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  • Hamidreza Farhidzadeh added an answer in Texture:
    Does gray level co-occureence matrix require after 2D-Discrete wavlet transform to extract texture features of scanned currency image?

    I want to extract features like roughness,homogenity,coarseness using dwt.But I found in some answers about using glcm after dwt.Does it need?Is it impossible to extracte such features directly by using dwt.Most research paper using dwt extracted mean,standard deviation, vertical component and horizontal component features only.

    Hamidreza Farhidzadeh

    No actually, I use it without any pre-processing. It works fine sometimes

  • Marianne Kjøller asked a question in RStudio:
    How to convert from INT to NUM in RStudio?


    Struggling with RStudio again, and now I have come across something rather odd. 

    My data is shown as "int" while data provided by RStudio is "num" (I attached a picture).

    Would this have any effect on my outcome when I do CA ordination plot and dendrograms? Because when I make these plots on my data, the dendrogram and ordination plot does not coincide, while they do it on R's dune data.

    In case it would, how do I convert my data from "int" to "num"?

    I've tried searching different place, and many seem to have the problem. I've tried using things like:
    "DF = as.matrix(as.data.frame(lapply(DF, as.numeric)))" but that makes my data as a list.

    and "as.numeric()" does not work either, as I get this error message:

    Error: (list) object cannot be coerced to type 'double'

    which I do not really understand...

    Thanks on behalf!

  • Adam Broinowski added an answer in Theatre:
    Can someone suggest me some good book or article about theatre and war and their relationship?

    I am currently writing a graduation thesis about theatre in war sites and I can't find a good book about this theme in theatre and in evolution. 

    Adam Broinowski

    If I may, I can suggest my book:

    Cultural Responses to Occupation in Japan: The Performing Body during and after the Cold War.https://www.amazon.com/Cultural-Responses-Occupation-Japan-Performing/dp/178093596X.

    The book looks at how artists responded to occupation in Japan that continues after the military occupation of Japan between 1945-1952. It shows how artists negotiated wartime memories as well as postwar 'peacetime' occupation during ongoing conflict and the militarisation of society, focusing on the body.

  • Avik Mondal asked a question in Microgels:
    How do I use alphaVbeta1 integrins to test my rgd functionlized PEG microgels?

    I've made 15-30 um sized PEGDA microgels that are functionalized with RGD (by incorporating  RGD-PEGA) into the mix. Effectively, the microgels are mostly PEGDA with some of the PEG strands containing RGD instead of acrylate at their ends. I'm trying to find a way using the alphaVbeta1 that I have access to in lab to test how well the RGD-PEGA got integrated into the microgels. For example, can I coat a coverslip with the integrin and see how many microgels get stuck to the slide?

  • Luis F. Gouveia added an answer in Auranofin:
    Hi guys how can i make a 10ug/30ul dilution from a stock of 20ug/1000ul ?

    I have a stock solution of auranofin 20ug/ml and i need to dilute further to 10ug but in a lower volume of 30ul any directives pls thanks

    Luis F. Gouveia

    An acceptable approach would be to pipette to the 1st well (or to each of the 1st row of wells) 30uL of the stock solution and then pipette 30 uL of the solvent. Homogenize the mixture by aspiring/dispensing several times. Now you have 60uL of a 10ug/mL solution in the 1st one.

    To the 2nd well (or 2nd row of wells) pipette 30 uL from the 1st well and then pipette 30 uL of the solvent. Homogenize the mixture by aspiring/dispensing several times. Now you have 60uL of a 5ug/mL solution in the 2nd one.

    To the 3rd well (or 3rd row of wells) pipette 30 uL from the 2nd well and then pipette 30 uL of the solvent. Homogenize the mixture by aspiring/dispensing several times. Now you have 60uL of a 2.5ug/mL solution in the 3rd one.



    To the 7th well (or 7th row of wells) pipette 30 uL from the 6th well and then pipette 30 uL of the solvent. Homogenize the mixture by aspiring/dispensing several times. Now you have 60uL of a 0.15625 ug/mL solution in the 7th one.

    Finally remove 30uL from the 7th well and discard them.

    You end up with 30uL in each of the 7 wells with the following concentrations: 10, 5, 2.5, 1.25, 0.625, 0.3125, 0.1565 ug/mL.

    You should be aware that this procedure is very practical from the experimental standpoint but suffers from the fact that the concentrations are not independent (the 7th solution is obtained by diluting the 6th one which in turn is obtained by diluting the 5th one which...) which requires proper statistical analysis. Any error in obtaining any intermediate solution will propagate to the subsequent ones. Proper care (read extra care) should be taken.

    Hope it helps (if so, please upvote)

  • Raffaele Sperandeo added an answer in Evolutionary Theory:
    It is conceivable evolutionary theory of rationality?

    Since the dawn of time, humankind’s singular ability to make decisions has allowed human beings to face innumerable environmental challenges and complex evolutionary dynamics. Environmental pressures are not so urgent anymore, comparing to our ancestors. Nonetheless, the number of decisions that contem- porary humans are called to make is very high. During the last three centuries, the change from normative to descriptive theories, from formal to natural logic, from substantive to limited rationality has allowed us to explain how many of the decisional strategies are coherent with the functioning of the cognitive economy of our species, even if they are limited and fallible.

    Raffaele Sperandeo

    I think another important issue is the decision in conditions of uncertainty and of risk. Theorists of decision making have for some decades been engaged in analysis of the logical-formal process of choosing in the presence of incom- plete information and in conditions of risk or of uncertainty. The formal theory of decision making was introduced in the first half of the twentieth century by Abraham Wald and was developed above all for use with Bayesian statistics which had as their objective the definition of the best strategy on the basis of a predetermined criterion of optimality. Over the course of time, various types of optimal results were identified for the analysis of decision making strategies: the choice which minimizes the maximum loss (which calculates for each choice the maximum loss that could derive from it, opting for the minimum one); the choice which maximizes the maximum gain (which calculates for each choice the maximum gain that could derive from it); the choice which tends towards the smallest average loss (according to the criterion of Bayes–Laplace); the choice which tends towards the smallest average loss (according to the criterion of Bayes–Bernoulli).

  • Paolo F Ricci added an answer in Poisson Distribution:
    Is the value of reliability constant during the year (period) or will decrease with passing time?

    Suppose that in a processor, the arrival of failures follows a Poisson distribution.
    Now, we encountered two different scenarios:
    1- We can define a constant reliability for it during a specific period. For example, a car that we say its reliability is 98 percent during one year.
    2- We define lambda (expected number of occurrences of failures in unit time t) for the processor. According to above example, can we calculate reliability for different months of the year?

    In other word, in scenario 1, the value of reliability is constant during the year (period) but in scenario 2 the value of reliability will decrease with passing time.
    Would you please tell me that which scenario is correct.

    Paolo F Ricci

    The answer to the question seems to require a mechanistic understanding of the problem at hand, rather than devising two scenarios and proceed probabilistically by assumptions. I am not sure what a processor means in your field. In my experience, built systems tend to degrade over time; as do most physiological systems. What matters is the window of time considered, not just the hypothetical year.One would seem to need specific information about the type of system (in series, parallel, whatever; maintenance, if any, and so on). Failure analysis deals with these using hazard functions and cumulative hazard functions. NASA has a number of publications that are extremely useful and free (www.hq.nasa.gov/office/codeq/doctree/fthb.pdf). Incidentally, some system actually harden for a certain period of time. hence, the two pronged scenario may be theoretically incorrect. Hope this helps a bit. There is much more to say on these matters. Finally, the Poisson assumption may not be appropriate as the distribution that may be appropriate can be that of the minima, maxima, Pareto, stretched Pareto and so on.

  • Chanchal Kumar Barman added an answer in Topological Insulators:
    How to distinguish surface states from bulk states in surface slab calculation?

    Hello Superiors,
    I have few questions related to Topological Insulators (TI). There are ab-initio surface band-structure calculation in TI. I liket to know answers on few of my following queries ......
    1.  What is the way to distinguish surface states from bulk states in surface slab calculation?
    2.  What is surface states (SSs) and Topological surface states (TSSs)? What is the way to distinguish them? Or how they are different ? Is there any tool to recognize TSSs and SSs?

    I will be delighted to have anykind of answers/guidelines from you people.

    Thanks & Regards

    Chanchal Kumar Barman

    Thanks a lot Francisco.

  • Stephen Joy added an answer in Psychotherapy:
    Does anybody know the Psychotherapy relationship questionnaire (Westen, 2000)?

    I'm looking for this clinician-report without results; please contact me if you have information about it

    Stephen Joy

    Here's a link to a PDF of the Bradley article; it includes the actual items, though it doesn't make clear the order of presentation. I agree with Adelheid that contacting Drew Westen directly is a good idea. The other link here is for his page at Emory and includes email, telephone, and surface mail info.

    + 1 more attachment

  • George Szynal added an answer in Kinect:
    Is there a tool for capturing 3D points inside buildings and their rooms?

    What we need is a pointer for picking spatial points inside buildings and their rooms, and 3D software which can convert those spatial data
    points into a 3D model.

    We want to pick floor and ceiling points for corners, and frames of windows and doors and hallways and wall-shape-transitions, etc. The idea is
    to save a ton of time taking and scribing measurements with conventional tools, and getting actual accurate shapes of rooms into the model very

    The model would be imported into Revit for further work, and remodeling to prep for visualization and walk-throughs.

    1. How can we get this done, and with what hardware and software?

    2. Perhaps finger tracking could work for this, and we would need to know who to contact for more information and possibly assistance

    3. This seems like a great R&D project if a system is not currently available. We can make resources available for QA testing at NMSU.

    We had considered that Kinect might be used, but expect it would not provide accuracy or be useful with a set of procedures that work the same
    in all rooms. We expect that something like an ultrasonic system with wand and reference unit would be useful and accurate for these purposes.

    Thank You for any assistance you may provide, and for taking the time to respond.

    George Szynal

    George Szynal

    Very useful responses. Thank you.

  • Martha Pantoja added an answer in Economic Development:
    Why do so many developing countries fail to transfer technology?
    Many countries in the southern hemisphere - from the Middle East to South America - have failed in their attempts to master the process of technology transfer. Significant efforts have been made without avail. Astronomical resources have been spent. In your views, what are the reasons for such failure?
    Martha Pantoja

    Investment in technology in developing countries is low.

  • Murray Ian Dawson added an answer in Plant Breeding:
    What is the defineition of plant sterility (infertile), and what is classed as low fertility?

    I ask this because we are breeding very low fertility or sterility in some cases to ornamental plants that are often classed as weeds. Some plants we have breed have been totally sterile for 5 years, then when they are much older, we have found some may produce 5 or 10 seeds on a plant. Then after we collect 100 seeds of 5 or 10 plants only 1 or 2 may germinate. I would class that as being safe and non invasive. Are there terms that can be used to explain such low fertility that will put peoples minds at ease.

    Murray Ian Dawson

    I see that the full Oregon Department of Agriculture and Oregon State University testing criteria for sterile or low fertility Buddleja is at https://www.oregon.gov/ODA/shared/Documents/Publications/NurseryChristmasTree/BuddlejaScreening.pdf. They state "produces less than 2% viable seeds compared to fertile cultivars that were evaluated under the same conditions and location" and provide the conditions under which this is tested.

  • Sebastian Schmitt added an answer in Reverse Transcription PCR:
    To design a Histidine tag on a forward primer, does it necessary that i have to add a linker in between the His tag and primer sequence?

    I am using the primer for Reverse transcription PCR.

    PCR products will be visualised on EtBr stained agarose gel.

  • Daniel Ibarra Marinas added an answer in North Africa:
    Dams database in the Maghreb (Algeria, Morocco, Tunisia) ?


    I want a complete database on dams in North Africa (Morroco, Algeria, Tunisia).
    I have already collected a databases "GRanD" and "AQUASTAT" , but they only contain large dams. I want to complete my database by small dams.

    Thank you in advance if you have ideas to find these small dams.

    Daniel Ibarra Marinas

    Global database of dams (but I´m not sure that it includes small dams):


    UNEP GEOdata from United Nations Environment Programme:


  • Yoshinori Shiozawa added an answer in Managerial Economics:
    What is the difference between managerial economics and economics of industrial organization?
    I am preparing a course in Managerial Economics. In general, it is required for graduate programs in Business and Economics. It is taught in some undergraduate programs as well. On the other hand, a separate course in Economics of Industrial Organization (or Industrial Economcis) is taught. These subjects have many topics in common. What do you think is the main difference between them? What textbooks could you recommend for both? Thank you!
    Yoshinori Shiozawa

    Dear John,

    do you understand  that I am criticizing the logic of microeconomics? If you assume monopolistic (or incomplete) competition,  the problem does not change much. Explanation becomes longer. So, I have illustrated by the assumption of perfect competition (or pure competition, if you like). You may not be interested in the logical structure of a theory, but you cannot mix up contradicting theories. It may increase information but increase confusion at the same time.

  • Jean-Michel Clairand asked a question in Randomized:
    What is the best distribution function for this case?

    I want to generate random numbers from a distribution function. This distribution function has its values defined between [4;24] and has the maximum probability in 7. I attach the density function I want. Do you have an idea of a distribution funtion with its parameters that look like this one? Thank you

  • Leonid Shumlyanskyy added an answer in Tectonics:
    How much energy has the Earth?

    The heat deep within the Earth is what keeps the pulse of our planet - creeping tectonic plates, volcanic eruptions and the activity of the magnetic field.

    These planetary processes are performed with two types of energy: primary energy, or the heat left over from the formation of the Earth and nuclear energy or thermal energy produced during the natural radioactive decay.

    What do you think - today, 4.6 billion years after our rocky home was formed - how much of this energy has left in the inner parts of our planet?

    (I would appreciate it if you up-vote the question if you like it, as well as the answers you like)

  • Kirsten Heimann added an answer in Algae:
    Dose response curves: is better to create different models or just one?

    Hi all,

    i am using R-studio to create a dose-response curves using drc package.

    I have different algae species and same drug concentration for all algae species.

    I want to create a model for each algae species and all drug concentration.

    in the "y" axes i have mortality and each species have different sensitivity to the drug, therefore the curves have slightly different shape.

    at the moment i create a unique model using m1<-drm(Response~Dose, Treatment, data = data, fct =LL.5(names = c("Slope", "Lower Limit", "Upper Limit", "ED50","f"))) function but this means that some curves have better fitting then others......

    question 1: do you think i have to model the species separately and then plot them in the same graph?

    question 2: how i can compare different curves (algae species) to see if there is statistical duifferent between one specie and an other at a particular drug concentration?

    question 3: anyone has an idea how to use ggplot2 package to plot drm model from drc package?

    thanks in advance,


    Kirsten Heimann

    Hi Danilo,

    There are standard models for dose response cytotoxicity curves, which I suggest you use. For comparing toxicicty between the different algae, I would suggest, you calculate IC10, IC50 and IC90 values, which can than be compared using one-way ANOVA.

    To do this, you can use this equation:

    ICF= ((100-F)/F)1/H * IC50

    Where F equals the fraction of maximal response, e.g. for IC90, F=90 and H is the Hill's slope of the cytotoxicity curve.

    Why re-invent the wheel?


  • Sebastian Schmitt added an answer in Nerve Tissue:
    Can someone give me some advice on how to use image j to count the number of axons in a TEM microscope sample tissue slice of nerve tissue?

    So I have been using youtube and online resources to try to measure the amount of axons in this picture I have attached, but honestly I believe the pictures people on youtube are doing are alot less complex than this 
    can anyone point me to useful links or advice on the process to properly count this

  • Sivasubramanian Ramani added an answer in Autodock:
    How to execute autogrid when i have an error 2 msg, how to rectify it?

    Python 2.5.2 (r252:60911, Feb 21 2008, 13:11:45) [MSC v.1310 32 bit (Intel)] on win32
    Type "copyright", "credits" or "license()" for more information.

    Personal firewall software may warn about the connection IDLE
    makes to its subprocess using this computer's internal loopback
    interface. This connection is not visible on any external
    interface and no data is sent to or received from the Internet.

    IDLE 1.2.2 ==== No Subprocess ====
    >>> ERROR *********************************************
    Traceback (most recent call last):
    File "C:\Program Files (x86)\MGLTools-1.5.6\lib\site-packages\ViewerFramework\VF.py", line 898, in tryto
    result = command( *args, **kw )
    File "C:\Program Files (x86)\MGLTools-1.5.6\lib\site-packages\AutoDockTools\autostartCommands.py", line 964, in doit
    ps = subprocess.Popen(args)
    File "C:\Program Files (x86)\MGLTools-1.5.6\lib\subprocess.py", line 594, in __init__
    errread, errwrite)
    File "C:\Program Files (x86)\MGLTools-1.5.6\lib\subprocess.py", line 816, in _execute_child
    WindowsError: [Error 2] The system cannot find the file specified

    Sivasubramanian Ramani

    Am new to docking studies, but this is very crucial for my studies kindly help in sorting this problem where am not able to run autogrid also

  • Moiseev K. G. added an answer in Water:
    How can I determine water absorption and water adsorption of soaked aggregates materials?


    Moiseev K. G.


    Please specify  your question.  The water-saturated of aggregates soils?

  • Gaurav Mudgal added an answer in Plant Tissue Culture:
    Is it legitimate to posit gastric gavage method of animal treatment (with test compounds) equivalent to normal oral administration?

    I have come across publications where the intending author(s) have used the term oral administration in one section (abstract) and then detailing it in the body of the manuscript as to be a gastric gavage method in actual (in the materials and methods section). The question is how legitimate would it be to hypothesize the equivalence of effects of a compound (say a herbal drug/extract) in rat administered via oral route (starting from the buccal cavity) Vs that by bypassed gastric gavage regimen? 

    Gaurav Mudgal

    Thanks Munir... 

  • Grieg F. Steward added an answer in Gel Electrophoresis:
    Can mineral (bottled) water be used instead of distilled water for gel electrophoresis?

    I have a question that may sound silly. Can meniral water (and by that I mean commercial water purchased with the purpose of drinking) instead of distilled water that is usually used for the preparation of agaorose gel and TAE buffer.

    Grieg F. Steward

    Yes. You can. The ion concentration in most electrophoresis buffers is much higher (ca. 10-fold)  than that in typical tap water (whether out of the tap or bottled for drinking) and will have little consequence on the resulting current. However, you should consider switching from TBE or TAE to a Tris-free, low-ionic-strength buffer, such as 5 mM lithium boric acid or sodium boric acid (neither the Tris nor the EDTA are really needed; Brody and Kern 2004). This saves time and money on electrophoresis media preparation, and saves time when running the gels. For a medium that is free of Tris and has low ionic strength, the gel can be run at much higher voltage without overheating (e.g., I run DNA gels at 300 V or about 60 V/cm in 5 mM lithium borate and get the results much quicker than I could with TBE). For these lower ionic strength media, some tap water or bottled drinking water may then have enough salts to influence the results.  But this might simply mean running the gel at a rate slower than might otherwise be possible (but still faster than is possible with TAE or TBE).


    Brody, J. R., and S. E. Kern. 2004. History and principles of conductive media for standard DNA electrophoresis. Anal Biochem 333: 1–13. doi:10.1016/j.ab.2004.05.054

    Brody, J. R., E. S. Calhoun, E. Gallmeier, T. D. Creavalle, and S. E. Kern. 2004. Ultra-fast high-resolution agarose electrophoresis of DNA and RNA using low-molarity conductive media. BioTechniques 37: 598, 600, 602.

  • Majid Mobini added an answer in Correlation:
    Cross correlation of two chaotic sequence?

    assume that a chaotic signal generator generates two ore more chaotic sequences with different initial values. have this sequences different  cross correlation values?

    Majid Mobini

    thanks dear professor,mutual information based methods (such as generalized mutual  information method, pompe,1993) are analyzed for long time series with many possible different values. whether this method is  true  for short  binary sequences with two values 0,1?

  • Daniel Ibarra Marinas added an answer in Mangroves:
    Any GIS appilcations/method that can be used to monitor the regeneration and regrowth of mangroves?



    Daniel Ibarra Marinas

    About NDVI:  http://earthobservatory.nasa.gov/Features/MeasuringVegetation/

  • Michelle Titunick added an answer in Bone:
    Protocol for Frozen Undecalcified Bone Sectioning

    I'm looking for a good protocol for sectioning frozen undecalcified rat bone.  My peptide of interest is very small and vulnerable to degradation (it will probably not survive decalcification or processing for paraffin embedding).  I am able to embed bone in OTC and section using a disposable blade however the sections are very ragged.  I've heard about the Kawamoto tape method and the cryoJane method, but I was hoping there was a less expensive solution.

    Any advice would be greatly appreciated.  Thank you.

    Michelle Titunick

    Thank you.  I'm using femurs.

  • Andrew Paul McKenzie Pegman added an answer in Global Positioning System :
    How can I analyze a huge data set that is highly inflated on one side of its distribution?

    For three years we had 6 birds deployed with GPS devices that transmitted the GPS location of the birds every hour during day time. This resulted in almost 50 000 data points. From these data I calculated the distance covered by the birds between consecutive point. As these birds (shoebills) do not move a lot, more than 90% of the distances covered are between 0 - 1 km. There seems to be no transformation that can deal with this enormous inflation of values between 0 and 1. The range of distances is 0 - 48 km, the average is 0.56 km (SD = 2.5). I tried several Generalized Linear Models, and even though the outcomes make sense when looking at the data, the distribution of the model residuals show a very skewed distribution. Does anyone have experience with a similar data set and knows how to analyze this?

    Andrew Paul McKenzie Pegman

    I also used the Fitdistr package in R to determine the shape of seed dispersal kernels, which have similar distributions to those you describe. But you should summarise the data (mean, median, mode, etc.), determine the best-fit distribution, and possibly consider normalising the data.

    Andrew :-)  

  • Sylwester Kłysz added an answer in Plantar:
    How can I measure fatigue for 2 tennis players after play a match?

    I would like to measure fatigue representing the same match to the 2 players face each other. Would carry out a pre post plantar pressure test and evaluate how fatigue affects the plantar pattern. Thanks

    Sylwester Kłysz

    It does not make sense - always the player who lost the match will be more tired.

  • Marius K. Somda added an answer in Radar:
    Free access to any radar tool for measurement of surface deformation?

    Dear RG members

    Thanks advance for providing information related to free access to any radar tool for measurement of surface deformation.



    Marius K. Somda


    Please find some explanation in this abstract:

    Surface deformation monitoring can provide valuable constraints on the dynamic behaviour of a reservoir, by allowing the evaluation of volume/pressure changes with time, as well as an estimation of reservoir permeability. Levelling campaigns, tiltmeters, GPS and InSAR are all geodetic techniques used to detect and monitor surface deformation phenomena. Among them, InSAR data from satellite radar sensors are gaining increasing attention for their unique technical features and cost-effectiveness. In particular, Permanent Scatterer InSAR (PSInSAR™) is an advanced InSAR technique, developed in the late nineties, capable of providing very precise 1D displacement measurements along the satellite line-of-sight (LOS) and high spatial density (typically exceeding 100 measurement points/sqkm) over large areas, by exploiting point-wise radar targets already available on ground. Recently, some significant advances have been reported in InSAR data processing that can further increase the quality and the effectiveness of this data source for reservoir monitoring: (a) the development of new InSAR algorithms and in particular the so-called SqueeSAR™ approach, which allows a significant increase in the spatial density of measurement points; (b) the availability of an increased number of satellite radar sensors characterized by higher sensitivity to surface deformation, higher spatial resolution, and better temporal frequency of acquisition.

    You can find more informations in the following publication: Measuring Surface Deformation using Satellite Radar Sensors - a Powerful Tool in Permanent Reservoir Monitoring. 'Andrea Tamburini et al. 2011. DOI: 10.3997/2214-4609.20145216.

    Good luck

  • Daniel Hogan asked a question in Homologous Proteins:
    What is the best tool for aligning the structures of homologous proteins?

    I'm trying to align the structures of 3 similar MHC class I molecules. I was wondering what the best tool for performing this alignment might be? Thanks!