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  • Renu Balyan added an answer in Probit:
    Which type of regression model can one use when the predictors are binary and the dependent variable is non-binary?

    If you score a sentence based on the presence or absence of an error, the score is dependent on the error hence the predictor (error) is binary and the score is non-binary. Is it possible to apply some regression model in such a case. As logit and probit regression models apply to cases that are reverse of what I need. Any other method for solving the issue?  

    Renu Balyan · Indian Institute of Technology Delhi

    I think its a good idea, I was so far thinking of taking up only 6 diff experiments for each error and had not thought of going in for different models for each individual.

    If I have understood it right, I go in for 6 experiments. each for 1 error. Also for each experiment. we go in for a model for each individual with the set of evaluated sentences i.e 100 (for 1 error).

    I will try the experiments. and see how the things come out. I will check out for the methods to be used for models combining or can we go in for model selection also...?

  • Burkhard Büdel added an answer in ICH:
    Hallo Luciana,

    darf ich Dich um ein pdf Deines folgenden Artikels bitten? Zedda & Rambold 2009, The Bryologist 112(1), 19-29, Diversity and Ecology... Danke und herzlichen Gruß, Burkhard

    Burkhard Büdel · Technische Universität Kaiserslautern

    Thanks a lot! Burkhard

  • Zhihui Cheng asked a question in Rocks:
    Can the Na2O contents of volcanic rocks reflect its depth?

    What is the origin of Na2O in subduction zone? Is there any references?

  • Alexey Nikitin added an answer in Molecular Docking:
    Can molecular docking be used to screen if a particular ligand can bind anyone of several given proteins?

    I have a ligand and 5 different proteins. Is it possible to predict whether the ligand binds any of these proteins using molecular docking? If possible how? Please help. 

    Alexey Nikitin · Институт молекулярной биологии им. В.А. Энгельгардта Российской академии наук

    Since you have only one ligand, then you can make the force field for it and use conventional molecular mechanics, as a first approximation - optimization, and if you need more accuracy then the molecular dynamics or Monte Carlo.

  • Kalpita Karan added an answer in Glioma:
    Has anyone encountered a morphological change in a glioma cell line post transfection as such without any treatment?

    I visualize unusual filopodia like structures in a rat glioma cell. This is post transfection with a egfp fusion construct as well as untagged construct. This cell line has neuronal stem cell like property so I can see dendrites too.

    Kalpita Karan · Jawaharlal Nehru Centre for Advanced Scientific Research

  • Miranda Yeoh added an answer in Imagination:
    Is imagination/creativity more valuable than knowledge?

    When it comes to a debate on whether we need to emphasize imagination/creativity or knowledge in education, society, etc. how can we say that one is more valuable than the other?

    “Imagination is more important than knowledge. For knowledge is limited to all we now know and understand, while imagination embraces the entire world, and all there ever will be to know and understand.” - Albert Einstein

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

    I believe Einstein is seeing from his viewpoint and I quite agree.  Because we can't solve problems with just knowledge, imagination and creativity are more useful and needed.

  • Is there is decrease in number of neurons with aging?

    There are controversial reports about decrease in number of neurons so is it actaully happens?

    Thanks for helpful answer dr.Enzo

  • Helgi Arst added an answer in Fish:
    Why pendimethalin is mainly used for fish study?

    I had read some articles about pendimethalin, those are studied on water bodies only, 

    Helgi Arst · University of Tartu

    Fish study is not a topic of my investigations

  • Nane Kratzke added an answer in Cloud Computing:
    Can some body help me in variable workload prediction and estimation in cloud computing?

    what are the heuristics to estimate the workload?

    Nane Kratzke · Luebeck University of Applied Sciences

    You may want to check several of my publications dealing with that question in a broader context of cost estimation.

    I also found the "mathematical proof of the inevitability of cloud computing" by Weinman very interesting. It shows that in most cases it is sufficient to do estimations about peak loads.

  • L. Gaikwad added an answer in Trust:
    How can the trust factor be managed in these cases?

    There are sometimes no choices, but to disclose the protected process or product knowledge to the suppliers. How can we handle it to keep the critical info. away from the competitors?

    L. Gaikwad · Bharati Vidyapeeth college of Engineering, NaviMumbai

    In Qualitative the thrust factor should be consider for supplier selection but how for new supplier?

  • What are the factors to consider in material simulation for dental application?

    I intend carrying out a laboratory experimentation of a produced dental material.

  • James F Peters added an answer in Camouflage:
    How to measure the level of camouflage?

    I have a set of photos of birds and I wish to create an index on how well they blend into the background or in other words how much their colour and pattern deviates from their background. Is there some tools, that doesn't require source code and programming language, which could be useful for this task?

    I have attached an example photo. I added one without the bird and one with the bird for comparision (for all the photos I have picture with and without the bird).

    James F Peters · University of Manitoba

    Dear Lambert,

    I agree with you that the question for this thread merits many more observations and discussion.   For example, Ronny Steen has made a good observation about those birds that are sometimes taken by surprise when they are on the ground.   That probably happens due to the need to search for food.   And, no matter how well camouflage a bird is when it is not in motion, such a bird will reveal itself (for some eyes such as other birds or hawks) whenever it starts moving.    I am guessing that the reason this thread and many other threads have gone quiet is due to the holidays.

  • Mahdi Lotfi Panah added an answer in Bibliometrics:
    How do you get whole Scopus data?
    I want do a bibliometric analysis and dont know how to get bibliographical information of Scopus, where the affiliation is included, or the country of every author. Thanks
    Mahdi Lotfi Panah · Tehran University of Medical Sciences

    choose document search and then affiliation name, city or country.

  • Behrouz Ahmadi-Nedushan added an answer in Blogs:
    Do there exists corrupted scientists?

    We see and hear a lot of things about "corrupted Science". In RG we have,

    Mehdi Rajabi Asadabadi · 2.40 · University of San Jose-Recoletos
    Some of these agents offer ISI publication coauthorship with 3000 US$.!

    I have seen in net that they are selling Masters and PhD's!

    Top 50 Psychiatrists Paid by Pharmaceutical Companies

    Science is being corrupted to a point of fraud

    Behrouz Ahmadi-Nedushan · University of Yazd

    Definitely yes. There are Corporations which Corrupt Science at the Public's Expense

    I found 2 cites which deals with corruptions in science


    There is also the Union of Concerned Scientists (UCS) which  released a report in Feb. 2012

    The UCS summary report concisely details these methods. For example, under Corrupting the Science, the report notes five ways that corporations use their influence:
    1] Terminating and suppressing research (corporations often end research or withhold unfavorable results)
    2] Intimidating or coercing scientists (Scientists and academic institution are often harassed into silence through threats of litigation and loss of jobs/contracts).
    3] Manipulating study designs and research protocols (using flawed or biased methodologies in their testing and research)
    4] Ghostwriting scientific articles (corrupting the integrity of scientific journals by “planting” ghostwritten articles that actually promote their products).
    5] Publication bias (selectively publishing positive results and burying or under-reporting negative results)


  • Alexander V. Ilyin added an answer in Publication:
    If a researcher publishes some results in English, and then a part of them in other language, should it be treated as two publications?

    Is there a rule that a title of the second publication should be ended with something like "Translation of the <Title of the 1st publication>, shortened form"?

    What about full translation?

    What if a couple of new sentences are added in the second publication?

    Alexander V. Ilyin · Russian Academy of Sciences

    Dear colleagues, thank you for sharing your opinion! Special thanks for useful links, @Ljubomir, @Behrouz, @Abedallah.

  • Rita De Vuyst added an answer in Physics:
    Can we mathematically model consciousness?
    We have seen that AI, which was supposed to be a failure, is coming back with
    gusto on the back of multi sensor robotics and possibly androids with quantum computers. There is some mysterious counter intuitive behaviour in the sub atomic world which seems to suggest inanimate objects do sense the external world.
    It would be nice to know the views of experts from different fields, such as math, science, psychology, sociology, cosmology on this intriguing subject. One possibility
    that comes to mind is if probability is actually such a model, as it does incorporate
    Rita De Vuyst · Afkikker/Klimop

    Indeed most questions are hard to answer, although every day many are bending over. Riddles are very attractive.

    The marriage of science with the thinkers of 250 years ago is an unspoken monogamous  bond which keeps the structure together in the fight against the entropy, the holy grail of the second law.

    The philosophy of the physicists of the 20th century sounds as broken down.

    The effort of individual researchers in the field can’t be neglected, nobody can mention all their names. But they succeed in expressing the mystery of life in the hope one day everything will be unified in one single formula of Love.

    It is  Eros which can’t be find, who has to bind all the bricks together to contemplate the building. And what is not proved does not exist.

    But the sheet music of  composers as Bach, Ysaye, Paganini, Mal Waldron are they not a pure mathematical formula of pure consciousness which even can be reconstructed in time. And is this not the prove of negentropy originated by the Italian mathematician Luigi Fantappie.

    The higher the consciousness the purer the line which can be re-incarnated.

    The composer, the musician, the receptor, the muse, the acousitcs, the place are one in a timeless intuitive point vibrating in a cosmic erotic field probably dominated by the coupling constant as recognisable in the story of Pauli (the whole story is for later).

    Yesterday we had a concert dedicated to the 102nd birthday of Johan Daisne. The whole city of Ghent, as the home town of Daisne, was invited. There were 13 people, 4 tourists included, as the title of his book ‘With 13 at the table’.(mention the archetype)

    And someone wrote in the book of Afkikker:

    Being god, Misha (Mikhail Bezverkhni) surpassed himself.

    Something that never will be forgotten.

  • Roland Iosif Moraru added an answer:
    What is the difference between ratio and proportion?

    They always come together.

    Roland Iosif Moraru · University of Petrosani

    Dear Dr. Costas

    Excellent document, what you have attached.

    Dr. Mahfuz, I am a big fan of your brief answers and I make a point to read all related to questions of my interest.

    Dear Eddie,

    Proportions are built from ratios. A "ratio" is just a comparison between two different things. For instance, someone can look at a group of people, count noses, and refer to the "ratio of men to women" in the group. Suppose there are thirty-five people, fifteen of whom are men. Then the ratio of men to women is 15 to 20.

    Notice that, in the expression "the ratio of men to women", "men" came first. 

  • Maziar Mehrabi added an answer in Computer Vision:
    How can i receive visual light communication (VLC) by cam using image processing?
    I wanna receive data sending it by VLC using android app for smart phone
    i use a bulb led to do that ,I have atmega32 to send data by 60 HZ as the screen do
    but the cam i use 30 FPS . to make the change invisible from human it must be in range 60 fps -50 fps
    so my problem now is how to do that ??!!!
    Maziar Mehrabi · Åbo Akademi University

    Can you please give more information about the LED you are using? Such as brand and model.

  • Kai Robinson asked a question in Airway Management:
    Much needed research regarding basic v's advanced airways in OHCA

    An excellent protocol that will hopefully extract enough knowledge to influence airway management in OHCA by Paramedics

  • Béatrice Ewalds-Kvist added an answer in EIT:
    How likely is bubble contrast given to detect intracardiac shunt during echo to cause stroke?

    Bubble contrast during echo as an eit ology for iatrogenic stroke

    Béatrice Ewalds-Kvist · Stockholm University

    A doctor is not a good doctor before he has filled one graveyard:)

  • Christoph Kerzig added an answer in TCSPC:
    Can somebody suggest an ultra short fluorescence lifetime standard which absorbs light at 440 nm?

    I am using a Beckr and Hickl Tau 130 TCSPC setup for fluorescence lifetime measurement of different fluorophores. For excitation, I am using a pulsed laser (440 nm). For now, I am using fluorescein dianion as my standard but I would like to try other standards as well just to see if my TCSPC setup is giving right results. So, I am looking for a fluorophore which absorbs light at 440 nm and have a stable lifetime. Thank you!

    Christoph Kerzig · Martin Luther University of Halle-Wittenberg

    Both fluorophores absorb light up to 600 nm; attached is the UV-Vis spectrum of Erythrosin (taken from: DOI: 10.1007/s00706-010-0414-1, Rose Bengal absorbs really similar)

    Best of luck,

  • Maulick Chopra asked a question in Toxicity Studies:
    How do we finalised the dose range of Curcurmin for In-vitro cell toxicity studies (IC 50)

    I prepared curcurmin polymeric nanoparticles. Now want to do In-vitro cell toxicity studies (IC 50).
    In the reported paper the dose range of curcrumin in albino rat is 20 mg/Kg. And in human the dose range is 900 mg. So, for In-vitro cell toxicities studies, how can we select the dose range of curcurmin.

  • Sherlock Chu asked a question in Fabrication:
    Can anyone tell me how to attach 5-ALA on gold nanoparticles ? Or how to synthesised cationic gold nano particles?

    Our lab is now facing a problem on how to synthesised cationic Gold nano particles. 

    We established our own method to fabricate Gold nanorings by on substrate fabrication instead of chemical synthesis. We aim to combine PDT with PTT. So the first problem is to attach 5-ALA on gold nanorings. With the negatively charge surface ALA molecules, the most direct way to attach ALA on gold nano particles(GNR) is making a positively surface charge GNR. But most of the previous research synthesised cationic GNR by adding HAuCl4 and BPEI together to generate a cationic molecules. But we use different way to fabricate GNR. Therefore can anyone tell me how to synthesised cationic GNPs to attach on ALA?

  • Why So Few? Women in Science, Technology, Engineering, and Mathematics

    Please, the following link related to the subject:


    The number of women in science and engineering is growing, yet men continue to outnumber women, especially at the upper levels of these professions. In elementary, middle, and high school, girls and boys take math and science courses in roughly equal numbers, and about as many girls as boys leave high school prepared to pursue science and engineering majors in college. Yet fewer women than men pursue these majors.

    By graduation, men outnumber women in nearly every science and engineering field, and in some, such as physics, engineering, and computer science, the difference is dramatic, with women earning only 20 percent of bachelor’s degrees. Women’s representation in science and engineering declines further at the graduate level and yet again in the transition to the workplace.

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

    There are few women in the T and E of STEM, at least in US and in Malaysia.  Women tend to do better in life sciences.  This is unusual because females did better than boys in school, and have a majority of places in university.  But in  Technology and Engineering, the number of women is small.  To encourage women, scholarships are provided.  Furthermore, a significant number of undergads in US failed to graduate after 6 years in varsity.  This is why I'm currently doing research in motivation for STEM education.

  • Chris Jeynes added an answer in Genesis:
    When were the Creation accounts in Genesis 1 & 2 composed, and who by?

    I am reading Mark Smith's "The Priestly Vision of Genesis 1" (2010) and finding it very frustrating.  He is so convinced that P wrote the account in the 6th century he doesn't bother to tell us why he is so sure.  I am not much disposed to believe in P, J  JE, RJE etc etc considering the fiasco that is the story of Q.  What is the evidence?  Note that I say "composed",  not "written"?  One issue is the canonical text and its editor.  Another issue is the set of sources the editor used.  A third issue of great importance is how the editor used his sources,  and what creative freedom he allowed himself.

    Chris Jeynes · University of Surrey

    William:  it really is chapter and verse I am interested in.  Opinion is abundant,  but opinion closely argued from the texts is much rarer.

    I suspect that the texts are both more reliable and remember older events than they are usually credited for.  Bear in mind that complex events are simplified in such accounts as these;  probably heavily simplified.  But the way the texts are written deliberately leaves traces of the simplification so that the underlying complexity is still (faintly) visible.  Why for example does Kipporah say to Moses "Surely a bridegroom of blood art thou to me" (Ex.4:25;  a text still heavily debated).

    600,000 "men" (plus children: what about women?) is mentioned at Ex.12:37.  This number is large,  but is easily generated by 4 surviving (and breeding) children per family and a generation time of 30 years.  We know that there have "always" been Jews (Israelites) in Egypt,  so it may well have been that the number was actually fluid with large numbers at certain events with many "visitors" from the region (including both Canaan and Egypt).  But the accounts themselves must have originated from the time in question to have had any authority.

    Throughout the Torah the Hebrew (Masoretic) text of the Jewish Publication Society has many footnotes: "meaning uncertain".  These are of individual words,  of clauses,  of sentences and of passages.  The text itself is almost entirely unequivocal,  but the meaning of the text is often simply uncertain,  and even where the individual words and grammar are well understood the text may be ambiguous.  To me this speaks of an ancient text faithfully preserved.  But the usage of words changes over time so that where the text is certain the meaning may not now be.  Moreover,  the original authors were themselves subtle;  they expressed themselves often exceptionally briefly,  and,  we have to assume,  intending the remaining ambiguities.  Their confidence bespeaks authority. 

  • Rene Krawczynski added an answer in Grazing:
    Does anyone know if and which vertebrate herbivores will eat Spirea sp. without being violently forced or starving?

    I am working on an article on neophytes and grazing in Germany. Does anyone know if and which vertebrate herbivores will eat Spirea sp. without being violently forced or starving? Cattle, horses, roe deer, red deer and moose seem to avoid it and sheep or goat need to be forced. Maybe someone has experience from its native area in North America?

    Rene Krawczynski · Brandenburgische Technische Universität Cottbus

    Thanks for the information. We are in Lusatia, so according to the article in the center of Spiraea tomentosa population.

  • Frank Veroustraete added an answer in Yaws:
    What is the best way to determine the Yaw angle rate and the Yaw angle for a LEO/SSO satellite?

    I want to develop an easy algorithm to get these values based on TM and also to determine the theoretical values of the Yaw and Yaw angular rate to compare to those that came from TM.

    Frank Veroustraete · University of Antwerp

    What about star tracking data?


  • Jerome Polesel added an answer in Sol-Gel:
    How can I coat alumina micrometer particles with a silica layer ?

    I'm looking for a simple recipe to coat particles of alumina (100 micrometers of diameter) with a silica layer (1 micrometer thick). I need to produce one kilogram of powder of alumina/silica coated particles. I thought about sol-gel procedures, but which one would be the best ? Are there other ways ?

    Jerome Polesel · CEA - Atomic Energy and Alternative Energies Commission

    Dear all,

    Thank you very much for your suggestions, they are very helpful.

  • Murali Arthanari added an answer in Field Crops:
    Does anyone knows the antidote for glyphosate, paraquat and 2,4 -D herbicides in plants?

    The herbicides are knowingly or unknowingly sprayed by the farmers in the field crops caused plant injury. This situation has to be recovered and the crops should be saved. What is the recommended antidote for the above herbicides. If anyone knows please tell me with references.

    Murali Arthanari · Tamil Nadu Agricultural University

    Dear Frank.

    Thank you very much for your informative answer. Its really gives  the fact that, these herbicide are unable to manage if farmers are unknowingly sprayed. Anyhow, we have to find suitable antidote for these herbicides to save the crops. Since, most of the farms, this is a herbicide problems are noticed frequently, as a scientist i am not able to answer for this situation. The farmers who cultivate good crop is suffering because of these herbicides due to some reasons.

    My question is that, is it possible to discover a new antidote for these  herbicides. If its so, anybody attempted? Let me discuss further in the next mail


    Murali Arthanari

  • Francesco Roselli added an answer in Lipofectamine:
    SH-Sy5y transfection reagent


    I would like to transiently transfect SHSY5Y cells. I know they are not very easy transfect and I read one article where they used Lipofectamine 2000 but on invitrogen protocol pages I did not see any information for SHSY5Y cell transfection. anybody has an experience? and maybe protocol?

    Francesco Roselli · Friedrich Miescher Institute for Biomedical Research

    I have  experience with shy and sk-y cells. I had good results using freshly passed cells (the night before) and Jet-PEI polyplus transfection reagent, which has the advantage of being serum and antibiotics compatible. Usually the efficiency is around 30-50% (sometimes higher) which is suitable for most biochemical applications.