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  • Armin Shirzadian added an answer in Cannabinoids:
    What is the reason for intermittent effects of AM251, a specific CB1 receptor antagonist?
    AM251, a specific CB1 receptor antagonist, has dose dependently intermittent weak and strong pro-convulsive effects in seizures following administration of pentylene tetrazole as a convulsant in animal studies. In my opinion the mechanisms that mediate this effects would be interesting.
    Armin Shirzadian · Tehran University of Medical Sciences

    Many thanks.

  • Anjali Somal added an answer in Osteogenic Differentiation:
    Can we use the same osteogenic differentiated cells for mRna expression after vonkossa staining ?

    can we extract RNA from such such cells

    Anjali Somal · Indian Veterinary Research Institute

    jst want to see whether it is expressed or not

  • Alwynne B. Beaudoin added an answer in Publication:
    What is a DOI?

    in filling out your publication form, a DOI is requested

    Alwynne B. Beaudoin · Royal Alberta Museum

    This stands for "digital object identifier". See www.doi.org for more information. It is a persistent (permanent) identifier for a digital object, such as a publication. Most publishers are now assigning DOIs to papers that they publish. 

  • Eugene F Kislyakov added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Eugene F Kislyakov · Belarusian State University

    See You tomorrow.

  • Asia Saadullah added an answer in Botrytis Cinerea:
    I want to ask if my isolates of Botrytis cinerea will remain viable after being out of refrigerator for 16 days?

    For those who has an experience about the fungal growth and storage,

    The problem is that the isolates remain in customs without storage during the mentioned period and it takes long before they understand the importance for storing them in refrigerator.

    I am in a big need of these isolates but i do not know whether they will be viable and perfect for my experiments or not ?

    Asia Saadullah · University of Duhok / Faculty of Science

    i think it is viable if the temperature is  25

  • Jose Geraldo Vidal Vieira added an answer in Social Research:
    Is the use of Likert scale in social research or similar an easy choice?

    Dear, which scale is more suitable to use in questionnaire design (survey) in order to get the perceptions of respondents related to any matter? This question seems to be very easy, but many researchers use 1-7 Likert scale; others use 1-5; 0-10 etc and they do not show reasons to this choice. Could you give me any technical reasons, please?

    Jose Geraldo Vidal Vieira · Federal University of Sao Carlos/CCGT

    I totally agree that the purpose of the study is the main issue. However, in turn, to capture the details of the attitudes/perceptions of the respondents in my opinion is not so easy. It depends on other facts as well, such as the questionnarie design, use of the paper form instead of on-line survey, etc. My phd. was about "Collaboration in Supply Chain". My concern was in understanding the term "Collaboration" and its impact of "logistical performance indicators". I used many variables to summarise those constructs. In order to capture those meaning, I tested 3 scales (1-5; 1-7 and 0-10) with 15 participants and the results showed us that the 0-10 scale was more suitable than the other ones. The respondents felt more confortable (more natural) and faster to understand this range, maybe because in Brazilian culture this scale is very known, instead of 1-7 scale for example.

    Thanks everyone for your collaboration.

  • Narayanan Bhattathiri added an answer in Linguistics:
    English as a lingua (NOT) so franca - What's the meaning of the term "hypostatized"?

    Can anyone clarify the following expression by O'Regan (2014, p. 539)* which I have highlighted in bold:

    "Rather than in its real form as Englishes of various kinds in contact, 'ELF' appears instead as an irreal and especial hypostatized form so that – to play on Marx’s words – in the fetishism of English as a lingua franca the linguistic pragmatic interactions of speakers of different first languages assume the nature of a fantastic relation between speakers of an hypostatized universal code".


    *"English as a lingua franca: An immanent critique", Applied Linguistics, 35(5), 2014, 533–552.

    Narayanan Bhattathiri · Sansar

    Dear Sergio

    I have no religious trauma, please do not assume such things; nor do I have any post-colonial trauma. There are hierarchies ein every part of the world, and the positioning concepts differ. What I gave is just my impression on what english as lingua franca of one group is considered, especially spoken ("English as she is spoken"), and this is very much different in other parts of the world when compared to actual english. It is a fact, that is all, and any one will be right to consider that English as hypostate, in my opinion. Of course such an english is likely to be full of fallacies (as far as grammar, etc., is concerned)

    As regards etymology, the 'state' (state of affairs) I gave is same as the being, existence, etc given by Avra.


  • Subhash Kalluri added an answer in Exosomes:
    Can anyone help with resuspending Exosomes in Nanopure water?

    I am curious to know if any researchers have experience with resuspending the Exosomes in Nanopure water. I am interested to know the long term and short term stability of these particles. Based on my experience, we resuspend the cells or any biological materials in PBS or electrolyte solution to maintain the plasma osmolality. I wondering if the same principle applies to these particles of biological origin.

    Thanks your answers. 

    Subhash Kalluri · Izon

    Hi Anne, I will definitely go through the paper. Thanks a lot for your response.

  • Oluwafemi Samson Balogun added an answer in R Programming:
    Is there a good resource for translating SPSS syntax to R code?

    Like many in my field, I learned statistics while using SPSS heavily.  I am trying to migrate/experiment with R, and my largest hang-up is translating what I get from SPSS to R code.

    For example, in SPSS I like the way frequency tables are generated -- I would love to know the R code that would generate an equivalent of that.  Anyone have any recommendations?

    (Note:  I'm not asking for the translated R code, more a resource that can serve sort of like a translator....but with syntax/code instead of language). :)

    Oluwafemi Samson Balogun · Federal University of Technology, Yola

    I think what you should do,is to download a material on how to use R code instead of looking for the spss syntax to R.

    Best of luck

  • Muhammed Arif Şen added an answer in PID Control:
    How can PID controller gain be increased?

    In controllers i'm using the PID controller.  I need to increase the gain, for that what should I do.

    Muhammed Arif Şen · Selcuk University

    You can tunned PID gains with several methods. The most common is trial and error. Ziegler-Nichols is traditional method. Also swarm-based optimization techniques can be used.

  • Asia Saadullah added an answer in Mycelium:
    What is the name of this mold?

    Does anyone know what it could be?
    Mycelium is grey.

    Asia Saadullah · University of Duhok / Faculty of Science

    Aspergillus clavatus

  • Neeraj Pandey added an answer in Discrete Cosine Transform:
    How to implement Discrete Cosine Transform (DCT) in MATLAB?

    How to implement Discrete Cosine Transform (DCT) in MATLAB. Can anyone provide code for it?

    Neeraj Pandey · Defence Research and Development Organisation

    Thanks very much.

  • Aharon Wanszelbaum added an answer in Telemedicine:
    Is Telemedicine part of information sharing ?

    Anyone can provide me a reference prove that telemedicine ia a part of information sharing 

    Aharon Wanszelbaum · meuhedet health service

    I thought twice about your question.As all of us above mentionned and using telemedicine are on the same mind that it is information sharing,I wonder what is the rationale of your question or otherwise put what does really bother you? I have the feeling that maybee we missed the point and we did not really have brought you the answer you are looking for. Is it right ? 

  • Prakash Patel added an answer in Nutrition and Dietetics:
    Will a single 24 hour recall adminstration help me achieve my objective?

    i want to assess nutrient intake of pregnant women in a certain County. I have a sample size of around 300 respondents. Will a single 24 hour administration help me achieve my objective? what are the scientific recommendations? Kindly help

    Prakash Patel · Surat Municipal Institute of Medical Education & Research

    yes, definitely. I think for a sample size of 300 single 24 hour administration is very valid tool to assess nutrient intake. Even in less sample it is found equivalent to a semi-quantitative food frequency questionnaire. You can refer following for the same.


  • Shelley Minteer added an answer in Biofuel Cell:
    Does anyone have a procedure on how to mount enzymes to a enzymatic fuel cell?

    Looking to make a bio-fuel cell with GOx as the anode enzyme and BOx as the cathode enzyme. 

    Shelley Minteer · University of Utah

    quinones, ferrocenes, and osmium complexes are most common and all work well, but they need to be immobilized. typically, this is done in a redox polymer (i.e. Heller work). some of these polymers are easier to synthesize than others.

  • Sinan Ibaguner asked a question in Latin:
    Why english is considered to be the best language in doing science ?

    English (in fact more than 95 % of words are mixture of Latin + Greek + French) is the international world language in almost everything and most scholastically communicated with more than all academic papers being in English ? Is the reason of being the most influential language is science due to (1) advances, discoveries, inventions and contributions made by British & American scientists or due to (2) English have roots of Latin (official language of Roman Empire)  & Greek ? Or both (1) & (2). Thanks in advance for all commenters & contributors

  • Oluwafemi Samson Balogun added an answer in Basic Statistical Analysis:
    How to use factor scores for further statistical analysis?

    I have used dimension reduction option and obtained four factors, and saved the factor scores as variables. What further analysis can I make using these factor scores (or the variables)

    Oluwafemi Samson Balogun · Federal University of Technology, Yola

    I think factor analysis can work

  • Ke-Wei Zhao added an answer in SDS-PAGE:
    Which commercial gel do you recommend for separating type I collagen in SDS-PAGE?

    Hi, I already work with a hand made gel with a stacking 4% gel and a separating 10% gel to separate type I collagen from conditioned media (supernatant of the culture cell plate), but, the cassete's glass get broken (10 x 10 cm) :( So, I'm looking for the possibility to buy some precast gels, but I can't find any commercial brand that provide this characteristics' gel.

    I use the Laemmli method in a semi-dry chamber and it works good for me. What do you recommend me?? Thank's a lot!

    Ke-Wei Zhao · U.S. Department of Veterans Affairs

    GenScript also offers 4-20% gradient gel with much reduced price and similar quality as Pierce or BioRad.  We switched to that for cost cutting purpose.

  • José Luis Ochoa-de-la-Torre added an answer in Physical Oceanography:
    How can I separate storm and swell waves from a time-series?

    Hello all, 

    I have a wave buoy time-series of significant wave height (Hs) and wave period (Tz). I want to separate the series into swell (long wavelength, far field) and locally generated wind wave (storm) components for some further investigation into wave-tide interaction. Is there a theoretical limit that I can use to classify if a wave observed at time t; Hs(t) and Tz(t), is a "swell" or "storm" wave? 

    Many thanks in advance


    José Luis Ochoa-de-la-Torre · Ensenada Center for Scientific Research and Higher Education

    Having 'integral' properties of the wave field, as Hs & Tz it is IMPOSSIBLE to make a separation; a sum of say two contributions , far & local fields. The reason is that the 'Significant Wave' and 'wave period' are  properties derived from the wave spectra in ALL its contributions (if you only know the sum, it is just out of the question to separate 'contributions'). Only if you have the time series from which such integral properties were estimated, then it is (if the local and far fields have 'non-overlaping' spectra) plausible a separation.....via computing spectra & figuring out which peaks /bands to add as separate contributions.

  • Oluwafemi Samson Balogun added an answer in Logistic Regression:
    Why are my data not in 0/1 form?

    I am attempting to conduct a logistic regression for a tennis analytics project, endeavoring to predict the probability of a player winning a point in which he is the server. My response variable (service points) is binary in the sense that it can have only two outcomes for each observation - a success (service point win) or a failure (service point loss).

    I have an issue with my data: For a given player, I have the point by point data for hundreds of matches. So take my data for R. Nadal as an example:

    250 matches, each with about 70 dependent variable observations (service points). So for each match I currently have the two variables: Total_Service_Points_Played andTotal_Service_Points_Won.

    Eg - Match 1: Total_Service_Points_Played: 70 ; Total_Service_Points_Won: 47

    So my data isn't in 1's and 0's. Is there a way I can implement a logistic regression with my dependent variable observations in their current form? Is there any simple transformation that comes to mind?

    What springs to mind for me is to flesh out my match data into 1's and 0's. So following on from Match 1 above I would have: 47 1's followed by 26 0's . My data doesn't provide information as to what sequence these 1's and 0's arrived in, but since the depdendent variable observations are i.i.d this won't cause an issue? Correct me if I'm wrong please. Another issue posed by this technique would be the massive increase in my data - from 250 observations as a ratio (service point wins/service points played) to 250*70=17500 observations or more.

    Oluwafemi Samson Balogun · Federal University of Technology, Yola

    I agree with Alex

  • Herminia Lopez added an answer in Histomorphometry:
    How I can do the histological analysis of wound process?

    The Project which I'm evaluatingis about the healing effect of two medicinal plants by topical management in a murine model .
    Among the specific objectives is to evaluate the histological changes that occur in the skin of rats treated
     The skin sample was taken when it was already formed scar . I have problems with the histological  analysis.
    How to know which plant was the one with the best effect ? I read different articles and make mention of solitary
    Cells, for example, amount of fibroblasts, etc. I want to know if it is correct Make a Difference Taking into : account the thickness of the layers of the skin, intended to do through histomorphometry , or what kind
    Analysis should do whatever para saber had the best effect on healing
    I would thank you for your opinion and advice

    Herminia Lopez · National Polytechnic Institute

    thanx Kaveh Darabi 

  • Praveen Agarwal added an answer in Fractional Calculus:
    Fractional derivative?

    There are many definitions of  Fractional derivative in the literature. In most of the research articles people are using either Caputo or Riemann-Liouville fractional derivative. My question is why people are preferring these two definitions over other?

    Praveen Agarwal · Anand International College of Engineering

    I agree with the answers of Dabiri

  • Andrey Luchnik added an answer in 16S RNA:
    What should I do if I got many bands in 16s RNA gene, increase or reduce annealing temperature of the primers?

    iam trying to amplified 16sRNA and i got these band and i try with other bands but i face a problem with these 2 different strains. if possible i need clear answer by steps

    Andrey Luchnik · Russian Academy of Sciences


    You are not horse, indeed. But why you have hoofs on your legs like a devil? I see them on your feet. 

    Sorry for my frankness and straight-forwadness.

  • Kaoru Aou added an answer in Interferometer:
    What is the use of Michelson interferometer in FTIR?

    can any one acknowledge about the use of michelson interferometer  in FTIR.

    Thanking you


    Kaoru Aou · Dow Chemical Company

    The interferometer allows you to convert the **frequency information** contained in your light (glo-bar; laser is usually in the instrument for calibration as well) into *time/intensity* information, by just having a fast-enough response detector + a moving mirror.  So if you have a HeNe laser for example (essentially just one frequency, with a sharp band in the frequency-intensity plot), you will get a sine wave as your moving mirror moves back and forth.  So imagine the same thing happening with all the frequencies present in your glo-bar (most likely that is your source radiation in the instrument) -- you'll get a combination of various sine waves with different periods corresponding to the frequencies of the radiation.  Your interferogram is a sum combination of all those sine waves.

    Now, what this means is, you have the so-called *time domain* information that can be converted to the *frequency domain* (through Fourier transform, done either via specially programmed hardware on the FT-IR spectrometer, or else can be done via software nowadays, though that's slower usually) --> that is, you get your FT-IR spectrum.

    So in  summary, your interferometer is in effect doing the inverse Fourier transform of your incoming radiation from the *frequency domain* (which you could usually only measure with a diffraction grating or other frequency-sensitive detection method) to the *time domain* (which just requires that the detector be able to refresh quickly enough, or else that you move the mirror slowly enough so that even a cheap detector can detect the intensity of radiations as the mirror position changes).

    Example:  If you use the so-called DTGS detector, you can get pretty good spectrum, as long as you do not need to get spectrum very frequently and/or get high resolution.  But if you use the so-called MCT detectors, which refreshes more quickly (and usually needs to be cooled), you can get higher resolution spectrum and/or get spectra very frequently.

    Sorry for the long explanation - let me know if you need clarification.

  • Abdullah Awad Alhaddad added an answer in Digital Marketing:
    Are there any good, reliable ways to measure marketing effectiveness on social media?

    A lot of companies are using Twitter, Facebook, Pinterest, etc. to try to drive brand engagement and awareness.  My impression is however, that they don't really have a way to assess what all that does for their business in terms of sales or profits.  

    Abdullah Awad Alhaddad · Higher Institute of Business Administration


    Kindly find the attached file regarding my research . May it helps you.

    best regards,


  • Alexander E Kaplan added an answer in Special Relativity:
    Is there a solid proof of non existence of the absolute reference frame or no one has found the proof yet?

    Special Relativity tells us there is no privileged frame but these are just words in Einstein's seminal paper. In Einstein System the assumption of equal speeds of light in both direction cleverly relieves us from the necessity of having one, but as I see it it is just a convenience. But where is the proof?

    I think Galilean view is more likely to lead to the conclusion of non existence the absolute frame than Einstein's.

    Alexander E Kaplan · Johns Hopkins University

    @Sergey: "As well as the CMB cannot be rigorously defined as some absolute frame, since there is, for example, a non-zero probability that just Earth is at 3D rest, when measuring the Doppler dipole humans measure in the reality some “CMB wind”..." Ha? Any explanation of what you tried to say?

    As to your  paper attached to your post -- any biblio data on it? (journal, volume, etc, and date). Is it citeable? It looks like you've prepared/submitted it to one of APS journals (PACS, etc) -- was it ever published? (or even submitted?)

  • Tanisha Mewara asked a question in Publisher:
    Research work on caffiene effects?

    the pros and cons or any important point i could search over for publish paper?