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  • Chen Gafni added an answer in Praat:
    How do I calculate the Breathiness Index?

    I am trying to calculate the Breathiness Index, suggested by Fukazawa et al. (1988), as a measure for breathy voice. The paper indicates a range of 8.3 to 75.7 for values of BRI, but my calculations yield values at an order of 1015.

    I refer to the definition of BRI as the ratio between the energy of the second derivative of a signal and the energy of the non-derived signal.

    I performed the analysis in Praat. The original sound was converted to a matrix, then I applied a formula ((self [col+1] - self [col]) / dx) twice, to obtain the second derivative, and cast the matrix to a sound. Energy was calculated using the Get energy command (which calculates the integral of the squared signal between two time points).

    Any idea what I am missing here?

    Alternatively, can anyone suggest another measure for spectral tilt that does not require an arbitrary cut-off frequency between low and high frequencies?

    Chen Gafni

    Thank you for replying. I attach a short sound (a single vowel).

    I transformed the sound to a matrix because this is what I was told that is necessary to calculate the derivative of a signal. 

    I also tested the method with a sound I prepared from a formula (simple sine wave), for which I could analytically calculate the second derivative, as well as the energy integrals. The results of the analytic calculations and those I described above yielded similar results (it makes sense that the integral of the second derivative produces much higher values compared to the integral of the original signal, because the second derivative of a sine function is the original function multiplied by a positive number). So I am actually concerned that I didn't understand something fundamental about how BRI is defined.

  • Shiva mohammadi moghanjoghi asked a question in Software:
    How can I get the software Powerstats version 1.2 (Promega Corp.) to calculate power of discrimination (PD) and EC?

    Trying to get Powerstats version 1.2 (Promega Corp.) software, but is is not available. how can I get the software to calculate power of discrimination (PD) and a prior exclusion chance? The STR population genetic statistics can not be calculated with other way.

  • Saeed Vafaye asked a question in Software:
    How can i analysis IHC images?

    Image J software is the best choice for analysis!!!!??? if not which software you

  • Morgan Lei added an answer in Computer-Assisted Diagnosis:
    Any solutions for aided pathologic diagnosis?

    I'm going to develop a software to do computer-aided pathologic diagnosis in medical field. But I'm not sure if there is any exsisting good solutions for this. Does anyone know about this? Please tell me or give me some references. Thanks a lot in advance!

    Morgan Lei

    Dear Dr. Jose Luis Garcia Vigil

    Thanks for your detailed answer and helpful suggestions.

    My basic idea is using machine learning algoriths to do the job. Like you said, a catalog of standard images and abnormal images should be used. The features of these sample images will be extracted and learned by some kind of machine learning algorithm. After learning some samples, it should be able to do some pathologic diagnosis work. This learning process may need to be updated as images become more and more.

    What I'm not quite sure are what features and learning algorithm will be suitable for computer-aided pathologic diagnosis.

    MATLAB is a good tool for taking experiments and implementing ideas fast.


    Morgan Lei

  • Quddusi Bashir Kazmi asked a question in Cnidaria:
    Experts in cnidaria,kindly help?

    All pics from Karachi intertidal and subtidal,pics1&2 are of same specimen identified as

    pics  5&6 are of same specimen

    + 9 more attachments

  • Nikolay Raychev added an answer in Python:
    Do you use Python programming language in your scientific research?

    Do you use Python programming language in your scientific research?

    Nikolay Raychev

    I've developed my own quantum computational IDE with Python

  • Adnan Pitafi added an answer in Business Administration:
    Why do you think engineers and other technical graduates prefer pursuing MBA?

    It's popular among engineers and other technical professionals to pursue an MBA (management/ business administration) across the world. As the individual purpose and preference may widely vary between countries, I sincerely request you to share your views as well as your country-wide practices.

    Adnan Pitafi

    Being an Engineer myself and an MBA my motivation was to have a managerial qualification so that further down the line if a promotion came towards purely managerial responsibilities then I would have an edge over other section managers.

  • Ksh. Newton Singh added an answer in Big Bang:
    Are particles created from the energy released during the Big Bang? During expansion, does the energy continuous converted into matters?

    We have learnt from the big bang cosmology that all the particles was created after the big bang explosion. My question is that whether these particles was created from the energy released due to the big bang? If yes, the energy density must be decreases during the course of expansion as it is continuously converting into masses or matters. Again if it happens so, the mass of universe must be increasing with time or expansion.

    Please some give some light on it. I'm working on a solution of Einstein's field equations and I got an expanding solution with an initial singularity. As the time increase to future, its mass and radius increases. So I need to explain the increase in mass with time.

    Ksh. Newton Singh

    Dear Dr. Javadi, there is recent articles on that. In that paper what they consider is that during the formation of Hawkings radiation, negative energy particle will fall inside the singularity and positive energy will escape outside the event of horizon. So falling of negative energy particle makes the energy of the singularity negative and thus possess a negative pressure or back reaction.This negative pressure opposes the formation of singularity. However they also shows possibility of formation of trap surface temporarily. 

    For more details please see these references.

    + 1 more attachment

  • Rahimi Ali added an answer in Language Testing:
    Do you know any error analysis studies which combine the use of learner corpora with pyscholinguistic research methods, such as think-aloud analysis?

    My initial idea is to conduct error analysis research into "some" and "any" as follows:   1) I  will use learner corpora to determine the errors which learners make with these words at different proficiency levels ;2)  I will design language tests based on these errors; 3) I will either ask learners to think aloud while performing the tests or to provide reasons for their answers straight after the task. ( I am as yet undecided as to whether to use on-going think-aloud protocols or retrospective ones).

    For this reason, I would be particularly interested to know of error analysis studies, in English or any other language, which combine the use of learner corpora with think-aloud protocols. However, I am also interested in studies which combine learner corpora research with any other psycholinguistic research method.

    Rahimi Ali

    pleasure chris , 

    good luck with your study


  • Victor Cojocaru added an answer in Nonionic Surfactants:
    What is the freezing point of Tween 80?

    Can anyone help me with an answer and reference to my question? Thank you in advance.

    Victor Cojocaru

    I need to interpret a DSC curve for a microemulsion and I do have 2 exothermic peaks when cooling the sample: one at around -20C and another at approx. -28C. I`m not sure to what component to assign these. The microemulsion is made of Tween 80, 1-butanol, isopropyl myristate and water.

  • Faris Alshubiri added an answer in Taxation:
    Is there research on taxation of cross border projects in the oil and gas industry?

    Dear Scholars,

    Anyone has idea of existing publications on Petroleum Taxation relating to Cross border Oil and Gas Projects? Any suggestions?

    Faris Alshubiri

    Dear Jane Akadiri

    See the two attached files one of them paper related to your subject and another is many paper titles related to your subject can used .

    Best Regards

    + 1 more attachment

  • Caner Yıldırım asked a question in Patch-Clamp Electrophysiology:
    I realize that most of cells which I did seal is glial cells. What could be reason for it?

    Hi, I new started patch clamp electrophysiology techniques and I m working in the cohlear nucleus neurons but I cant distinguish neurons and neuroglia in this area. How do I overcome it. Also would you give me some references /resources for current clamp analysis. thanks.

  • Prasenjit Maity added an answer in Column Chromatography:
    How do I pack a column with sephadex LH 20?

    I am going to use Sephadex LH 20 (from GE) with chloroform as the solvent for separation of my compounds. Can I use pure (100%) chloroform for packing the column? I am asking it, because in GE's manual they have written of using chloroform with 1% ethanol as the solvent for packing the column? Can anyone help me whether pure chloroform is not recommended for it?

    Prasenjit Maity

    Thanks for your comments. It went smoothly. 

  • Shabir H Wani asked a question in Maize:
    A cross between Maize GM-6 and C-8 , both are white ?

    when grown under isolation resulted in white types but few cobs were purplish in colour . what would have been a possible reason?

  • Anjali Roy asked a question in Epigenetic Reprogramming:
    Need the following paper?

    Please provide me this research article. 

    Li, E. (2002) Chromatin modification and epigenetic reprogramming in mammalian development. Nat. Rev. Genet., 3, 662–673.

  • Hari Pandey added an answer in Molecular Dynamics Simulation:
    What is the cause of having bidirectional water molecules motion while implementing a non-equilibrium MD simulation?

    Dear All,

    I am doing non-equilibrium MD simulation to analyze water transport properties through CNT. My model composed of a pool region filled by water molecules and CNT. I have applied an external force on water molecules inside the pool just in Z direction (pore axis). After simulation I expect that water molecules enter the pore from one end. But, via viz I see that water molecules enter both ends of the pore. Is it due to the periodic boundary condition?

    Could anybody let me know why?

    Thanks in advance

    Hari Pandey

    It would be easy to answer if I can see the .mpd and system coordinate file you used. I believe if you applied the pressure difference the water should be the uniderictional . The pbc may not be the reason because pbc only show such behaviour at the boundary but as I believe you have a bulk system and looking at end of CNT. So If you post your  coordinate file like .pdb or .xyz and .mdp file the I can say.

  • Arun Kumar Shrestha added an answer in Methanol Oxidation:
    Which materials are appropriate for codoping on the surface of TiO2 nano tube to increase its photocatalyst activity under the visible light?

    I want to deposit the surface of the TiO2 nano tube to increase the photocatalysis activity under the visible light for the methanol oxidation so which materials are suitable for the codoping on its surface?

    Arun Kumar Shrestha
    1.  I want to proceed the reaction under the visible light by lowering the conduction band in presence of oxygen. So I want to know how to modify TiO2 surface so that it can give better performance.
  • Hassan Younas asked a question in Membranes:
    How could we determine the turtuosity of flat sheet UF membrane?

    turtuosity is one of the factor for membrane "structural parameter" analysis.

  • Stam Nicolis added an answer in Foundations of Quantum Mechanics:
    How do we understand a conservation law (Noether's theorem) in quantum mechanics?

    In the classical mechanics Noether's theorem says that

    "if a system has a continuous symmetry property, then there are corresponding quantities whose values are conserved in time"

    As a simple particular case, a quantity A that doesn't depend on time explicitly, neither through other parameters on which it depends, i.e. dA/dt = 0, is a constant of motion.

    The question is what becomes of this law in quantum mechanics (QM)? Does it hold at all? And if it does, what is its meaning?

    The QM gives the following formula for the time derivative of an operator Ȃ:

    (1) dȂ/dt = ∂Ȃ/∂t + i/ħ (ĤȂ - ȂĤ),

    where Ĥ is the Hamiltonian of the system, and Ȃ is a Hermitic operator attached to an observable of the system.

    Assume now that Ȃ doesn't depend explicitly on time and commutes with Ĥ, therefore dȂ/dt = 0. How shall we understand this result? Does it mean that the value of the operator Ȃ is fixed during the system evolution, even if we don't measure it?

    Or, alternatively, does it mean that performing a measurement of Ȃ on identically prepared systems, we are bound to find the same value of Ȃ?

    In other words, in the QM, a quantity which is a constant of motion, possesses a value, and it is fixed in time, independently on whether we measure it or not? Or, alternatively, it takes a value only if we measure it, and the value is the same if we repeat the measurement on identically prepared systems?

    Stam Nicolis

    Conservation of probability means the system is closed-it doesn't imply anything more. Since the independent variable is time, this means that the ``spacetime'' symmetries are time translation (as a continuous symmetry) and time reversal (as a discrete symmetry). Whether these symmetries are realized, however, and how, depend on the dynamics. That continuous symmetries lead to conservation laws is a theorem, Noether's theorem; here this implies  that, if time translation is a symmetry, then there is conservation of energy, that's realized in a particular way, discussed in previous messages, since, in quantum mechanics, one sums over configurations, that don't satisfy the classical equations of motion, for which Noether's theorem immediately leads to the expression for what can be identified as energy.  Rotations and spatial translations are ``internal'' symmetries and they, too, can lead to conservation laws, when applicable-in general to relations between transition amplitudes (correlation functions) and probabilities. In the context of the experimental setup, as mentioned, unitarity implies that na+nb = N, the total number of particles is conserved, across the bam splitter; it doesn't imply anything about, either the number going in each channel, nor their difference. The detailed properties of the dynamics imply conditions on these quantities. 

  • Masoud Ovissi asked a question in Diamond:
    Which supplier sells ‏Synthetic Diamond Making Machine?

    I need some suppliers selling the machine instead of diamonds.

  • Krishnasarma pathy/ SARMA KRISHNA PATHY asked a question in Vanadium:
    Can some one can help oxisation of 2-napthal to 2-hydroxy -1,4 napthaquinone by using vanadium/hydrogenperoxide?

    Selective oxidation of 2-napthol to lawsone by  vanadium oxide/hydrogen peroxide . other roots also available . by above root  single product of lawsone any one  can help on synthesis 

  • Miranda Yeoh added an answer in Papers:
    Is it acceptable to repeat a same section in several papers describing the same methodology without significant changes ?

    If we have several application of the same methodology for different studies and papers and we can not make significant changes for describing the methodology. What is your point of view? is it acceptable to rewrite the same section without significant changes?

    Miranda Yeoh

    Certain journals allow this.  We just make it clear that we cite ourselves, and put the reference appropriately.  We also can use phrases like: "As described in Yeoh, 2013a, these procedures were carried out in the data collection process....."

    After all, the plagiarism software will find our own paper on the Web.  Even though it highlights the similar parts, it is ok.  But I do not copy a very large block of several paragraphs.  I will rewrite again and re-phrase most of it.  It's useful to scan it myself using Viper, and be sure that the similarity index is low: 1%, 3% is fine.

  • Shreyas Kuddannaya added an answer in Nanoparticle Synthesis:
    What is the role of capping agent in nanoparticle synthesis?

    e.g. in case of gold nanoparticle, the role of trisodium citrate as capping agent. 

    Shreyas Kuddannaya

    Hi Rajni,

    A Capping agent is used 

    1. To Avoid Formation of any undersired cross-aggregation of the nanoparticles during or/after synthesis. 

    E.g: Mercaptoethanol/thio urea used as a capping agent in zns:cu nanoparticle sysnthesis

    2. Prevent the exposure of nanoparticle surface towards reaction with any other functionally active molecules in the solvent. 

    3. In some sensitive cases such as nanoiparticle sysnthesized for molecular diagnostics, it is used to avoid non-specific binding or interactions with the nanoparticle.

    4. Overall, it will stabilize the nanoparticle in solutions and prevent it from degradation (so to some extent might improve i.e shelf life) 

    These are some of my views, Hope they might be helpful.

    Best regards,


  • Rahimi Ali added an answer in English Literature:
    How is Charles Dickens recieved in Algeria?

    Because Charles Dickens is a cosmopolitan figure, I am wondering about his audiences in Algeria and the influence he has upon Algerian EFL writers.

    Rahimi Ali

    hi  abderrezzaq 

    check out this book , it may help :


    also this article :



    best wishes, 


  • Alireza Moosavi asked a question in Chlorella Vulgaris:
    Statistical Analysis of an experiment with a parameter with dependent levels to other parameter levels

    Dear all,

    I have designed a set of experiments to study the effect of different parameters on flocculation of microalgae specie Chlorella vulgaris. The main parameters are OD (optical density) of microalgae cells, pH and amount of flocculant dosage.

    The problem is the levels in dosage of flocculant are not constant and they are dependent to level of OD and pH. For example, in OD=1 and acidic pH, the range of dosage varies between 0-100 ppm, though, in OD=5 and acidic pH, this range varies between 0-1000 ppm.

    Please let me know how I could incorporate these data in a statistical set to run ANOVA statistical analysis on them.

  • Henrik Rasmus Andersen added an answer in LC-MS:
    As can proceed to the analysis of pharmaceuticals submit NaOH, HCl and Fe +2 and H2O2 by LC-MS?

    As can proceed to the analysis of pharmaceuticals submit NaOH, HCl and Fe +2 and H2O2 by LC-MS? I need analyse degradation products in pharmaceuticals by LC-MS. lc-ms it is compatible with these agents?

    Henrik Rasmus Andersen

    From the chemicals your question is on it appears you are doing Fenton oxidation. As long as both Fe2+/Fe(III) and H2O2 is in solution the oxidation will continue.

    The fastest procedure to stop the reaction I know of is to add excess NaCO3 to raise the pH to 10 which will precipate iron. This might also be needed as pretreatment to LC-MS.

    If you experience problems with stability you can additionally add 0.1% methanol which react with the radicals. For some analysis like COD H2O2 interferes with the quantitation and then H2O2 can be destroyed by catalase at neutral pH.

  • Paweł Wawrzała added an answer in Nanogenerators:
    Triboelectric nanogenerators: are there any devices on the market?

    Can devices based on triboelectric nanogenerators are already in the process of commercialization? Any the test versions, development kits for mechanical energy harvesting (converting the external kinetic energy into an electrical energy)?

    Paweł Wawrzała

    Thanks to all for your answers, it remains to wait, because this technology probably has a big future.

  • Ming Lu asked a question in Regional:
    The relationship between CTCF binding sites defined chromatin domain and disequlibrium linkage group?

    Does the linkage group cross the CTCF defined insulator region/loop region or overlap with the region?

  • Marshall Samuel asked a question in Peat:
    Does compaction on peat soil affects CO2 emission?

    Due to the high organic matter content (e.g. 80-90%), the compacted peat soil tend to back to it previous physical structure. But, after reached to certain threshold the compacted peat soil may loss of it plasticity. I assume the compacted soil may provide low oxygen in the affected soil surface, which will also altering the physical structure and microbial population that responsible on CO2 emission (transportation). May I know, is there any study to support this statement? because most studies basically explain the benefits of organic matter application to enhance porosity of compacted mineral soil.