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  • Douglas R. Daugherty added an answer in Teaching:
    Could we teach anything else than subject matter anyway?

    Teaching is teaching something: that is mostly subject matter, a disciplinary content or whatever other content. The key word here is content. What else?
    Many people believe this. What’s your opinion?  

    Douglas R. Daugherty · University of New Mexico


    In this case I must say my meaning was not made clear at all. I am not a positivist at all.In fact I am in many ways a person who argues from the same position as you. 

    This notion of objective knowledge may be true in the physical or natural world but in the social "the method" cannot be used as a "truth" meter fro several reasons. The least of which is the social world is not governed by "natural laws" such as E=mc2 or displacement forces such as wind shere.

    The social wolrd is abstraction, are the issues debated by Socrates, Plato, Aristotle, and the Cave of Alagory, within the Garden of the imagination. Yes, JC. in the end knowledge can be both "truth" as being argued on another thread but knowledge is also subjective in the sense of what is chosen as knowledge. This is the point I am trying to make and defend.

    Is knowledge not used really knowledge? Or is the theory of social reproduction, social capitial, instutionalism, any less a "knowledge" that 2+2=4. I say no. I also say that to think in such a way as 2+2=4 is knowledge but education as an oppresive tool is Doxa is insulting. It limits the potentional of new paradigms, new avenues of science, and new epistemolgies.

    I aslo agree with you this stance is not depressing, it is freeing, liberating, and creative. It allows for the continuged dialogue concerning what is justice to continue, inclusion, and equity also.

    I hope I have made my point clear now.

    All coments are welcome,


  • Zulkarnain Sinor added an answer in Saliva:
    Does the salivary flow rate in children differs from the rate in adults?

    When recording unstimulated salivary flow rate, we consider 0.3-0.4 ml/min as regular and less than 0.1 ml/min as oligosialia. These values are measured for adults. Shall we use those values also for children? I could not identify any paper or recommendation regarding the evaluation of the salivary flow rate in children with other values than for adults. Is the normal salivary flow rate constant over the ages?

    Zulkarnain Sinor · University of Science Malaysia

    if diagnose as one of the sign of Oligosialia, yes; but as Oligosialia per-se ,no.

  • Mohamed El Naschie added an answer in Group Algebra:
    What is the physical meaning of cummutative group algebra and non cummutative group algebra?

    Several times we come across in particle physics that for commutative groups mass gap problem is not there but it exists for non commutative group algebra. Does the introduction of non commutative algebra is requirement of symmetry breaking?

    Also I want to know that What is the physical need of lie groups in particle physics.

    Mohamed El Naschie · Alexandria University

    already  as a school boy werner Heisenberg thought about symmetry and was stimulated by TOMAYAS.  without SU3  we could not understand quarks.without E8E8 or SO32 we have no superstrings and so on. 

  • Karolina Simat asked a question in Corporate Ethics:
    Is there any efficient measurement tool of CSR in travel agencies?

    I am going to write my PhD thesis on corporate social responsibility in tourism context. More precisely, I would like to investigate corporate ethical values and the perceived importance of ethics and social responsibility of employees in travel agencies as well as what CSR behaviors are exhibited by travel agencies in a developing economy (in Serbia).
    Could you please advise me an efficient measurement tool?
    Any reference will be helpfull. Thanks.

  • How can I calculate the derivative of a matrix and the nth root of a matrix ?

    Any suggestion/resources are appreciated.

    Jose Luis Ramirez · Universidad de Carabobo, UC

    Using Newton's Method applied to X^p=A you can obtain good solutions, also can use another iteratives methods developed  to ensure stability.

  • Azimun Nahar added an answer in Food Biochemistry:
    How can I prevent fungal growth in orange juice after inoculating E. coli O104 to see the BVNC state?

    I want to see the VBNC state of E. coli O104 and O157 in orange juice. I inoculated  those bacteria in orange juice but after certain time I found so much fungal growth in inoculated range juice. So, how I can prevent these fungal growth in those inoculated orange juice? If anybody know about that, please answer me.

    Azimun Nahar · Bangladesh Agricultural University

    Thanks all for suggestions.

  • Freek Geeris added an answer in Calcaneus:
    Do you think the structural twist in the posterior aspect of the calcaneus can be used to trace the hominin lineage?

    Ernst Haeckel’ss adage ‘ontogeny recapitulates phylogeny’ envelopes the concept that the developing embryo goes through stages resembling successive stages in the evolution of their extinct ancestors.

    Haeckel’s adage, which has been largely rejected as a biological hypothesis, differs from the hypothesis I suggest which could trace the direct lineage of hominins. I have termed this hypothesis the Ontogeny –Pylogeny Evolution Model. In retrospect, a better name would be the Ontogeny Phlogeny Calcaneal Model (OPCM) which suggests that all hominid ancestors (e.g., progenitor) will exhibit the same structural twist (Supinatus) in the posterior aspect of the calcaneus.

    Apply the OPCM to uncovered fossils in the hominin taxa would eliminate Australopithecus africanus as a species in the human lineage.

    Your thoughts?

    Freek Geeris · Mars Photo Imaging

    Time to get the word out on this. There might be others in your field who have come to a similar conclusion, and would like to work on this together. It might only need a few clicks to find them.

  • Shelley Minteer added an answer in Amperometry:
    How do you use an Ag/AgCl reference electrode for amperometry?

    Is it necessary to have the Ag wire dipped into a KCl solution during using it as a reference electrode? Or can I just use the Ag wire having a layer of Chloride on it?

    Shelley Minteer · University of Utah

    However, be careful if using a biological buffer like Tris, because it reacts and then this reference electrode isn't at a stable potential. 

  • Hossam Donya asked a question in Neutron Irradiation:
    Why radioactive rare earth elements are formed after neutron irradiation to B-based crystal ?

    Surprise? I have one question, in my experiment of long-time irradiation (4hr) to some B-based polycrystal to high flux neutron beam in the reactor, I have found rare earth radioactive material appeared gamma spectra of Ge gamma detector such as Ta-182 and Eu in addition to Cs-134 and Fe-59. The irradiated material does not include any rare earth

  • Mohamed El Naschie added an answer in Fractals:
    Are all Wada basin boundaries fractal?

    A point X on the basin boundary is a Wada point, if every open neighborhood of X has a nonempty intersection with at least three different basins. The boundary of a basin is called Wada basin boundary.

    Nusse, H.E., Yorke, J. A.: Wada basin boundaries and basin cells. Physica D 90, 242 -261(1996)

    Mohamed El Naschie · Alexandria University

    wada basin is example for a geometry with wild topology.this the topology of high energy physics and E-infinity physics. lik Alexander horns it ramefais into a cator set worth of wild points

  • Which are the different membranes utilised in microbial fuel cells? Which membrane is suitable for electrochemistry studies in small laboratory?

     Various artificial membranes and natural membranes that can be used for electrochemistry studies ?

    Shelley Minteer · University of Utah

    Or Celgard which is a cheap battery separator

  • Nuno Rosa added an answer in Spermatogenesis:
    What is the difference between two proteins Sam68 and p68(DDX5) ?

    Also, if they are different what is known about them in spermatogenesis.

    Nuno Rosa · Universidade Católica Portuguesa

    In Uniprot they appear as two different proteins:

    Sam68: http://www.uniprot.org/uniprot/Q07666

    p68 (DDX5): http://www.uniprot.org/uniprot/P17844

    Sam68 have p68 as an alternative name but don't result from the translation of DDX5 gene. 

    From the alignment of the two proteins we can see that they are structurally very different:


  • What is the best method for permeabilising cells?

    Currently i have been using 90% ice cold methanol and incubating either on ice for 30 minutes or at -80 degrees for a few days. I need to permeabilise my cells for an intracellular phospho staining and so far I'm not getting a very good signal at all. I know there a multiple methods for permeabilisation and i just want to know some other methods i can try that someone has personally  andused had success with.

    Thank you in advance!

    Kyal Anthony Young · Monash University (Australia)

    Thank you all for your replies.

    I am going to give the Triton, Tween and definitely Saponin a try!

  • Learned net avoidance in fish?

    I am interest if anyone has attempted to quantify, or has any evidence that fish can become accustomed to nets and 'learn' to avoid capture when sampling is undertaken at high temporal resolution (e.g. weekly).  My interest is related to field-based monitoring programs in 'closed' (e.g. river pools, wetlands) or small freshwater systems involving regular, intense sampling programs (e.g. weekly/fortnightly).

  • Sebastian Zlotnik added an answer in Spin Coating:
    Is there any efficient way to spin coat GQD solution (GQD in DI water) on quartz. ?

    I've increased the GQD concentration by centrifugation and spin coated on quartz at 2000 rpm for 60 second. But I did not obtain uniform coated surface.

    Sebastian Zlotnik · University of Aveiro


    Other way is to treat substrate (quartz) in order to functionalize the surface to improve wetting. Try initially to clean the substrate in simple H2O2.

    All the best!!

  • Andrew Limantol added an answer in Temperature:
    Could anyone help me with a tool (suggest any effective method) that could be used to assess changes in rainfall variability over a period of time?

    I conducted a survey to assess farmers' perception on climate change and found out that their views on temperature were true on analysis of observed temperature data but views on rainfall were difficult to assess with observed rainfall data. While they think rainfall amount had decreases over the past study period, analysis of rainfall trend does not prove so. I therefore think that, apart from possible increasing trend of PET due to increasing temperature, possible increasing trend in rainfall variability over the period could account for their perception. Hence, I wish to assess rainfall variability trend over the study period.

    Thanks in advance.

    Andrew Limantol · University of Abomey-Calavi

    I am most grateful to you all for your invaluable ideas and concern.

  • Zubair Shah added an answer in Algorithms:
    What is the update cost of Lossy Counting per element?

    Can any one explains to me that what is the update cost of Lossy counting per element.

    Zubair Shah · University of New South Wales

    Lossy Counting is famous algorithm for constructing summary from streams. And yes it is a sort of sketching algorithm, however, unlike count-min sketch lossy counting is deterministic rather than randomized. In the original paper (ref given below) I couldn't find the update cost per element.

    Manku, Gurmeet Singh, and Rajeev Motwani. "Approximate frequency counts over data streams." Proceedings of the 28th international conference on Very Large Data Bases. VLDB Endowment, 2002.

  • John Macken added an answer in Transfer:
    Why does a photon transfer all its energy to an electron (and disappears) rather than transferring part of its energy and continuing to exist?

    The photon CAN transfer part of its energy to the electron and continue to exist. An example of this is Compton scattering, where a gamma ray transfers enough energy to the electron to ionize and move it out of the atom's potential well, but my question is about electronic transitions in the visible spectrum.

    John Macken · Saint Mary's College of California

    Nabeel:    I will elaborate on my previous answer and address the fact that a photon transfers part of its energy in Compton scattering. Even when a photon is reflected from a "moving" mirror, the energy of the reflected photon changes (Doppler shift). Therefore, these are two cases that demonstrate that photons do not possess quantized energy. It is angular momentum that is quantized, not energy. When a photon is emitted or absorbed, it transfers ħ of angular momentum and the associated energy is also transferred.

    Compton scattering is usually considered to be proof that photons have particle properties. However, Schrodinger analyzed this in a 1927 paper and showed that Compton scattering has a purely wave-based explanation. Starting on page 10-24 of my online book (available at the link below) I analyze both Schrodinger's explanation and then expand on this using my spacetime model of the universe. The energy transfer between the photon and the electron does not involve the transfer of quantized angular momentum, therefore only part of the photon’s energy can be transferred. The amazing part is that the wave-based explanation of Compton scattering is actually better than the particle-based explanation because the wave-based model explains how it is possible for an electron to undergo a discontinuous change in velocity in Compton scattering without accelerating through intermediate velocities.

  • 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.

    David Charles Wright-Carr · Universidad de Guanajuato

    This has at times been a fascinating thread, but I think it is running out of steam and is going off on tangents, so I shall say goodbye, thanking you all for sharing your thoughts.

    Best regards,


  • How many different angles between lattice planes {hkl} exist?

    Is the number of possible angles between symmetry-equivalent lattice planes {hkl} predictable, or do I have to generate them all and calculate the angles for each pair? I assume it is a property of the metric tensor (and the implemented lattice symmetry).

    Tarik Ömer Oğurtani · Middle East Technical University

    Dear Gert,   finally  after reading your last comments I have anticipated that you are interested in the number of distinct angles formed as a subset of the whole possible angles formed  out of the given set  of {hkl}  planes of form. I was only trying to  figure out that number for the cubic system first. 

    We should not forget the plane of form is defined as a group of planes which are connected by the symmetry elements (operations) associated for a given lattice system that determined by the minimum symmetry elements.   That means hkl set also includes negative counter parts of   hkl for cubic systems,  hk only for the tetragonal sistem, etc. Also I know that reciprocal lattice of  FCC  is  BCC or visa versa.

    Looking the reciprocal lattice, one can easily see that   (110) :101 =60, (110 ):(-110)=90;  (110): (-101)=120;  (110):(-1-10)=180  EQD  etc.

  • Alfredo Pereira Junior added an answer in Qualia:
    How to define human consciousness?

    After many years of discussion of the concept of human consciousness, I arrived to the following definition:

    “Conscious processes are qualitative experiences that contain at least four kinds of ingredient:

    a) Sensations and feelings (such as hunger, thirst, happiness, sadness, fear, pain, pleasure);

    b) Perceptual qualities or ‘qualia’ (such as colors, sounds, smells, tastes, etc.);

    c) Cognitive processes grounded on feelings and ‘qualia’, such as attention, thinking, memory formation and recall, etc. and

    d) A spatiotemporal structure, composed of an egocentric spatial framework (according to the work of Arnold Trehub) and a temporal duration of (conscious) episodes of 100 milliseconds to 3 seconds (according to the work of Ernst Poppel)”.

    This definition does not include the controversial concepts of “Self” and “Free Will”.

    I basically agree with David Hume and Thomas Metzinger that the concept of Self is a product of conscious activity, not a metaphysical soul to be considered as a pre-requisite for the definition of consciousness. What is implied by the above definition is the existence of a body that is the bearer of experiences, and also is affected by them. In this sense, the definition is close to the phenomenology of Maurice Merleau-Ponty.

    The feeling of will is relevant for conscious activity, but the possibility - raised by Immanuel Kant - of initiating a totally new causal chain in the world, besides probably being an illusion, is not an essential ingredient of the concept of consciousness.

    The effect of conscious activity on the body (and vice-versa) cannot be explained in terms of Aristotelian “efficient causation” (since it violates the “causal closure” of the world, as pointed by Jaegwon Kim – see link below), but can be understood in terms of “formal causation”, in the sense that the form of body activity can affect the form of conscious activity, and the form of conscious activity can affect the form of body activity.

    Alfredo Pereira Junior · São Paulo State University

    Dear Carlos, in the context of Cartesian Dualism (Substance Dualism) neither the environment not the body are essential to consciousness (conceived by Descartes as "thinking of thinking"). However, his "dream argument" against naive empiricism is sound, even for those like me who do not accept Substance Dualism. The sensory presence of objects is not necessary for the formation of conscious states. The brain can create conscious episodes from previously internalized information patterns.

    Phenomenology begins with Descartes, but has a turning point in the late phase of Husserl, when the assumption of interaction with the "world of life"(Lebenswelt) was made explicit in his argument against Descartes (in the book "Cartesian Meditations"). 

    If we agree that the starting point for any approach - philosophical or scientific - to consciousness is phenomenological, then we are assuming some kind of interaction between the conscious system (including its body) and the environment. For existential phenomenology (as in Merleau-Ponty) the perceptual process is the primary source for understanding consciousness, and the interaction with the environment is pre-reflexive as you wrote before. However, the conclusion seems to be that environmental information patterns are relevant to consciousness only if they are registered and felt by the conscious system. Otherwise, they remain unconscious.

  • Douglas R. Daugherty added an answer in Parenting:
    Does anyone have recommendations for parameters' correlation with aggression?

    I'm trying to create a theme, where aggression correlated with other phenomena, but it must have a pedagogical aim. I was thinking about relationship between parenting style and aggression, but this theme is psychological. Any recommendations for theme that will have pedagogical aim (theme has to be from pedagogy)?

    Douglas R. Daugherty · University of New Mexico

    As I have with the few down votes I get. Would the person who down voted my response please be kind enough to explain why. I would love to know the reason and engage in a discussion, further explain my response or at least know where to put the reason.

    Thank you,


  • Is histone ChIP-Seq possible with muscle samples that have been snap frozen right away?

    Hi Guys, I want to conduct ChIP-Seq for a couple histone modifications from muscle tissue. The samples that I would work from were snap frozen right away (ie no crosslinking step was applied to the samples before they were frozen). Can ChIP-Seq still be done with these samples, despite the fact that crosslinking was not done right away?

    I have also read that native chromatin prepared by nuclease digestion (NChIP) is better for studying histone modifications anyway because they are already tightly associated with DNA. NChIP avoids the crosslinking step, which is advantageous because antibodies can identify the specific modifications better/more readily than ones that undergo a crosslinking step.

    Can NChIP be done with my already frozen muscle samples? For my purposes, would NChIP be better than doing a crosslinking ChIP procedure?



    Oleg Laptenko · Columbia University

    It will work but.... Crosslinking chromatin with FA will preserve chromatin architecture especially within those regions where nucleosomes are not strongly positioned. Therefore, I would take the results of such ChIp seq with some caution. ChiP under native conditions shows greater variability than ChiP done on X-linked material. Therefore, it should be done in parallel on several independent probes (some people do on 4-5). Variations in MNase digestions (from sample to sample) may also introduce significant bias. As ChIP seq is a costly procedure that takes significant time and effort it should be carefully planned.

    Good luck

  • Qingsong Zhu asked a question in Drugs:
    Can someone propose a list of drugs (>=5 drugs) which target the same target?

    Can someone propose a list of drugs (>=5 drugs) which target the same target?

    Thank you very much!

  • Helena Janik added an answer in DMSO:
    How does solvent affect on the molecular weight of polymer?

     I mean how  can The polarity of the solvent effect on the molecular weight of synthetic polymers is based on the condensation reaction?" between DMAC & DMSO which one increases the molecular weight"?

    Helena Janik · Gdansk University of Technology

    I do not understand any questions or answers as they are not precise. What kind of polymer do you have? linear, branched or crosslinked. What do you mean "alter the molecular weight in solvent?" The chainsare chnging the entropy in the solvent not molecular weight. In case your solvent will react with the polymer-then you will change the molecular mass.


  • What is the recent modern and advanced treatment of pancreatic cancer?

    Surgical management.

  • Jim Jackson added an answer in Sarcopenia:
    Calf circumference as a surrogate marker of muscle mass for diagnosing sarcopenia in Japanese men and women ?

    please assist in sending me this journal

    Jim Jackson · London Metropolitan University

    Apologies Doria for misspelling your name.

    Many thanks, once again.


  • Helena Janik added an answer in Polyurethane:
    Can we refer the cross-linking of polyurethane as vulcanization?

    Thanks in advance for your replies.

    Helena Janik · Gdansk University of Technology

    I think that we should be precize in science and I agree to some extend with Gyorgy that vulcanization is the proper therm if we are obtainig elastomer but in my point of view it is limited to rubber after adding sulphur. This is true vulcanazation and it is historical point of view. Then more generally, vulcanization belongs to the processes called cross-linking. So taking into account the history, vulcanization was the first example of crosslinking, otherwords, the obtaining of networks of polymers. But it is not neccessary to use sulphur to crosslink polymer, rubber, cautchouc.

    In case of polyurethanes we should  use the term cross-linking. There are many reactions leading to cross-linking of polyuretahnes. Please send me your mail and I will send you my  chapter 9, Thermo and Chemoset Polyurethanes or you can find it in Handbook of Thermoset Plastics by Dodiuk and Goodman.



  • Should the whole class be graded for collaborative team effort along with individual performance?

    In recent times interpersonal skills such as working in a team seems important for success.If so, should problems / assignments be set , which cannot be answered by one or two individuals but which would require a collaborative effort of many individuals.Student grades with class collaborative grade would give a measure of how the group as a whole may succeed in life. This may explain why some batches seem to perform better than others. This may be more relevant in Engineering, Business , Computer Science than in Mathematics or Art. It would be interesting to know if there are any research results on this.

    Yanqing Wang · Harbin Institute of Technology

    This is a very interesting topic. We have done a research http://arxiv.org/abs/1401.6244

    It has not got published, but it may be helpful to you.

  • Stephen Warren added an answer in Space Time:
    Is the flow of time an illusion?
    This has been discussed on ResearchGate in a rather ad hoc way in relation to another question about the absolute immutability of some physical laws but it really deserves its own separate discussion. Below I summarise the arguments in favour.
    The philosophers
    The nature of time has been the subject of discussion by philosophers for 2000 years or more. In the last two decades their views have crystallised. If time flows - (1) How do we know? and (2) How do we measure its speed? In other words - what frame of reference can we use to measure time?
    The philosophers' conclusion is that they would have to invent another time dimension for the purpose but this would then need a third time dimension and so on ad infinitum. This would be absurd and so they conclude that the flow of time is an illusion.
    Relativity, Einstein and Godel (A World Without Time - Palle Yourgrau - Penguin Books, 2005)
    According to the theories of relativity two observers can never agree on the simultaneity of two events that both witness and neither has a "preferred" position that makes one of them correct. This implies that all events already exist and that what we perceive as the flow of time is an illusion.
    Godel showed that rotating universes were consistent with relativity and proved that in them it was possible to travel back in time. He immediately realised that this implied that the past must still exist and that what he called "intuitive time" is therefore an illusion. In 1949 he published a formal proof that time (in our intuitive sense) cannot exist in any universe. This uncomfortable discovery was ignored for nearly half a century but was revived by Julian Barbour in "The End of Time" and is now widely discussed and accepted by many physicists.
    The Laws of Physics
    The fundamental laws of physics describing the forces are time-symmetric.
    What can we say about the time dimension?
    Time still exists but only as a chronological map in which events are located;
    Time is not in any way like the spatial dimensions because:
    It is anisotropic and contains an entropy gradient;
    If we exist in more than one location in any of the spatial dimensions then we will also always then be in different locations in the time dimension;
    Separations in 4 dimensions are extensions of Pythagoras's Theorem but have the form:
    separation = √[x2 + y2 + z2 - (ct)2], which means that time measurements are imaginary (ict) where i=√(-1), as Hawking suggests in "A Brief History of Time".
    Free will is also an illusion
    We live all our lives all the time but every instant feels like "now"
    Time travel is impossible because (a) there is no dimension in which travel is possible, (b) we occupy all the spacetime of our lives and cannot take back to an earlier time our memories of a later time.
    Stephen Warren · Marlow

    Is it reasonable to assume that space and time are both quantised at the Planck scale so that the magntude of the spatial dimensions increases at the rate of c (the speed of light) with respect to the time dimension (c=1 in Planck units)? 

    If so then the volume of space increases by (4/3 π) {(R + 1)3 – R3} Planck units of volume for each Planck unit of time, where R is the radius of the Universe at time t in Planck units.  The increase (~4πRto a close approximation as R is very, very large) allows for more alternative arrangements of the fixed amount of matter and might then be the source of the entropy gradient. The ratio of the increase in volume to the total volume would be ~1/(3R).

    I'm not sure of the maths but I've thought about it a lot!