Q&A

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  • Sundus Riaz added an answer in Mice:
    How can I measure Papilloma size in Balb/C mice?

    I want to measure the tumor size in mice, i have given the doses dermally, What will be the appropriate method to measure the papillioma size.

    Sundus Riaz · National University of Science and Technology

    We use vernier calliper...

  • Yong Tang added an answer in Insect Diversity:
    Any experiences, comments or suggestions on insect monitoring?

    We are organising insect diversity monitoring networks in China. 

    I just drafted the talk to present on the 1st Biodiversity Monitoring Conference, China. All texts are in Chinese at the moment. http://blog.sciencenet.cn/blog-536560-860261.html 

    If you have any interests, comments or suggestions, please kindly contact me. Certainly, you are welcome to discuss on potential collaborations.

    cd in Beijing

    Yong Tang · Xishuangbanna Tropical Botanical Garden

    Hi Professor Zhu

    We have conducted a comprehensive monitoring project in Yunnan and Australia and here are some initial results. You could contact Dr. Nakamura @ Xishuangbanna Tropical Botanical Garden for more details about the project.

  • Is a rigid rod moving perpendicularly to x axis (in the standard Special Relativity axes convention) parallel to the moving system x’ axis?

    I had a few discussions of this problem and most people maintain the moving rigid rod always parallel to x is not parallel to x’ even though it is said x' axis is co-linear with x axis which is counterintuitive.

    I maintain that parallelism is preserved by the assertion of possible coincidence and co-linearity of the rod with x axis which is co-linear with x' while the STR formulae after Lorentz transformation seem to indicate otherwise.

    Any thoughts/comments/discussion in that matter will be highly appreciated as they are vital to my research.

    Johan Frans Prins · Sage Wise 66 (Pty) Ltd

    Dear Walter,

    Plesae STOP being so utterly absurd. I can DEFINE that a cat is a dog but that does not make a cat a dog.

    The "definition{ (Oh God help me!) that x^2+y^2+z^2-w^2=0 is a relation in 4D is mathematically impossible, as all mathematicians with brains can attest to. It DOES NOT define a light cone in 4D since there is NO 4D manifold involved, A cat is not a dog!

  • Justin Lemkul added an answer in Gromacs:
    Is this a serious problem at 'make' step during GROMACS 5 installation?

    Hi, all.

    I tried to install GROMACS 5, at GPU system.

    During installation, at 'make' step, I obtained the error below.

    'remark #7: unrecognized token
    #define __storage_auto__constant__ @@@ COMPILER @@@ ERROR @@@'

    Is this a serious problem?

    It seems that all functions are installed.

    Besides, there was no problem at 'regressiontests' according to the gromacs 5 installation instruction.

    Thanks in advance.

    Justin Lemkul · University of Maryland, Baltimore

    Pre-compiled binaries are convenient, especially for new users, but they often leave a lot of performance on the table.  One can gain some significant improvements by compiling specifically for one's hardware and available compilers.

  • What simple outcome measure would you recommend to regularly measure parent rated change in global ASD ?

    Children will be having a variety of non-specific therapies, and the measure needs to be able to be completed by parents, and be considered valid and reliable.

    Philippa Fibert · The University of Sheffield

    I'm assessing the effectiveness of non-specific therapies (the GAPs diet and homeopathy) therefore I'd like to find a measure of global symptomatology. Most of my research has been on ADHD where there are validated, reliable measures such as Conners' rating scales. I'm struggling find the equivalent for ASD.

  • Sean Page asked a question in Action Research:
    What is earliest published account describing action research?

    Lewin 1946 is oft cited but I'm not convinced. Also earlier papers may not always describe action research in its accepted sense. So when did we see a paper that would relate to what could be understood as action research?

  • Can anyone help me to find sources for image processing and improving computer vision ?

    i am doing a research on how to get dimensions of an object form an image! i want some web sites that explanes such topic.

    James F Peters · University of Manitoba

    This is a good question.

    An excellent study of computer vision (its secrets) is given in

    C. Olsson, Global optimization in computer vision: Complexity, cuts and approximation algorithms, Ph.D. thesis, Lund University, Sweden, 2009:
    http://www2.maths.lth.se/vision/publdb/reports/pdf/olsson-phd-09.pdf

    See Chapter 1 for an overview of the state-of-the-art of computer vision.

  • Ahmed Hamed asked a question in Reference Books:
    Need book for computer architecture and organization?

    I'm going to study computer organization and architecture... so can anyone recommend me a reference book.

  • Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Johan Frans Prins · Sage Wise 66 (Pty) Ltd

    Dear Erkki,

    It is late here in South Africa and therefore I do not have the time to go through all your beliefs which, according to my experience (and note that I have probably taught theoretical physics and the incorrect versions of it that you want to believe for many years), are illogical and absurd.

    I do not like your posting as follows: " Again I state that your problem is that you Maxwellize everything to the point that you must invent a “Lorentz transformation" that is singular. Then you can get anything you want! Please address this point!

    I have adressed this poit over and over and over again and have published in many manuscripts that are easily available.

    Why do YOU want to believe that after Maxwell, physics became "weird and absurd? Show me ANY radio-engineer that uses anything else than Maxwell's equations: But since Bohr was bipolar, and Einstein absurd, you also want to believe that these equations do not apply at high frequencies and small scales. Why would they not? And in fact they DO! According to Occams razor one expects that they must.

    And my research has shown, to my own astonishment that they DO! I have published these arguments in detail in my manuscripts, but you refuse to read them and to argue physics as one should argue physics. You rather insult me by accusing me that "I have a problem and "am barking up a wrong tree". I expected more from a man of your stature.

    I did NOT invent a Lorentz transformation: Lorentz and Poincare discovered it and Einstein gave the reason why such a transformation must exisr: Namely the invariance of then speed of light. But he then tripped over his own feet since he, just like Lorentz and Poincare, did not understand Galileo (the greatest physicist who ever lived); and therefore endeduip by assuming that "time-dilation" occurs (which is absurd poppycock) and that "length-contraction" occurs which is equally absurd poppycock!

  • Tobias Sattler added an answer in Benzene:
    Which GC detector would be better to determine benzene below 2ppm level ?

    GC Detector Chromatography Benzene

    Tobias Sattler · Universität Heidelberg

    It depends mostly on your enrichment device in front of the GC. You can go easily down to ppb and even ppt range if you use a trap. For benzene it should be even ok to use an adsorbent, so you dont need liquid nitrogen or CO2 for the trap.

  • Why multi reinforced bars should be used instead of same area satisfied one steel bar?

    For any RCC frame member it is in general to use numerous steel bars to satisfy the required steel area rather than using one high diameter steel bar.  What would be the reason for that?

    Rudra Upadhyay · Arizona State University

    The answers have been quite amazing. Thank you everyone for taking your time out and answering. I was facing this question while I was studying corrosion effect in structural damage.

  • Markus Gschwind added an answer in Waves:
    Brain and phase transitions: which is the role of fractals?

    Many scientists claim that the default brain activity is in phase transition (charachterized by fractals) and that, during perceptions and higher thoughts, there is a bifurcation event and an exit from phase transition.   
    However, we find temporal fractal structures both in low EEG waves and in higher waves (such as in gamma spikes, traditionally associated with perceptions and higher thoughts): if the brain is not anymore in phase transition, the fractals must disappear, but, instead, the slope of fractal exponents
    is even higher in gamma than in alpha waves (Raichle and his group, and many
    others).  

    Which is the explanation of the persistence of bran fractals in all the functional states of the CNS? 

    Markus Gschwind · Hôpitaux Universitaires de Genève

    Dear Arturo and Ashish,

    This is a fascinating topic! Would you mind giving some references where this is described in more detail and where I could read more?

    Thanks!!

  • What is the density of sodium pertechnetate (NaTcO4)?

    density of sodium pertechnetate (NaTcO4)?

    Shaban Ahmed Ali Abdel-Raheem · Assiut University

    Dear friend

    You can see the attached papers . I hope to help you

  • Cesar de Gregorio added an answer in Dental:
    What do yo think is the better treatment for necrotic open apex teeth? Apexification with MTA or Revascularization?
    I consider MTA a predictable method to obtain a sealing in those situations but Revascularization has showed compromising results. Is this technique enough supported in the literature to considered to be the treatment of choice?
    Cesar de Gregorio · King Juan Carlos University

    Dear all,

    Very interesting answers, very similar with my point of view. However, I would consider Revascularization using Apical Negative Pressure, instead of using a cocktail of antibiotics. In this way, we eliminate any possibility of producing crown discoloration and there is enough support from the recent literature demonstrating at least the same results. So, no need to use antibiotics, in my opinion.

    About when to use a Revasc protocol or a MTA plug. It is quite difficult to establish a "line" between both treatments. I try to offer the possibility of a reverse treatment if I consider that the dentin thickness and the development of the root is too poor and could compromise the root strength. BUT, as I said, it is almost impossible to establish a line between both options, at this moment.

    I believe that offering this possibility (revasc) does not close any door, since after a possible failure in a reverse. We would still have the option B, with an apical plug.

    Best regards,

    Cesar de Gregorio

  • Endre Solti added an answer in E-Learning:
    Whats is your opinion regarding the future of e-Learning?

    I am interested to do a prospective analysis about the e-Learning

    Endre Solti · University of Campinas

    I have not seen anyone comment on the teaching of practical content in distance education mode. Have you ever thought, for example, as can teach a person how to cycle through distance education? There are contents that are not verbalizable (procedural content) and difficult transmission by current technological means, as the limitations of existing technologies.

  • Do you have any resource for simulating of a photocatalytic reactor by using COMSOL?

    I cannot simulate the radiation part of the photoreactor.

    Any resource/suggestion is appreciated.

    Thanks in advance.

    Shaban Ahmed Ali Abdel-Raheem · Assiut University

    Dear friend

    You can see the attached papers . I hope to help you

  • Shawin Karim added an answer in Bioinformatics:
    Can anyone suggest good sandwich phd program in bioinformatics?

    for 6months to 1 year time duration

  • Is it possible to study organic chemistry by myself??

    Do I need to have some lab courses to study organic chemistry?

    I am a Biology major, but I don't study organic chemistry.

    I find it troubling.

    Maxim V. Galkin · Uppsala University

    I think that it is possible to manage with theory on your own. And free of charge. Also there is many open lectures online from good universities for all levels. https://www.coursera.org For simple stuff see Khan academy on YouTube.

  • Abedallah M Rababah added an answer in Feces:
    Are you willing to pay for drinking water derived from sewage?

    Bill Gates did it! And you? Are you willing to pay for a glass of that water?

    Is it really safe? Does it have all the nutritional element we need?

    One of the by-products is energy.

    "This Ingenious Machine Turns Feces Into Drinking Water
    By Bill Gates 
    January 5, 2015
     "I watched the piles of feces go up the conveyer belt and drop into a large bin. They made their way through the machine, getting boiled and treated. A few minutes later I took a long taste of the end result: a glass of delicious drinking water.

    The occasion was a tour of a facility that burns human waste and produces water and electricity (plus a little ash). I have visited lots of similar sites, like power plants and paper mills, so when I heard about this one—it’s part of the Gates Foundation’s effort to improve sanitation in poor countries—I was eager to check it out.

    The water tasted as good as any I’ve had out of a bottle. And having studied the engineering behind it, I would happily drink it every day. It’s that safe.

    Here’s a short video from my visit in November, which explains how it all works:"

    http://www.gatesnotes.com/Development/Omniprocessor-From-Poop-to-Potable

    Abedallah M Rababah · Jordan University of Science and Technology

    I do not prefer the idea of paying for drinking water derived from sewage.

  • Renas Isa asked a question in Plant Proteins:
    Hello everyone, I am looking for some recent articles which is related on using animal and plant protein and their effects on egg production?

    Hello everyone, I am looking for some recent articles which is related on using animal and plant proteins and their effects on egg production and quality? thanks in advance

  • Barry Turner added an answer in Intelligence:
    Is it worse intelligence without education or education without intelligence?

    Yesterday at the conference of  the University of Udine in honor of the Doyen Prof. L. C. Piccinini, the director of our Department of Civil Engineering and Architecture Prof. Gaetano Russo said into the microphone, "is one of the smartest people I've ever known." During the coffee break, some other colleagues were discussing saying the Doyen was also a person of wide culture: a true Renaissance scholar.
    But then what is intelligence without culture? And what is culture without intelligence?
    We can make a few examples of where this great combination is distributed differently:
    Shakespeare versus Milton;
    Marconi versus Maxell;
    Mozart vs. Salieri.
    What is your opinion about it.
    Many kind regards

    Ting Fa Margherita CHANG

    Barry Turner · University of Lincoln

    I have never seen the point of comparing scientific, artistic and literary greats.  Culture is not a sport with a league table.  Milton and Shakespeare are equally glorious as are many others.  

    Mozart wrote 41 symphonies but we cannot say that because there are 41 of them that they are 'better' than Beethoven's nine.

    Marconi benefitted from Maxwell's electromagnetic field theory but does that mean it was a contest?

    I am endlessly surprised at the frequency of qualitative value judgements being used on RG.  Silly arguments about human and animal ethics and all too frequent proselytising about 'ancient wisdom'  

    We all stand on the shoulders of giants to paraphrase Newton.  It is of no value at all to suggest that one genius is 'better' than another.  

  • Hesham Gad asked a question in Emulation:
    Does FPGA based emulators of DC motor considered an industrial application?

    I want to emulate a DC motor inside the FPGA to test the performance of a specific control algorithm 

    I just want to know, is such thing consider an industrial application ?

  • Christian Dreger added an answer in RATS Software:
    What software can be used to determine the z-test statistics in the Gregory-Hansen co-integration test?

    I am testing time series data for cointegration with structural breaks using the Gregory-Hansen approach. The software am using to conduct this test is RATS, but the test only provides the ADF test statistics in the standard RATS software package. Can someone explain to me how to obtain the z-test statistics for the Gregory-Hansen cointegration test using any econometric software.

    Thank you 

    Christian Dreger · German Institute for Economic Research

    First, you should use the Engle-Granger ADF critical values, as you are interested in cointegration testing and have to estimate the cointegrating relationship to construct the residuals. For these critical values, the number of regressors are decisive. Second, due to a potential structural break you can treat the dummies simply as additional regressors. As a reference, see Hassler (2004): Dickey Fuller cointegration tests in the presence of regime shifts at known time. 

  • Alireza Jafari.N added an answer in Ground Motion:
    Is there any software for scaling earthquake records?

    To scale the input of ground motion records, what software we can use?

    Alireza Jafari.N · Kharazmi University

    hi  dear Linh Nguyen

     "SeismoSignal" Software is very  good for your purpose,

    You  can  learn it easily

    Best Regards 

  • Susan Mcgilloway asked a question in Mental Health:
    Is anyone on the site conducting research on vicarious traumatization?

    I am particularly interested in studies conducted among clinical mental health professionals.

  • Şahika Sena Bayazit added an answer in Chemistry:
    Can anyone explain briefly the difference between the equilibrium and steady state system in chemistry?

    A system in a steady state means that the rate of change is Zero! what about the system which is in equilibrium? 

    Şahika Sena Bayazit · Beykent Üniversitesi

    Hi Kulthoum, 

    this page can be helpful for you. 

  • What does it mean when a reaction has a rate constant greater than one (K>1)?

    I recorded the concentrations of a product during a reaction. There was an enzyme producing bacteria as catalyzer. Then I plotted the concentration changes versus time and fitted a modified logistic function (based on the related literature; 1st order kinetics) to the plotted data. I found then the rate constant (K) from the fitted function. It was 1.68 1/h. Can it be bigger than 1? if so, what does it mean?

    Seyed Mohammad Mahdi Nouri · Hakim Sabzevari University

    There is no limitation of the value of K, the order of reaction is a function of concentration and not K

  • Amina Mezerket asked a question in Nematology:
    Please,can you help me to find some laboratories and researchers in nematology ?

    nematology,globodera sp,morphometric identification,molecular identification

  • Which type of MgSO4 we used in krebs solution for isolated aortic ring?

    we have the following MgSO4 with CAS number

    7487-88-9    Magnesium sulfate

    14168-73-1 Magnesium sulfate(monohydrate) MW=138.38

    24378-31-2 Magnesium sulfate(tetrahydrate) MW=192.42872

    15553-21-6 Magnesium sulfate(pentahydrate) MW= 210.37

    13778-97-7 Magnesium sulfate(hexahydrate) MW= 228.46

    10034-99-8 Magnesium sulfate(heptahydrate) MW= 246.47

    the molcular weight of all above are different

    we know that we use MgSO4 for Krebs solution with 1.2 mM

    Are their any differences among above MgSO4?

    Can any one tell me when I used one of above MgSO4 may our krebs are correct or not

    Best regard

    Gordon L Warren · Georgia State University

    Yes, you are correct in your calculations. The only thing that matters is the molarity. For a magnesium sulfate(heptahydrate), you will have to add more mass-wise than you would if you were using magnesium sulfate anhydrate. For a hydrate, that extra mass is water and it doesn't matter when making Krebs because water makes up the balance of the solution after adding all the salts.