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  • Lepelletier Yves added an answer in Quantification:
    Which method should be used to quantitate endothelial tube formation?

    In one of the experiments using an endothelial tube formation assay, I can see a very clear difference in that the treated vs control group showed differential tube formation in terms of number, thickness, size etc.

    Now, I would like to have that data in the form of numbers so they can be plotted on a scale.

    Any ideas or methods that help me in quantification of tube numbers, size, thickness etc, or overall tube formation would be helpful.


    Lepelletier Yves · Institut Imagine - Université René Descartes - Hôpital Necker

    dear, i'm agree with carol, unfortunetly it's money and time consuming process using Metamorph software. i've recently discover a new informatic platform that allow rapid analysis with multiparameter results (tube length, cell area, nets, tube size....). 5 minutes analysis is needed to receive results, you just sent your picture in the plateform. it's not realy expensive, and before to buy analysis you can analyze 10 pictures for free. before, i've used Metamorph or Image-J, now i prefer this analysis process from IBIDI compagny (Wimasis image analysis platform ).

    best regards

  • Robert Yaffee added an answer in Cointegration:
    How many cointegration is possible in applying cointegration Johansen test?

    Dear All,
    I have applied the Johansen Cointegration to test the long relationship between variables, I have found 5 cointegration for my model according to Trace and Max-Eigen statistics. I wonder how many cointegration is possible to have ?
    I have found some Articles having 6 cointegration and other having 3 or 2?
    I have confused which number is best to have it in your model ? Having high number of your cointegration does it impact you model?
    Please could I have some advices?

    Robert Yaffee · New York University


         The answer may depend on the kind of cointegration you have.  If you have an I(2) cointegrated model, you may not be able to restrict yourself to the long-run impact matrix of reduced rank to determine the number of cointegrating vectors you have. Also, if you have a multicointegrated model, this matter may be more complicated than you would think.

          You might also have seasonal or periodic cointegration, which would provide additional considerations to answer this question.

         If we assume that you are only referring to I(1) cointegration, then the answer is simpler:  The number of cointegrating vectors in the I(1) case  depends on the results from either the  Johansen trace and/or maximum eigenvalue test.  But that test will depend don the number of autoregressive lags that you include in your model.   According to Luktepohl, that can be determined from a vector autoregression model using information criteria -- the HQ or BIC are the preferred ones.  


               Bob Yaffee

  • D. Prasath added an answer in Field Crops:
    Are field crops resulting from the treatment of seeds with gamma irradiation before planting safe?

    What are the rates of safety?

    D. Prasath · Indian Institute of Spices Research

    Yes, I agree with Ranjith... nice reply. We too have same experience in vegetatively propagated crops.

  • How shall i know if the impact factor of a certain journal is true or fake?

    I would like to make sure that the impact factor of any journal is true not fake

    Salah Eldeen Gasim · Sudan University of Science and Technology

    The best way is to use the JCR as Dr. Mohammad stated. I found it more accurate as compared to other sites.

  • Do you prefer blind review process of your research paper?

    Some journals get their research reviewed after hiding the names of the authors. What is your preference and why? What is the fair review process: blind or open

    Lepelletier Yves · Institut Imagine - Université René Descartes - Hôpital Necker

    I can dream. As reviewer, i prefer to know who want to publish an article to verify if this work or a part of it, is not already published by this same team, sometime authors are not so fair but i never put in consideration authors reputation. up to me, it would be better if reviewer have the name author access and also accept the publication of their critics with their name. that's the main fair process. as author, i want to know who has reviewed my article (to verify if no conflict of interest exist), and as reviewer, i want to have my critic published (to reinforce serious reviewing).

  • How do human resources managers' perceive their role in addressing and deterring workplace bullying?
    As above.
    Mary Jane Burnett · Walden University

    Dr. Arhan Sthapit,

    I had to change my topic for my dissertation so I can get through the process. I plan to study workplace bullying after I become Dr. Burnett. 

    Thank you for taking the time to answer my questions and provide your study.


    Mary Jane

  • Purva Sanganeria added an answer in Alginate:
    Can anyone help me to interpret my SEM picture. I encapsulate msc for 21 days in a scaffold. Do these pictures show differentiated MSC??

    I encapsulated MSC in alginate beads.

    Purva Sanganeria · Narsee Monjee Institute of Management Studies


    First of all, which differentiation you are observing here, as oil droplests of adipocytes can not be analysed by SEm at all ? I can still think of osteo and chondro ?

    For determining the differentiation of your MSCs, electron microscopy alone that too only for the 21st day is not the enough and also not the right choice ?

    Either do a SEM analysis of your differentiating cells at all the Time points and analysex the morphological variations in terms of calcium deposition in osteocytes and proteoglycan deposition in chondrocytes. Moreover, just morphology evaluation will not be a confirmation therefore try the elemental analysis using some standard which is normally used for Calcium, Proteoglycans, alginate and whatever your scaffold is made off !!

    I hope this can be of help to you !

    Analyses of your alginate beads alone will also help you to dicriminiate among the cellular morphology and bead morphology separately.


  • What are extensive classifications/taxonomies of learning tasks (ideally for Physics)?

    Hello together, I'm working now at an adaptive system for Physics and I'm going to divide physic exercises into tree categories: with low, middle and high complexity grade. The one dimension which we apply is the task/learning objective classification of Andersson but this dimension dosen’t convey all task characteristics we need like e.g. number of used formulas, number of physic concepts or decision steps. I would be very happy if somebody suggested to me any extensive classifications/taxonomies of learning tasks (ideally for Physics) that address this problem. I Thank you in advance. Best regards.

    Alicia Montecinos · Pontificia Universidad Católica de Valparaíso

    I have been listening a lot about Marzano & kendall's taxonomy. You may want to check it out.

  • Anantha Kumar Muthusamy asked a question in Fireflies:
    How the firefly algorithm can be related with Wind Energy applications?

    I am planning to use firefly algorithm in extracting the maximum power at wind  applications. How it can be related?

  • James R Knaub added an answer in Survey Methods:
    Is there an online software on how to choose sample in survey method?

    I am going to work on survey method but here I need one software for choosing sample for field work.

    James R Knaub · Energy Information Administration

    You are asking about sampling from a finite population, about which you wish to estimate statistics such as totals, or means, correct?

    There are, as has been noted, many sample designs, and your sample size will be partly determined by that, and partly determined by innate variance, how accurate you want your answers to be, and often greatly muddled by nonsampling error, including measurement error. Generally, once you have decided on a design, and obtained some information (enough for good 'guesses') on variance, a calculator or formula for a sample size estimate will give you an estimated sample size that actually assumes no measurement error or other nonsampling error. But if you try to use a sample size that is too large for your resources, you may do much worse than expected, because of the nonsampling error.

    Also note that your estimation method has to be consistent with your design. If you use regression (model-based) estimation, then the design is not so critical, though you always need to stratify properly so that the data modeled together belong together.

    Note that there are probability-based methodologies (often called "design-based"), model-based methodologies, and model-assisted design-based methodologies. The advantage of modeling (which requires auxiliary/regressor data on the entire population, where perhaps administrative data will do) is that a random (probability) design can, by bad fortune, give you a sample that could be said to not be 'representative' in that estimations of population totals based on that sample alone would not be very good.

    A good book, perhaps relatively easy to obtain, to consult for random design-based methods, would be Cochran, W.G.(1977), Sampling Techniques, 3rd ed., John Wiley & Sons. On pages 77 and 78 in that book, Cochran discusses estimation of sample size needs for a simple random sample. A sample size estimator analogous to this, but for a robust model-based estimator, is in the paper at the link below. Cochran has a great deal of good information in a small book, but is mostly on design-based methods. A good book on model-assisted design-based methods would be Särndal, C.-E., Swensson, B. and Wretman, J. (1992), Model Assisted Survey Sampling, Springer-Verlag. My paper, link attached, is the only method of which I am aware which estimates sample size needs from a finite population, based on a strictly model-based approach.

    There is also the problem in a survey, of determining sample size needs for more than one question on a survey. This can get rather muddled too. Often for a design-based survey, one is told to concentrate on doing well for just a few key questions. The two books noted above may have something on this, but an Internet search for articles is advisable, in addition. For the paper at the link attached, an iterative approach, looking at one question at a time, is advisable. The sample for one question will impact the sample needs for another.

    If you have a very simple problem, which seldom occurs, but perhaps it is sufficient for your purposes, say a simple random sample for one question, then pages 77 and 78 from the third edition of Cochran noted above, may be satisfactory. In that case, if you then need to choose the sample to go with it, any software with a random number generator might be used.

    Whatever software you use, you will want some expertise to be certain it is actually doing what you want. Stratification for any sampling method is often very important, but you will need to be able to tell the software how this should be set up.

    I think that SAS may have something to help in such simple sample selection, and I suppose other standard software packages do as well.

    If you are doing simple random sampling and want to find something online to help select the members of the sample, you will need to look for something with a random number generator.

    Note that you should also estimate variances for relative standard error estimates, or confidence intervals, for the aggregate results you report in the end.

  • Santanu Das added an answer in Handling:
    How can I combine AHP, linear programming and transportation algorithm into one single model that will be used in solving some supply network problem?

    I  want to develop a model that can combine all the three into just one model. The AHP will handle vendor selection, linear programming will handle the combination of raw materials at varying level of BOM while the transportation Algorithm will handle the distribution of the finished products to the consumer at a cost effective manner.

    Santanu Das · Kalyani Government Engineering College

    The answers given by the researchers above can be considered for implementation. References given also throw light on how to attack the problem.

  • Majid Jamshidy added an answer in Finance:
    What are the best guidelines for a finance company in underdeveloped countries?

    I would like to compare some under developed countries.

    Majid Jamshidy · Universiti Teknologi Malaysia

    please read attached files.


  • H. T. Basavarajappa added an answer in Upgradation:
    How can one separate or upgrade illite from a composite?

    I have a composite of kaolinite(80%) and illite(20%), is there any method to separate or upgrade the illite from this composite? Please give me a detailed method which I can follow in labl. Thanks a lot

    H. T. Basavarajappa · University of Mysore

    You can separate any mineral by using I so dynamic separator instrument other than that you can go for mineral separation by the binocular microscope you can pick the mineral grains

  • Alvin Vista added an answer in Regression Modeling:
    How can I transform beta coefficients to standard deviations?

    If beta coefficients are available from a regression model, how can I extract the standard deviation and mean of the initially inserted data into the regression model?

    Alvin Vista · University of Melbourne

    the beta coefficients are simply standardised versions of the regression coefficients. in turn, regression coefficients represent the 'slope' of a particular variable (the predictor) with respect to the outcome variable. if you only have either the regression coefficients or its standardised form and nothing else, you won't have enough information to compute the mean or standard deviation of the predictor or outcome variables.

  • What are the differences between Marklund and Marklund method (1974) and McCord and Fridovich method (1969) to determining the SOD activity ?

    Hello everyone. I want to determine superoxide dismutase (SOD) enzyme activity in the greater wax moth, Galleria mellonella, hemolymph. However, there are so different methods such as Marklund&Marklund method, and McCord&Fridovich method. İn Marklund method, they used ''pyrogallol'' while McCord's method used ''xanthine'' and ''xanthine oxidase''. Likewise, in marklund method is determining at 440 nm, but, Fridovich method is determining at 560 nm. Which method is better to determine SOD activity and what is the basic difference between them? Thank you.

    Frank Hernández Rosales · Centro Integral de Salud . Santiago. Chile

     I am using in hemolyzed erythrocytes  the method described by Marklund & Marklund  with satisfactory results. I found this method is easier then McCord and Fridovich method.

  • Do you use movies in teaching?

    The use of movies provides educators with a valuable tool and means a break to traditional teaching methods.

    What do you think about that? Have you ever used movies as a teaching tool? Please, tell us about your opinion and your experiences.

    Krishnan Umachandran · Professor

    I have made my students to  submit their assignments online through YouTube. Instead of having professional videos, the students made PPT converted into video files are well accepted and debated among the students. I feel this is more collaborative, involved, participatory and peer evaluative learning.

  • Vijaya Krushna Varma asked a question in Corruption:
    Can you evaluate my suggested electoral and political reforms which are aimed at removing corruption at all levels and in all forms?

    I am suggesting electoral and political reforms to remove corruption  at all levels and in all forms and to usher in 100% transparency in governance and administration. Can you evaluate my prescribed reforms?

  • What is the impact of the demographic change on our democracies?

    Demographic change is a well-studied phenomenon in most societies. Its impact on social systems and economy has been discussed for some years - mainly with a focus on ageing. We just finished a project on demographic change in South East Europe with policy scenarios. But what does demographic change mean for democratic legitimacy, voting behaviour, political rights, citizenship etc.?

    Peter Woolstencroft · University of Waterloo

    Electoral participation, generally, is falling, with most of the change occurring in younger cohorts. As the electorate ages, both because people are living longer and older people have higher participation rates than do younger people, one would expect that parties would be more oriented to older people and they, in turn, may be more conservative in the sense of being unwilling to respond to "new" political perspectives.

  • which Software is best for an Antenna Design?

    Antenna design Software

  • yi Yan added an answer in Photonic Crystal Fibers:
    How could I apply a uniform magnetic field perpendicular to photonic crystal fiber by using COMSL?

    I need To apply a uniform magnetic field in perpendicular direction on photonic crystal fiber by using COMSOL multiphysics or any other software, I am already design a PCF with COMSOL.


    yi Yan · University of California, Los Angeles

    Dear Mr Dobre, as I mentioned in my previous reply, I used the way you described to add a uniform magnetic field in remanent magnetic flux density option but the issue is after running my module, the magnetic field from my result is not consistent with the value I added in the remanent magnetic flux density. For example, my applied B0 I used is 1T, which is the Br term in the remanent magnetic flux density, but the result after running gives me e-16 T which is way off. I guess the explanation for this inconsistency will be either the Br is not added in the solver which turns out almost zero (e-16 T) in the result, or there should be a coefficient between Br I added in the remanent term with the real value in the solver (in this case for example, the coefficient will be e-16) 

    If you have any thought about that, please let me know. Any information or comments would be greatly appreciated. 

    Thank you

  • H. T. Basavarajappa added an answer in Earthquake:
    How to calculate the amplification factor of long-period ground motion in a deep basin?

    In Subduction zone where there are large Megathrust Earthquakes which have a lot of low-frequency energies. These low-frequency energies can travel very far because the wave-length is longer.

    For that reason, Megathrust earthquakes give an impact on some distant cities which are on the soft soil basins.

    Normally, the distant earthquakes will not have problem if there is not soft soil basin to amplify the long-period ground motion.

    So, what are the methods to calculate how much the deep basins can amplify the long-period ground motion? Or please suggest to me some documents to read.

    H. T. Basavarajappa · University of Mysore

    Better you do the

     3 D modelling   of the basin after you can use the above formula for  calculating the area 

  • Krishnan Umachandran added an answer in Health:
    Do you have national strategy for health in your country and if so how effective it is?

    National health strategy in different countries and its applications

    Krishnan Umachandran · Professor

    It is very effective throughout India, named as the Employees’ State Insurance Scheme of India, is a multidimensional social security system tailored to provide socio-economic protection to worker population and their dependants covered under the scheme. Besides full medical care for self and dependants, that is admissible from day one of insurable employment, the insured persons are also entitled to a variety of cash benefits in times of physical distress due to sickness, temporary or permanent disablement etc. resulting in loss of earning capacity, the confinement in respect of insured women, dependants of insured persons who die in industrial accidents or because of employment injury or occupational hazard are entitled to a monthly pension called the dependants benefit.

  • Do you think whether it is proper to connect gravity exclusively with the speed of light?

    Since the beginning of the twentieth century the speed of light is thought to be fundamental to gravitation and its transmission effectiveness. Mathematical physics seeks whether this idea is sufficient for explanation of all phenomena related to mass attraction. Is a change of position needed? What is your opinion?

    M.A. Padmanabha Rao · Defence Laboratory, Jodhpur, Rajasthan, India

    Gilbert Rooke, I reproduce my comment made  earlier on the topic 'Sun’s role in warming the planet may be overestimated, study finds' http://www.bnbtimes.com/general/suns-role-warming-planet-overestimated-study-finds/

    Rise in gravitational force, if any, during the period of observation also can attract high energy radiations both ionizing (including gamma, X-ray, and beta) and non ionizing radiation like EUV or UV. How gravitational force acts on radiation and matter is explained in the following. In physics, some missing gaps still exist. My experimental and subatomic research with radioisotopes and XRF sources has revealed that beta does not exhibit its well known particle behavior within an excited atom of a radioisotope or X-ray source. I believe when beta escapes from an excited atom, beta acquires mass due to Earth's gravitational attraction. It is because gravitational force shows attraction on both matter and radiation. For example, abundant cosmic radiation from Sun such as gamma, X-ray, beta, as well as EUV at North and South poles are due to attraction by Earth’s high gravitational force. In tropical countries such as India relatively less energetic radiations including visible light and infra red radiation from Sun are due to Earth’s relatively low gravitational force. All such examples lead to an entirely new concept that both matter (such as electrons, protons, neutrons) and radiation (conceptually both photons and waves) consist of three components: (a) electric, (b) magnetic, and (c) gravitational forces. In a particular situation only one component is in excess, so influences accordingly on electron or photon. This needs a detailed explanation.

  • Paul Louangrath added an answer in Stock Markets:
    How can I find the daily figures of CNN fear and greed index for different countries?

    To lanyse the interaction between stock markets and thsi index, the figures are needed.

    Paul Louangrath · Bangkok University

    ISSUE: Greed & Fear Index for stock markets in multiple countries.

    GREED AND FEAR INDEX: CNN uses 7 factors and each factor is weighted to calculated the weight average of what it defines as greed and fear on a scale between 0 - 100. These factors include:

    -Market momentum
    -Market volatility
    -Put & call options
    -Stock price breadth
    -Stock price strength
    -Junk bond demand

    These indicators may not be tracked in all markets throughout the world. Even if they are tracked, the data may not be easily obtained. What is easily obtained is the main indices for the market, i.e. composite indices.

    WORLD INDICES: One can construct a cross market comparison or a global market index by using the main markets of the world to make one "global composite." For example, select 10 international markets and track their movements; give each market appropriate weight. They do not have to be equally weighted since each market has different size. One can give weight according to volume or amount of dollars in market size, for instance.


    From these 10 markets, a single Global INDEX may be constructed. The next step is to define "greed" and "fear." There are two ways of doing it: (i) define greed as p and fear as q in a discrete probability fashion, or (ii) construct two parallel indices one called Greed Index and another called Fear Index; both from the same markets but each category with different indicators, i.e. tracking movement between stock and bonds.

    FIGURES & DATA: Following the above suggestions, historical data from each major market in the world are available and easily accessible. To follow the CNN 7-factors index, however, there is no equivalent data to what CNN tracks.

    POSSIBLE APPROACH: The use of index is to have an indicator to track the movement of the market through time, i.e. daily, weekly, etc. Assume that the measurement of the movement is in a form of market elasticity. Let Q = volume of shares traded; and P = amount of money changed hand, in each market; then the elasticity is simply:

    (1)   Em = [(Q1 - Q0) / Q0] / [(P1 - P0) / P0]

    ... where m = market, say m1, m2, ... m10. Now, each market is of different size, let's weight each market according to size. Em now becomes Em(w). Call this Em(w) an estimated function for each market movement.  Next used Kahneman-Tversky prospect theory's utility function to determine the U-index. The original U-equation is given by:

    (2)   Ui = sum(piwivi)

    ... where p = probability of each i; w = weight of each category; and v = predicting function. in this above proposed case wivi = Em(w). Then Ui is simply:

    (3)   Uiw = sum(piEm(w))

    The next step is to defined "fear" and "greed." In a rudimentary manner at this point, we can defined greed and fear in a discrete probability form. Assume that p = greed and q = fear in binomial categorical data. For an increase or movement in positive direction, capture it as 1 and 0 in the opposite direction. Since p + q = 1, the index could simple run from 0 to 1. In a more developed fashion, we can expand the E term to include many factors.

    [1] Kahneman, Daniel, and Amos Tversky. "Rational Choice and the Framing of Decisions." The Journal of Business 2nd ser. 59.4 (1986): 251–78.
    [2] Kahneman, Daniel. Thinking, fast and slow. Farrar, Straus and Giroux, 2011. (p317).
    [3] Kenney, J. F. and Keeping, E. S. Mathematics of Statistics, Pt. 1, 3rd ed. Princeton, NJ: Van Nostrand, p. 66, 1962.

  • Any suggestion on mixing nano power material in diesel fuel?

     I am doing research in IC engine. Nano fuel additives is readily available in markets. but I wish to know the procedure of mixing nano power material with diesel fuel.

    Maddali V S Murali Krishna · Chaitanya Bharathi Institute of Technology

    Once the combustion is improved with the blending of nano particles with the fuel, there may not be problems related to PM but it may increase the oxides of nitrogen as gas temparatures  will increase. However, as Dr. Sridhar V, said, PM may increase with the increase of density of fuel as density is related to PM. Hence it is difficult to predict at this stage, unless experimentation is carried out. Hence work in this direction is appreciated and worthy.   

  • Chao Wang asked a question in GIS Mapping:
    Who can tell me where can I download the ArcGIS map of Global soil carbon content and Soil respiration?

    Hi all, i am working on a project that needs two GIS maps of Global soil carbon content and Global soil Respiration. So, who can offer me a website or some ftp sites that i can get those maps. Thanks

  • Will it be a relevant study if I associate only the level of blood pressure with physical activity status?

    I have already collected data in context to identify the prevalence of risk factors of non-communicable diseases in a particular region by applying WHO's STEP 2 approach. so I dont have boichemical data in hand.

    Kishor Adhikari · National Medical College, Birgunj, Nepal

    Thank you Dr Leischik your attachment was worthy

  • Ilja Schmelzer added an answer in Gravity:
    Is the bending of light locally related to the equivalence principle?

    The equivalence principle is locally applied in GR. At the same time light is bent due to gravity, I just want to know is there a relation between them locally?

    Ilja Schmelzer · Independent Researcher

    Robert, what I'm saying is that the Einstein Equivalence Principle (EEP) is fulfilled in all metric theories of gravity.  (The Strong Equivalence Principle not, it is stronger.) So, what can be derived from the EEP does not go beyond the properties shared by all metric theories of gravity.  

    Among the metric theories of gravity will be, of course, acceptable ones (which agree with observations) as well as unacceptable ones (which disagree). But acceptable or not is irrelevant if the question is derived from EEP or not. If there are two metric theories of gravity, thus, two theories where the EEP holds, and they predict different values for light bending, then light bending cannot be derived from EEP alone.  Point.  That at least one of the two - because it predicts a wrong value for light bending - has to be false is completely irrelevant if the question is if the light bending can be derived from EEP or not.  In this case, even a wrong theory can give a counterexample. 

  • How do you calculate the cumulative drug release in percentage?

    I have the absorbance data as well as the corresponding concentration values at different interval for drug release study. Please help me to get the percentage of cumulative drug release at different times

    Aneeya Kumar Samantara · Institute of Minerals and Materials Technology

    Thanks Nooshin,

    But I have already calculated the concentration of drug that has been released. But I am facing difficulty to find out the percentage of cumulative drug release at each time interval.