Q&A

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  • Miranda Yeoh added an answer in Research Papers:
    In your research paper, what information would you present as tables and what information would you describe in your text?

    In your research paper, what information would you present as tables and what information would you describe?  SPSS gives us a lot of data: Reliability and variances, Means and SD's, normality tests, Levene's tests and t-tests and Pearson Correlation Table are some of the usual stuff.  We also need to bear in mind that the journal may only give us 15 pages or 20 pages, and 1 table has to be on a separate page.  What is your view, how would you present your data?

    Miranda Yeoh · Kolej Matrikulasi Selangor, MALAYSIA (Selangor Matriculation College)

    Thanks Behrouz.  Good views indeed, I agree.  When I was a student we used to joke that SPSS can get us anything, even cats and dogs (pets).  It's our Malaysian habit of describing things when we want to say, 'it's such a lot of data.  Let me exercise wisdom to select carefully...'

  • Followiing the protocol of Sigma's non specific enzyme activity assay to determine activity of Trypsin & chymotrypsin.

    I am following Sigma's non specific enzyme activity assay where casein is used as a substrate to determine the enzyme activity of Trypsin and Chymotrypsin. Even  at the best enzymatic condition for Chymotrypsin I am getting smaller specific activity (unit /mg of solid). If anybody could help me with some information about that? Thanks in advance.

    Abu Bakar Siddique · Università degli Studi di Salerno

    I am using Calcium Acetate with Sodium acetate to dilute the enzyme. Thank you.

  • Free math software and tools.
    The following list includes free math software and tools together with the corresponding descriptions and download sites.

    Operating systems:
    Scientific Linux: A linux distribution put together by Fermilab and CERN. Freely available from
    http://www.scientificlinux.org/

    Ubuntu Linux: A Linux distribution, easy to install and freely available from
    http://www.ubuntu.com/

    Debian: Perhaps the best Linux distribution.
    http://www.debian.org/

    DesktopBSD:
    A freeBSD distribution easy to use which can be tested through a live DVD. Freely available from
    http://www.desktopbsd.net/

    BSD: Several Unix distributions.
    http://www.junauza.com/2009/04/5-best-bsd-distributions.html

    Applications for symbolic calculus.
    wxMaxima:
    Calculus with a graphic interface. Freely available from

    http://sourceforge.net/projects/wxmaxima/

    Axiom: Similar to the preceding one.
    http://axiom-developer.org/

    Euler: id.
    http://euler.sourceforge.net/

    Scilab: id.
    http://www.scilab.org/

    octave: id.
    http://www.gnu.org/software/octave/

    Gap: Computational discrete algebra,
    http://www.gap-system.org/

    R: Statistics
    http://en.wikipedia.org/wiki/R_(programming_language)

    PSPP: Statistics
    http://www.gnu.org/software/pspp/


    haskell: Pure and lazy functional programming language with an interpreter.
    http://hackage.haskell.org/platform/

    Astronomy:
    Stellarium: Free astronomy appl.
    http://www.stellarium.org/

    Star charts: Free star charts PDF files.
    http://www.midnightkite.com/starcharts.html

    Math graphics:

    Gnuplot: To build any graphic in 2D or 3D. Freely available from
    http://www.gnuplot.info/

    DISLIN: A graphical library, easy to use.
    http://www.dislin.de/

    Word processors:

    TexMacs: WYSIWYG editor with a graphical interface, by means of which one can type scientific texts, and export them in PDF, PS, HTML, LaTeX formats. Freely available from
    http://www.texmacs.org/

    Lyx: Similar to the preceding one.
    http://www.lyx.org/

    Miktex: A complete LaTeX distribution for Windows. Freely available from
    http://miktex.org/

    TexMaker: A LaTeX editor: Freely available from
    http://www.xm1math.net/texmaker/

    TeXniccenter: Another powerful LaTeX editor for Windows OS.
    http://www.texniccenter.org/

    Kile: Another LaTeX editor.
    http://kile.sourceforge.net/

    TexShop: A LaTeX distribution and editor for Mac OS X. Freely available from
    http://pages.uoregon.edu/koch/texshop/

    Texlive: A LaTeX distribution for Linux and Unix OS'.
    http://www.tug.org/texlive/

    Open Office: A package similar to Microsoft Office:
    http://www.openoffice.org/

    Macaulay2 is a software system devoted to supporting research in algebraic geometry and commutative algebra, whose creation has been funded by the National Science Foundation since 1992.

    http://www.math.uiuc.edu/Macaulay2/

  • Comparison of results by various optimization method

     I want to compare the result with various optimization methods. Which are the parameters to be set equal so that I can compare them on the  common setting. eg. for GA and PSO methods. The stopping Criteria is set same for both i.e. 10^5 .

  • Chithan C Kandaswami added an answer in Music:
    How does music affect our feelings?

    Music interferes with our feelings, enjoyment and to some extent may be a therapeuticc option. Music accompanies most of, if not, all our ativities. What are the effects of music in our nervous system? How do we respond?

    Any views are welcome 

    Chithan C Kandaswami · University at Buffalo, The State University of New York

    Music, dance and language…

    Music and dancing are integrally related; dancing possibly has its origins close to the birth of Homo sapiens, and dancing has been universally practiced in all societies throughout our history.

    Creative dance performance and molecular genetics.
    Open article.
    DOI: 10.1371/journal.pgen.0010042

    http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.0010042

    Bachner-Melman R, Dina C, Zohar AH, Constantini N, Lerer E, et al. (2005) AVPR1a and SLC6A4 Gene Polymorphisms Are Associated with Creative Dance Performance. PLoS Genet 1(3): e42. doi:10.1371/journal.pgen.0010042

  • Wilhelm Wilmers added an answer in Geotechnics:
    Can anyone help with using concrete for improving soil properties?
    The soil in my region is clay and we have problem in stability of it, so I want to do this research and see what the result of it. So, could tell about any practical procedure for doing that.

    I would make different mixtures with clay and for instance 30%, 40% 50%, 60%, 70%, 80%, 90% of bigger particles and test the efficiency by CBR-Test. Than with the best mixture and two adjacent mixtures i would test the effect of cement or cement paste by adding it to the clay-aggregate-mixture. Perhaps the quantity of cement should be tested by mixtures with different quantities of cement with the best clay-aggregate mixture.  A lot of work. Wish a good success.

  • SCILAB vs MATLAB - What software do you use for research work?

    MATLAB is a very powerful, commercial, software with a lot of toolboxes and great Graphic User Interface (GUI). SCILAB is an open-source, free, software, developed by scientists around the world as an alternative to MATLAB.

    Differences between the two softwares include:

    -Language and features
    -User Interface
    -Computation Speed
    -Tool-boxes
    -Source code availability
    -Interfaces to other programs
    -etc.

    What software do you use? SCILAB or MATLAB? Kindly share your views!

    Sundarapandian Vaidyanathan · Vel Tech - Technical University

    Deepak - You may have some critical views on Scilab about User Interface, Graphics, etc., but certainly not on "computation speed". As far as I know, computation speed is a plus point for Scilab. It does calculations very fast, indeed. Best wishes, Sundar

  • Deniz Kilinç added an answer in Algorithms:
    What are the recent trend in algorithm ?

    Actually I'm interested in algorithm and do some research so I want to know about recent trend.

    Deniz Kilinç · Celal Bayar Üniversitesi

    I agree with Daniel. Question is not clear. There are lots of algorithms for different purposes.

    If you don't write the question specificially, we cant see ideas in your mind.

    You can read

    • http://en.wikipedia.org/wiki/Algorithm
    • http://en.wikipedia.org/wiki/List_of_algorithms 
  • Hanno Krieger added an answer in Wellness:
    What is the best form of answers in RG?

    I have seen answers very long, so that no body wants to read them completely. On the other hand the questions remains. I believe that the answers should be “epigraphic” summarising in few words the substance of the answer. Furthermore such answers should be accompanied with references to enhance knowledge as well as lengthier development that can be attached.
    A long answer, should be so well written, that you do not want to leave it before you finish. If you are a very good writer, try long answers! If you know your subject you could express it with a minimun words.

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    Dear Costas,

    I share your whish to read short and concentrated texts with the most important statements.

    And Dear Louis, inspiration is a wonderful thing, but I´m not sure that the reader develops the same feeling and enthusiasm. Therefore I always try to be short and concise.

  • Christian E. Jacob added an answer in Capacitor:
    What's the meaning of the limitation of the temperature of the capacitors?

    Usually, the datasheet of capacitors will give a limitation of temperature where the capacitors could apply, like -40℃~85℃.
    I thought 85℃ meant ambient temperature in the past several years. But today someone I know who works in a capacitor company tells me that 85℃ means the core temperature, where core means the center of capacitor.

    Then which one is right? Is it related to some standard?

    Christian E. Jacob · Max Planck Institute for Plasma Physics

    Dear Seasong,

    for roller-type capacitor in upright construction the case temperature is defined in 3/2 height of the body housing. This is valid for mostly capacitors!   

    Regards Christian

  • Anek R Sankhyan added an answer in Sharks:
    Is it possible to calculate MNI (Minimum Number of Individuals) by using fossil teeth?

    Mostly when we look shark teeth

    Anek R Sankhyan · Anthropological Survey of India

    Yes, you are right; for fish and reptiles it is a tough job- I have no working experience on them. You need to devise a formula based on extant fully preserved skulls.

  • How can I determine the right sample size to test the quality of classifiers?
    I have a very large population and 3 classifiers which perform a binary classification but still say "don't know" to certain parts of the population (the size of "don't know" outputs differs among the classifiers). The goal is to determine the quality of the classifiers, and to decide which one to take for the follow-up study. (The recall of all 3 classifiers is expected to be low, but a high precision value for both classes would be desirable.) I wanted to calculate the F1-scores but am not sure what sample sizes would be appropriate. It is quite (time-)expensive to test the classification output, so the sample size cannot be very high. Is McNemar's test appropriate here? Shall one take various samples, or change size of the sample and measure how much the performance changes depending on sample size?

    The best way is monte-carlo cross-validation. In each iteration a subset (usually 1/3) of data is run out randomly and the remainings are used for model development. The model is evaluated using the run out data. This process may be repeated for one thoushand times and the average accuracy is used as an index for measuring the quality of the classifier. 

  • Tsvetanka Babeva added an answer in Zno Thin Films:
    What might be the reason for difference in density of ZnO thin films deposited on 2 different substrates under similar conditions?

    I am using reactive dc magnetron sputtering and substrates are glass, acrylic. desity was lower on glass.

    Tsvetanka Babeva · Bulgarian Academy of Sciences

    Could you give more details about the deposited films? What is the thickness of your samples? Do they have similar morphology and structure? How did you determine the density?

  • Hossein Javadi added an answer in Modern Physics:
    Is there needs an intermediate theory to harmonize theoretical physics? If no, why? If so, how?

    My answer is yes. Because there are some unanswered questions or complex concepts in modern physics. The questions that modern physics does not have answers for, and the physicists believe that it is due to the inability of theories. So we should reconsider the relativistic Newton's second law, and to combine classical mechanics, quantum mechanics and relativity.

    Hossein Javadi · Islamic Azad University

    Dear Boguslaw

    Thank you for you interesting mentions. Let me start my comment with a quote of Max Planck, he said;"Science cannot solve the ultimate mystery of nature. And that is because, in the last analysis, we ourselves are a part of the mystery that we are trying to solve." I have accepted that there is not a complete theory in theoretical physics, and never we can provide a theory without any unanswered question. So, our trying and research is based on develop the present theories. When a theory reaches unanswered questions, it will need to develop, like the Big Bang theory that developed by inflation. There is some unanswered questions and complex concepts beyond the my question. A long years my researches show that we should reconsider the relativistic Newton's second law to solve some of unanswered questions.

  • Tim Saier added an answer in Arthroscopy:
    In patella instability with TT TG ratio 20 mm, Caton Deshamps index 1.34, trochlear dysplasia of grade 1, what should be the sequence of corrections?
    I usually perform distalization of tibial tubercle as the first procedure to correct the patella alta. If need be, I add MPFL reconstruction as the second staged procedure. I never had to add trochlear plasty.
    Tim Saier · Berufsgenossenschaftliche Unfallklinik Murnau

    I agree absolutly with Mr. Gomes. Eventually only MPFL reconstruction will be sufficient.

  • Chai Ezerzer asked a question in Nature:
    How do we account for the hidden variables in our prediction?

    "Scientific theories, of necessity, tend to interpret the evolving of nature through our senses, attempting to understand nature in terms of general principles, and searching for one theory that will explain it all – a “theory of everything”. If there is such thing as a single theory that can describe everything..." CE0702 From ENMESHED v12

  • Any who can help me in my topic for my Master thesis ... send me here or at ahmadagrarian@gmail.com

    any who can help me in my topic for my Master thesis ... send me here or at ahmadagrarian@gmail.com

  • What is your opinion/experience/reference regarding the linking power of the human person?

    +Welcome.

    The human person appears to have a linking power, which enables the person to link to the functions of another living being. Following are some attributes of these linking functions or links.

    Regarding the kind of functions the links can be made to functions of living beings, such as controlling, conceptualising, knowing, reasoning, speaking, emotion feeling, wanting, sensing (seeing, hearing, smelling, tasting, touching), moving & living.

    Regarding place the links can be made on-site or in a distance.

    Regarding time in the same or in a different time, that is past or future.

    Regarding the quantity of outgoing links multiple links can be made in the same time in pseudo-parallel using a kind of context switching between them.

    Regarding the quantity of incoming links links can be made to 1, some or all of the functions of the other being.

    Regarding the kind of the target the links can be made to the same or to a different being.

    The whole scenery in a great degree resembles & reminisces about several technological appliances & their functions, mainly computers & their networks, videoconferencing, television, telephone and others.

    The human history is full of examples of activations of these linking functions.

    The major challenge & question is how & when these linking functions are activated.

    Please share your opinion, experience or references as regards the above reasoning so that it is improved.

    Thank you.

    Giuseppe Laquidara · Independent Researcher

    Hallo.

    In short. In terms of physical tuning, linking together two or more humans beings, in particular their brains, is an established fact. Just trivially, the sophisticated technics was called BBI [brain-to-brain interface], and it is based on: ultrasounds, infrasounds and ultralow frequencies signals, emerging within some specific areas of our brains, and soliciting other's ones analog-ly.
    Linked with this phenomenon and its characteristics, you could find appropriate ways to answer to almost all the questions posed in your dilemma, but a problem might arise in case of break, physical or temporal. 
    In those cases, I could lightly suppose that two brain / meta:para-nervous behaves could attend the remote-linking functions: predictivity and equivalence/contraddictions reconstructions.
    To be deepen, of course.

    —g

  • How can I synthesis 3D graphene?

    what are the best agents to cross link between graphene sheets?

    Amin Shiralizadeh Dezfuli · University of Tehran

    I think It depends on the application. For example,I'd rather Graphene Aerogel in supercapacitors due to its facile synthesis procedure but for sensors GOFs can be better.

  • What is the relation between visual perception and stress, anxiety?

    what is the relation between visual perception and stress, anxiety? if we seeing something will get fear or stress or anxiety so, what is the mechanism visual perception causes the these effects?

  • Has any one worked on coating Carbon nanotubes with nickel by electroless deposition?

    I am working on electroless deposition of nickel on carbon nanotubes.  I am facing some problems in the process,which I am briefly mentioning  below. I would appreciate and be thankful if anyone can advice suitably.

    1. While filtering the Carbon  nanotubes after activation and rinsing stage, the filter paper (whattman filter paper in a funnel) tears when I try to scrape the dry carbon nanotubes from the paper. Is there any better method of filtering the nanotubes from the solution.?
    2. Preparation of nickel bath:    During addition of Ammonium Hydroxide (buffer solution) to the nickel bath for it to achieve a pH of around 8.2 (basic), severe salt precipitation is observed in the nickel bath, thus losing its deposition potency. How can I modify the pH of the nickel bath to basic medium without causing salt precipitation:?
    3. Also, I am carrying out the electroless nickel deposition by stirring the carbon nanotubes in the nickel bath for 30 minutes at 25 degree C. Should I carry out the process at a higher temperature (heating)?  Will heating improve the deposition rate and efficiency?

    Can anyone who has previously worked on this share their experience and references?

    Vaibhav Koushik A.V. · Atria Institute of Technology

    Dear Dr.  Alicja Stankiewicz &  Dr.Barbara Liszka,

    As you are working on nickel deposition on CNTs, I would like to know as to whether I can reuse the nickel plating bath after coating one sample of CNTs (0.25 grams), or should I prepare a fresh bath for every sample?

    If I can use the same bath for a  few successive trials, then what are the parameters I should keep a check on, other than pH of the bath to use the bath repeatedly. In specific, I would like to know as to how to keep track ( method) and measure the potency of the bath after successive trials? 

    Regards,

    Vaibhav

    P.S. : I have to prepare nickel coated CNTs in bulk quantities ( about 5 grams)

  • What are the points to be stresses in the abstract of a research article?
    The abstract is the heart of a manuscript and gives an idea about the content and conduct of the research. However, it has a word limit (often 250 words). So it is important to present your research in the abstract in the most efficient way. What are the points to be considered while preparing an abstract?
  • Mariac Cedric asked a question in Biotinylation:
    How to increase target enrichment in NGS librairies ?

    Hello,
     We prepare enriched NGS librairies by using in solution capture with biotinylated DNA probes. I would like to have your advices or return on how to improve enrichment (witch stringency during hybridization, of washes…)  in order to increase specificity and then sequencing more usefull reads.

    Thanks

  • Jochen Wilhelm added an answer in Drug Testing:
    Which is the most statistically valid method?

    In order to analyze and compare dose response relationships for a group of 4 different drugs, each drug tested on 9 separate tissue samples in vitro, what statistical test would you use? - I have an idea regarding the appropriate stats tests but would like confirmation thanks!

    Jochen Wilhelm · Justus-Liebig-Universität Gießen

    If you do not have any idea about the model and the relationship going for some "test" is the wrong way (and quite meaningless, except some pinheaded bosses or reviewers request this). It rather would be indicated to explore the relationship. The results may then serve as the information required to plan and analyze an experiment that sensibly tests a hypothesis.

    However, the key question is: what is the response/read-out? On what scale is it? (binary? ordinal? metric?) Can the EC50 / IC50 be estimated?

  • Ensieh Mosaddeghi asked a question in Inflation:
    Using logarithm of inflation rate in regression

    Hello dears,

    Can I use logarithm of inflation rate or interest rate in regression? why yes and why no?

    Thanks.

  • Jitendra Pant added an answer in Tryptophan:
    Why is tryptophan such a rare amino acid in proteins?

    i was wondering if it is to do with the phi and psi angles of tryptophan that doesn't make it favorable to be found in proteins or is it to with its high metabolic expense that it's not so common in proteins. Any suggestions?

    Jitendra Pant · BITS Pilani, Hyderabad
    • Tryptophan has a polar side chain but its side chain conformation is not energetically favored (i.e its not staggered). It has to do with the substituents on the on side chain c atom ie. C-Beta.
    • Another reason is the bulky group;  because of the ring structure, it causes steric  hindrances when it comes in contact with another bulky group in an alpha helix.
    • Overall it depends on the the protein motif ie. all alpha, all beta, alpha/beta or apha-beta whether an aminoacids can be present in a protein or not. You might like to know that apha is stabalized by local interaction while beta is stabilized by interstrand interaction. Therefore, the presence of any amino acid can't just be decided by its structure alone, it is also decided by the other amino acids around it,  which may stabilize or destabilize the over all polypeptide.
    • I suggest you to also go through the first 3 chapters of Branden and tooze. very nice and simple explanations for similar kind of doubts.
  • Debi S. Saini added an answer in Personality:
    I expect the opinion from the RG Professors regarding the unethical practices in the conference presentations.

    Dear Sir,

    Ten years back in conference presentations the presenter used to hide the identity of the diseased persons if they were showing the picture of the diseased person by covering a black patch around his eyes. This was also the practice in the medical books. In recent conferences, pictures of the diseased persons are presented without hiding the identification. Is it fair on the part of the presenter to do so?
    Dr. Shanmugasundaram P

    Debi S. Saini · Management Development Institute Gurgaon

    Dear Palani, I do not know if I have correctly understood your question. If yes, my answer is as follows: I feel that in case the dead body is from a donor, then the picture of the dead body can be shown, as it is implied that while donating her/his dead body the person had allowed its photo to be published for shown to others. If I am such a person, I have no objection to the picture of my dead body being shown. If the body came for medical use otherwise than donation by the deceased, i think then it is unethical to show its picture.

  • Michael Geoffray asked a question in Channels:
    What is exactly meant by 'age of river'? How is it possible to know the absolute age of a river?

    When someone working on geomorphology of two rivers in the same watershed wants to know the absolute age of the rivers under study, what exactly is meant by the 'age of river'? Does it mean 'age of its channel' through which the water flows (which obviously varies from head to mouth) or the age of entire valley in which the river channel is situated? or these two are the same? or something else? What are the advanced techniques to determine the age of the earth? For the sake of making the question clear, two .kmz files of two rivers, the Ganga River and the Son River of the same basin (the Ganga Basin) are attached here.