperature at a specific value in the range 35 to 65 degrees...with 0.1 degree accuracy...

    Seyede Farzane Besharat · Tarbiat Modares University

    Thank you so much Mr. Amjadi, Mr, Manilal D and Mr. Larrabee for your help.

  • Communications security protocols in e-Government?

    Due my lake experience in communications security protocols I wonder if any one can advice in something related to e-Government or can forward to work in that filed.

  • Will adding more dummies reduce R-squared?

    Hi all,

    I had a regression model with n=5000 approx,

    Yield/ha = f { farm size + input variables }

    The output gave R^2 around 40%

    When i added interactive dummies (5zones * 11 years == 54 dummies) along with above equation, the coefficients had sign and significance as expected, but the R-squared value dipped to 3% (0.03).  Is this a concern, or since variables are significant, i can proceed further ??


    Shuichi Shinmura · Seikei University

    If you tell me the software name and agree to open my results on Research Gate, I can

    analyse your Excel file.

    First row is variable name.  5000 cases are stored after 2-rows to 5001-rows. Dependent variable and 55 independent variables correspond to 56 columns.

  • Can anyone help me to solve the non-linear ordinary differential equation attached herewith by using SLM-Successive Linearisation Method...?

    I am facing problem to solve the attached problem by using SLM method. So please help me to resolve it.

    Kåre Olaussen · Norwegian University of Science and Technology


    I took another look at the paper you linked to: The boundary conditions (2) and (5) are not consistent with each other. Your original problem does not admit a similarity solution, due to the boundary conditions.

    Moreover, you probably want to provide some initial values, Sw(L,0). Equations (1-2) have a solution Sw(L,T) = sqrt(L). Perhaps any initial condition will approach this solution?