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  • Gayan Wijesundara added an answer in SAP 2000:
    How can I analyse a structure for a blast load in SAP2000?

    How can I analyse a structure for a blast load in SAP2000? What is the procedure?

    Gayan Wijesundara · University of Southampton

    Hit the link below. Hope it will help.

  • Haitham Hmoud Alshibly asked a question in Time Management:
    Is Management by Walking Around the Most Effective Management?

    Based on the need for managers to dedicate their efforts to administering and growing businesses, and given the proven effectiveness of objective performance measures, it seems the time for Management by Walking Around is gone. Yet there is one caveat. We certainly don’t argue that managers should refrain from knowing their employees, or that a stroll through the work floor is a bad idea. Rather, we find the regular, intentional interactions of Management by Walking Around do not, in themselves, make an effective management tool. what do you think?

  • Maria V. Kozlova added an answer in Landsat:
    How can I process dark object subtraction of the standard Landsat 8 products?

    I want to know if the standard Landsat 8 products provided by the USGS EROS Center are still needed dark object substraction when I use the digital number as auxiliary variable in predicting SOM variability?

    Maria V. Kozlova · State Oceanographic Institute

    If you use level 1 products you may apply DOS. For SR products you don't need any correction  but topographic if needed

  • Azzam K Almosallami added an answer in Elementary Particles:
    Do photons interact with gravitons?

    The graviton is a hypothetical elementary particle that mediates the force of gravitation in the framework of quantum field theory. If it exists, the graviton is expected to be massless and must be a spin-2 boson. The spin follows from the fact that the source of gravitation is the stress–energy tensor, a second-rank tensor. But by no means is it universally accepted.


    But there are many articles about the interaction between Photon and graviton or graviton-photon scattering.



    How can graviton's mystery be solved?  Should graviton be detectable or like photon (same as photoelectric effect) be able to explain the physical phenomena?

    Azzam K Almosallami

    Dear L. Frankfurt,

    Graviton-photon resulted as a consequence of stress energy tensor. Stress energy tensor resulted from the space-time continuum in SRT. Space-time continuum was proposed basis on objectivity which was adopted in classical physics. From objectivity it is resulted the continuity. Quantum physics refusing objectivity and continuity, and from that it is resulted all the problems in understanding gravity according to quantum theory. Now everything becomes clear and very simple. Now instead of the stress energy tensor, it is the wave-particle duality and Heisenberg uncertainty principle which lead to the four vectors, and all the problems will solve and there is no graviton, it is photon.

  • Haitham Hmoud Alshibly added an answer in Organizational Change:
    How is organizational culture created and sustained?

    How is organizational culture created and sustained?

    Haitham Hmoud Alshibly · Al-Balqa' Applied University

    thanks Rohit, Mossayyeb , and Elisabeth

  • Emmanuel Omolola added an answer in Health Literacy:
    How can I deal with low educated elderly when collecting qualitative data?

    Now, I'm working on health literacy project. I have to collect data from elderly people and it seems that most of them are low educated. It's difficult for them sometimes to express any word/ idea/ ... Therefore, I would like to know how to cope this problem. Thank you.

    Emmanuel Omolola · Capella University

    Yes, in addition to speaking in local dialect, you're to engage those who're able to minimally read and write. To enable you gather health data information and afford them good training sessions to collect health data that are relevant for your research study.

    Good discussion, Arnat!  Wishing you successful research study

  • Sari Lakkis added an answer in Video Processing:
    How can I extract frames out of a video?


    I have used the following Matlab code to extract frames of a video, however, in the folder in which the frames are stored I see that after every five frames (for example), three frames are entirely black (the background of image)!! and this is seen when I change the video but for example the numbers of five and three are changed to others....

    How can I resolve this problem? I really don't want this happens since some data will be missed undesirably...

    my code is : 

    % Open an sample .mpg file

    [FileName,PathName] = uigetfile('*.*','Select the Video');

    file = fullfile(PathName,FileName);

    %filename = '.\003.AVI';

    mov = VideoReader(file);  % make an obj of video (with all video info)

    % Output folder

    outputFolder = fullfile(cd, 'test');

    if ~exist(outputFolder, 'dir')



    %getting no of frames

    numberOfFrames = mov.NumberOfFrames;

    numberOfFramesWritten = 0;


    for frame = 1 : numberOfFrames 

        thisFrame = read(mov, frame); 

        outputBaseFileName = sprintf('%3.3d.bmp', frame);

        outputFullFileName = fullfile(outputFolder, outputBaseFileName);

        imwrite(thisFrame, outputFullFileName, 'bmp');   

        progressIndication = sprintf('Wrote frame %4d of %d.', frame,numberOfFrames);


        numberOfFramesWritten = numberOfFramesWritten + 1;


    progressIndication = sprintf('Wrote %d frames to folder "%s"',numberOfFramesWritten,outputFolder);


    Sari Lakkis · Université de Versailles Saint-Quentin

    You can use opencv library in c++, here is an example code to do what you want, get the "frames per second" and display them again:

    /Read frames from video file
    int main1(int argc, char* argv[])
    VideoCapture cap("D:/Myvideo.avi"); // open the video file for reading

    if (!cap.isOpened()) // if not success, exit program
    cout << "Cannot open the video file" << endl;
    return -1;

    //cap.set(CV_CAP_PROP_POS_MSEC, 300); //start the video at 300ms

    double fps = cap.get(CV_CAP_PROP_FPS); //get the frames per seconds of the video

    cout << "Frame per seconds : " << fps << endl;

    namedWindow("MyVideo", CV_WINDOW_AUTOSIZE); //create a window called "MyVideo"

    while (1)
    Mat frame;

    bool bSuccess = cap.read(frame); // read a new frame from video

    if (!bSuccess) //if not success, break loop
    cout << "Cannot read the frame from video file" << endl;

    imshow("MyVideo", frame); //show the frame in "MyVideo" window

    if (waitKey(30) == 27) //wait for 'esc' key press for 30 ms. If 'esc' key is pressed, break loop
    cout << "esc key is pressed by user" << endl;

    return 0;


  • Azzam K Almosallami added an answer in General Relativity:
    Is not better to find an operating definition of *non inertiality* just provided by detecting accelerations, than to define inertiality??

    According to Newton:

    "An inertial frame of reference is one in which the motion of a particle not subject to forces is in a straight line at constant speed."

    According to Einstein from the Meaning of Relativity:

    "The weakness of the principle of inertia lies in this, that it involves an argument in a circle: a mass moves without acceleration if it is sufficiently far from other bodies; we know that it is sufficiently far from other bodies only by the fact that it moves without acceleration"

    Was this a sufficient reason to reject the principle of Inertia??? And to change it in the form he proposed it?

    Didn't he miss someting in affirming that free falling objects in a gravitational field are  inertial except for tidal effects??

    What is then the definition of an inertial system???

    I think everybody can agree with this sentence:

    if an acceleration is detected by an accelerometer at rest in a RF, the RF is not inertial.

    Is it not that in Physics only the non inertiality can have an operative definition by just measuring the acceleration??

    The acceleration has a dynamical and kinematical definition in experimental Physics and these in classical physics agree, why only the dynamical one was used in GRT???

    Azzam K Almosallami

    Dear Kåre Olaussen,

    The problem here is how to define the classical acceleration according to quantum physics in order to reach to the unified theory. Is Einstein was right by his GR? If not what is the error in GR and led us since 100 years we could not reach to the unified. Now according to my quantized gravity everything in the universe are moving according to the wave-particle duality and Heisenberg uncertainty principle. The Pioneer anomaly and the energy momentum problem in general relativity are related to each other.  According to my solution, there are two terms of decelerations that controls the Pioneer anomaly. The first is produced by moving the Pioneer spacecraft through the gravitational field of the Sun, which causes the velocity of the spacecraft
    to be decreased according to the equation t'=(1-2GM/c^2r)t. The factor of 3 here is resulted according to the group velocity which is no equal to the phase velocity.  This

    deceleration is responsible for varying behaviour of the Pioneer anomaly in Turyshev. The second term is produced by the Hubble’s law which is constant and equals to the Hubble’s constant multiplied by the speed of light in vacuum. This term is resulted according to zero point energy. Review my RG https://www.researchgate.net/post/Can_zero_point_energy_explain_the_rotation_curve_of_a_typical_spiral_galaxy_the_flat_appearance_of_the_velocity_curve_out_to_a_large_radius2?_tpcectx=qa_overview_following&_trid=5595b3d16143258a4a8b45db_

    And review my paper of the exact solution of the Pioneer anomaly, it is exact


  • Andrew Rael added an answer in Escherichia Coli:
    Dear colleagues, does anyone know an ELISA which recognizes E. coli-expressed BMP-2?

    I´m wondering, if anyone knows where to find such an ELISA

    Andrew Rael · IntelliCyt

    Here are a couple options. Hope they work for you!



  • Augusta Jamin added an answer in Agarose Gel:
    How do I get higher molecular weight band after PCR clean up followed by gel extraction of double digested inserts?

    It's confusing to find extra bands of higher molecular weight in my insert sample which was PCR purified by gel extraction method. The insert bands were very clean in 0.8% agarose gel. It was followed by double digestion with NheI and HindIII enzymes at 37 degree overnight. During the second round of gel extraction after digestion, I found two bands-one equivalent to my insert size and another band higher than my insert.

    Can anyone has suffered the same problem? Please give your inputs.


    Augusta Jamin · University of Nebraska at Lincoln

    Hi Gaurav,

    I am not sure what you meant by 'high' detectable amount, is it to a comparable level as your insert? Using agarose gel, you can detect at the minimal ~10 ng of DNA. So if there is contamination around such amount of DNA, it can be detectable. You may also test other components of your digestion mix, for example the water or buffer components that you use that may possibly be the source of DNA contamination. Maybe try fresh water or a different batch of buffer. Also may be use a different box of pipette tips. 

  • Kaushik Mukherjee added an answer in FRP:
    How do we model FRP orthotropic material in ANSYS?

    Element types & input parameters, and concrete FRP interface modelling..?

    Kaushik Mukherjee · IIT Kharagpur

    Dear Gayan Wijesundara,

    In ansys the element types and material property are normally two independent entity. In order to model FRP orthotropic material, I would suggest the following things (assuming that you are trying to analyse a 3D model):

    1) element type: 10 node quadrilateral

    2) material type: select orthotropic material property, instead of isotropic one, and define all the required elastic constants.

    Best regards,


  • Andrew Rael added an answer in Nucleic Acid Isolation:
    Why does my mixture pass through filter prior to centrifuging during DNA extraction?

    Hi everyone,

    I'm now working on DNA and RNA extraction for FFPE samples using "RecoverAll™ Total Nucleic Acid Isolation Kit for FFPE" (Life Technologies).

     After digestion by Proteinase K (usually incubate more than 24-48hours until all samples were transparent), I followed the manufacturer's protocol: I added mixture of Isolation additive, Ethanol with Digestion products and pippetted the mixture on the Filter. As normal, the mixture will not pass through the filter. However, some of tubes the mixture passed through the Filter (about 50-100 mcL) prior to centrifuging.

    Can anyone explain why this phenomenon happen and how to solve it?

    Thanks a lot

    Andrew Rael · IntelliCyt

    I have used up to 10% Proteinase K (20 µL per 200 µL reaction) in digestion of fresh or frozen tissues. Generally these were incubated overnight at 55° C. What temperature are you incubating at?

  • Carlos A. Luengo added an answer in MWCNT:
    What dielectric constant of individual multi walled nanotube at low frequency?

    dielectric constant of individual multi walled carbon nanotube at low frequency?which section of permittivity of MWCNT is stand for dielectric constant of MWCNT imaginary part or real part?

    Carlos A. Luengo · University of Campinas

     I agree with Dr Hugh J Byrne.

  • Ariane Álvarez Álvarez added an answer in Higher Education:
    Do you know studies about indicators measuring the applied research and technology transfer in higher education institutions?

    I am part of a group of researchers who want to set indicators to adopt in Portugal.

    Ariane Álvarez Álvarez · Instituto Superior Politécnico José Antonio Echeverría

    CDE. Manual de Frascati: propuesta de norma práctica para encuestas de investigación y desarrollo experimental. París: OCDE, 1993.
    Oslo Manual: proposed guidelines for collecting and interpreting technological innovation data. París: OCDE, 1997.


  • Michael Löhr added an answer in Nursing Staff:
    Does anyone know how to measure the number of nursing staff in inpatient Psychiatry in UK and Norway?

    In Germany, we just generate a new funding system for inpatient Psychiatry. I am grateful for any advice.

    Michael Löhr · Fachhochschule der Diakonie gem. GmbH

    Dear Marit,

    thank you very much for this informations.


  • Sofiane Saouane added an answer in Raman Spectroscopy:
    Is it possible to remove Raman background signal ?

    Trying to obtain characteristic Raman signal from semi pure samples, however, the background signal from 1000-2000 cm-1 was always very strong, and this might overlap some useful signal response. 

    Raman spectrometer used in this study is the Perkin-Elmer Raman spectroscopy, which employed a diode laser operating system at 785 nm with average power of 100mW at the sample and 100-micron spot size.

    I obtained the signal by transferring power samples onto glass slides under microscopy (20X). 

    This strong background signal also appeared in another SERS experiment employing nanofilm deposit onto glass slide performed on this instrument. Silver nanofilm substrate was deposit on glass slide and placed on same glass slide. 

    BG from bare glass slide ( without anything on it) 


    BG from SERS substrate ( with As III droplet on it )


    Question. what is the source of this background signal ( 1000-2000 cm-1), and how to eliminate it? 

    Thanks for your help and input!

    Sofiane Saouane · Georg-August-Universität Göttingen

    Hi Weiming,  

    It seems that your glass slide is fluorescent in that region with the 785 nm laser. Please find below a similar thread discussing the same issue. 

    One option that I would try is to change completely the glass slide and try something pure like silicon or diamond as a "glass slide". There are most likely other materials emitting few peaks too I dont recall which ones. I'm personally familiar with diamond anvil cells, so the bg that I get is one strong peak around 1350 cm-1.

    So if background substraction, filters, and trying another wavelength do not do the trick, try what I suggested, and please keep us posted of the result. 

  • Imre Tóth added an answer in 31P MRS:
    What kinds of information can 31 P NMR give me?


    I would appreciate if you could guide me about 31P solid states NMR analysis. I want to measure the P adsorption on calcite crystal (I add P as additive to the crystals precipitation solution and see surface modification).

    What kinds of information solid states NMR can give me? I mean,

    can it tell me binding between P-Ca and strength of the bond?

    amount of P adsorbed?

    configuration of P on the surface

    or it just will tell me there is P or there is not. 

    Can it say P is on the surface or it has incorporated to the crystal structure


    Imre Tóth · University of Pannonia, Veszprém

    Most of your question is already answered by Raeesh above. In your case I suggest that you should also take a 31P NMR spectrum of your P-additive alone in solution. When you see significant difference in the 31P NMR chemical shifts of the additive in solution and the treated calcite by CP-MAS 31P NMR then you can assume some kind of interaction or bond between calcite and P, otherwise you have only adsorption. Solid state 31P NMR can also indicate whether multiple species are formed. You didn't disclosed the kind of P-additive you used unabeling us to answer whether P-Ca bond formation is possible.

  • Urie Bezuidenhout added an answer in Eye-Tracker:
    Does anyone have any tips for MiraMetrix S2 Eye Tracker?

    Hello, my lab purchased this model some time ago, and it has been extremely problematic.  It frequently loses track of gaze, and only works by trial and error when lighting in the small testing chamber is custom-adjusted for each subject, and even then the session is marred by frequent errors. 

    The company has been unhelpful, and has suggested obvious things like changing lighting and distance, which have been tried to no avail.  They also put our RAs through hoops of shooting and furnishing videos of it misbehaving, yet has essentially insisted that problems are all due to operator error, and has indicated that we are left to our own devices.

    Does anyone have any internal lab guide for use and setup of this model to get it to work reliably?

    Urie Bezuidenhout · University of Auckland

    Hi I use one as well, and have had other types of problems particularly with recording and playing dynamic gaze trails with video. I have used mine for a number of months ( some time ago now) and found diffculty with  users with spectacles generally which are very problematic to calibrate and maintain tracking during a session.  

    I also found that backlight spill from another source makes it tricky to record, so maybe just use a single light source in your lab.

  • Olga Lock added an answer in Separation:
    How to fractionate the most promising individual compounds from the crude extracts?

    I want to know the easiest and least expensive compound fractionation or separation methods and its most commonly used techniques to ascertain the in vitro activity of the separated compounds

    Olga Lock · Pontifical Catholic University of Peru

    You didn't say which is your raw material, I suppose is a plant. As you know plants have hundreds of compounds and they are classified as primary and secondary metabolites. For the last one we use liquid- liquid partition and majorly chromatographic techniques ( TLC, CC, GC, HPLC, electrophoresis and so on). Do you want to separate or isolate a special kind of secondary metabolites? Some times you can get a particular methods. Please, be more explicitly. 

  • Kara Doriani asked a question in School Leadership:
    What are good ways to locate and recruit the best school directors to interview them for a qualitative research study? (Setting: Santiago de Chile).

    In developing a new technology for the training of school leadership in Latin America, we are seeking to learn about the experiences of "expert" school principals so as to pass on their knowledge through this technology. As such, we want to utilize the most time and cost-effective ways to get in touch with these people, especially in terms of how  you would determine their level of expertise in a qualitative research setting. Thank you all for your thoughts!

  • Gonçalo Paiva Dias asked a question in Graph Drawing:
    Can you recomend any software for quickly build sociograms?

    A sociogram is a graphic representation of social links that a person has. It is a graph drawing that plots the structure of interpersonal relations in a group situation.

  • Jason Chang asked a question in Aquaculture:
    Can the combination of "Microbes" in fertilizer/feed/water treatment the new trend for the both the agriculatural and aquaculture marketplace?

    Several companies have come to development with product solutions with microbes but the average amount of microbes is less than 5%.
    We have found a process to increase that number to almost 30%, adding not thousands but billions of microbes.

  • Mahboubi Chikh Younes added an answer in Bioturbation:
    Please can you help me to know about this bioturbation which I found it in lower callovien of algeria?

    please can you help me to know about this bioturbation which I found it in lower callovien of algeria

    Mahboubi Chikh Younes · University of Oran

    Dear Johannes Kalbe 

    That you for your answer. The informations was very beneficial for me , I think that maybe it could be an echinoid socilia but I can't found echinoides on this banc. We have an ammonites level what make me confused.

  • Peter G Hains added an answer in LC-MS/MS:
    How do I analyze LC-MS/MS data for a with label free approach using progenesis QI software?

    I am searching for a reference article which uses  LC-MS/MS analysis to make Quantification with label free approach using Progenesis QI software. I have two set of protein profile with control and treated with a target compound, this results are obtain through LC-MS/MS analysis followed with label free approach using Progenesis QI software.

    if there any related research article to take as reference while writing a article ?

  • Rob Schlingman added an answer in Mechanical Design:
    I am using a universal joint for connecting two shafts at an angle. As this angle keeps on changing, what is maximum degree of performance of joint?

    The universal joint is normally used in machines where angle between two shafts is low. Is there any study available about change in performance of the joint as the degree increases. What is maximum limit of angle up to which a universal joint can perform? Please supply me the references.

    Rob Schlingman · Pacific Research Laboratories, Inc.

    Most engineering handbooks (e.g., Marks’) will state that shaft angles up to 30 degrees can be used with a Hooke’s-type joint (aka Cardan joint). Remember, this is a non-constant velocity joint, and the greater the angle, the greater the rotational speed variation, vibration, and wear.

    At 15 degrees, the angular velocity ratios are Ωmax 1.0353 / Ωmin 0.9659. At 30 degrees, Ωmax 1.1547 / Ωmin 0.8660.

    Take your input RPM times those factors to determine the max and min angular velocity on the output shaft. Expect the coupling life to be half at 30 degrees. The optimal configuration is dual couplings with an intermediate shaft, and all of this becomes moot.

  • Ehsan Ziyaei added an answer in Polarization:
    Why do most of the peoples perfor potentiodynamic polarization measurements at scan rate of 2mV/sec?


    Ehsan Ziyaei · Isfahan University of Technology

    Hi, i think you should check this article:


  • Elsie Amedonu asked a question in Ion Channels:
    What is/are the probable role of potassium-ion channels for the differentiation of T-lymphocytes in multiple sclerosis?

    mechanism of action and ion channel blockers involved

  • Edwin A. Locke added an answer in Causality:
    Is a concept of causality required in science?

    John D. Norton characterized "Causation as Folk Science",

    (see http://quod.lib.umich.edu/p/phimp/3521354.0003.004/1).

    Would you say that causality is a well-defined concept that is

    essentially required in science?

    Edwin A. Locke · University of Maryland, College Park

    well this argument could go on for a long time. But my essential point is that there is nothing random metaphysically--this would mean that entities have no identity. Randomness is an epistemological concept based on the fact that we lack some knowledge (e.g., I did not know I would meet my future wife at that bookstore). If modern physics believes in random metaphysical events then I disagree with modern physics. The possibility of multiple causes does not have to be part of the definition. The law of causality is simply the law of identity applied to action.  Causes are never events as such; there has to be something that acts, an existent. The cause of a billiard ball moving is not another movement but another billiard ball moving. Disembodies motions are not motions of anything--that would be mystical

  • Albert Manfredi added an answer in Stream Ciphering:
    Can we consider bent function in the design of new encryption algorithm ?

    Bent functions are used in the design of (1) block cipher cast 128/256, (2) Stream cipher Grain, and (3) Hash function HAVAL. Bent functions allows to have near-perfect diffusion but suffers from balance. Since bent function is not balanced, correlation attack is a problem. 

    Should we consider bent functions for new algorithm development ?

    Albert Manfredi · The Boeing Company

    Your question has been on my mind. In short, what extra conditions do you need to place on bent functions, in order to allow their use in pseudo  random number generation for cryptography?

    Did you run across this paper?


    In Section 2.3, the authors address the issue of bent functions and whether they can be balanced. Their Theorem 1 appears to be what you are looking for.

    Their answer to your question is a qualified "yes." They offer three models, and the first model, with restrictions as described, creates pseudo random numbers that pass all of their tests. The other two models are not so fortunate.