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  • Mona Kamar asked a question in IR Analysis:
    How to get prepared Nano cellulose in a dry form?

    I want to do physical and chemical characterization for my prepared nanocellulose sample such as IR analysis, X-ray diffraction,degree of oxidation ... etc.So, do air or oven dry effect the sample properties. and if so what is the alternate way to dry it  without loosing its properties.

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

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

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

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

    Personally, I agree with Stanislas Dehaene's opinion.

    Arnold Trehub · University of Massachusetts Amherst

    The retinoid theory of conscious claims that the minimal condition of consciousness is like being centered in a surrounding space.

  • Jeff Habig asked a question in Feeding:
    Anyone know of contractors who perform 90-day feeding studies with rats?

    Hi - I'm interested in getting a list of contractors who provide rat feeding study services. Any help would be appreciated.

    Thanks - Jeff

  • Marković G. Đoko added an answer in Didactics:
    Why students do not think critically?

    I gave two mathematical questions/tasks to my students. 

    1. What is the solution set of x2 = 1?

    2. Given that triangle ABC is a right angled triangle. Angle ABC is right angle, and the measure of angle BCA is 60 degree. BD is perpendicular to AC. If CD is 1 unit long and BC is 3 unit long, what is the perimeter of triangle ABD?

    Students' responses to the first question was mostly {-1,1}. When I asked them is it the only correct answer, they said YES. They thought that the universal set of this equation is the set of real numbers R. Even when I said that there are many other possible universal set for this equation, such as {2} if the universe is the set of natural number, {-2} if it universe is the set of negative integers, and an empty set if its universe is the set of even integers, they did not take it into their considerations. They claimed that whenever there is no clear definition of the universal set, the universe of the equation should be the set of real numbers R. 

    To the second task students directly used pythagorean theorem to find the length of BD, and followed by finding the measure of side AB using the sine of angle BAC (which is 30 degree). Finally, they used these facts to find the length of AC, and finally AD. They did not pay any attention to the incorrectness of the conditions given in the problem. The incorrect proportion of BD:BC was ignored. 

    Based on the definition of critical thinking, skills and/or dispositions, I think they do not think critically. 

    Anybody can give an explanation of this phenomena? I need your points of view. If you can show me any theory and research results that can be used to explain this phenomena, it will be a great contribution to me.

    Thanks in advance.


    Abdur Rahman As'ari  

    Marković G. Đoko · University of Montenegro

    I think the main reason they have not been taught to think critically. I think that for such a situation, primarily blame the teacher.

  • Mary Giuffra added an answer in Flip Teaching:
    How many are still using didactic lecture as dominant way of instruction?

    Advocates of the flipped classroom approach argue that in a flipped classroom students can do more active learning. Many regard this as the main reason to flip. 

    I think this makes perfect sense in my case in China where didactic lecture is still the dominant way of instruction. However I'm not sure about the other parts of the world because my perception is that many education systems worldwide (esp. those in the "Western" nations) already have a lot of active learning components built into the curriculum. My questions are:

    1. Is my perception true?
    2. Is there any comprehensive statistics that can support or disprove my perception?
    3. If my perception is true, what is the point of flipping the classroom in those schools already doing active learning?

    Thank you. 

    Mary Giuffra · US Association for Body Psychotherapy

    One size never fits all.  Teachers and students often approach the teaching/learning process in various ways. Lecture is one of many different ways. Which method is most effective in getting specific learnings t o happen is a very individual dynamic.,.

  • Jacob Yu added an answer in Mineral Exploration:
    Can anyone recommend a modern up to date reference book on geochemistry applied to mineral exploration?

    I am an undergrad hoping to work in mineral exploration one day. Is this information I could learn by myself through a book or do companies keep the best practices "secret" and only teach it to employees? In either case, how do I start learning about this because undergrad courses are not too specific.

    Jacob Yu · Boston University

    Thank you both very much. I will try to form connections with my professors to hopefully be able to work with a company during my undergrad. Do you have any recommendations on how I can connect with mining professionals?

    "there are good reports from companies and geological surveys in Scandinavia and North America, which provide you with an up-to-date insight into the state-of-the-art in this geo-business."

    "You can also find a lot of practical data in journals, but also on web sites of Universities and Companies, especially from Australia and Canada"

    Could you give me a list of company websites I should look up and a link to an example of these reports so I know what to search the web for?

    I have read that a good first step in any mineral exploration program is to carefully study a similar previously discovered deposit and base your geochemical sampling off of that info. It sounds ideal, to have a "template" so you know what geochemistry you can expect if there is in fact a deposit. Are these kind of reports available on the web?

    I want to say that I really appreciate your guidance. Sometimes my undergrad professors are not very helpful with practical issues like this and I often feel overwhelmed at all the info out there.

  • Yifei Yuan asked a question in Lithium Ion Batteries:
    How much of a discharge sample from LIB electrode can be damaged is exposed to air for 1-2 minutes?

    I detach a Lithium ion battery coin cell after discharged the cathode. The cathode was then exposed to air for about 2 minutes. I want to know will the discharged electrode's structure changed due to exposure to air? The electrode material is alpha-MnO2

  • Dyoni Matias de Oliveira added an answer in Potato:
    How do I determine the reducing sugar percentage in potato?

    I am following Fehling's solution method to determine reducing sugar concentration (%). But during titration, I did not find any color changes. That's why I could not measure reducing sugar concentration(%). 

    For this purpose I need some suggestion of the process of reducing sugar determination and it will be very helpful for me.

    Dyoni Matias de Oliveira · Universidade Estadual de Maringá

    For total sugar use Dubois et al (1956).

  • Spiros Koutandos added an answer in Schrodinger:
    What is the nessecary condition for solutions of equation to form equipotential surfaces in space?

    For example for Laplacian in Schrodinger equation the solution is of the form psi=f(r)F(cos^2theta) so we may obtain the radius as a function of theta to be positive. What if it becomes negative? We all know of the lobes being created.

    Spiros Koutandos · ESPERINO

    We know for example that with complex functions in complex plane the solutions may cut the plane. It has to do with periodicity as well.

  • Muhammad Haris asked a question in Images:
    How to split image and then merge image using matlab?

    i see a research paper on image segmentation there i get idea to split image in different components then process but with in merging quality of image will be low down please mam provide me some instruction that how i can split image with minimal loss of quality using matlab

  • How can we use poems to foster students' higher order cognitive abilities?

    Competencies such as critical thinking, creativity, logical reasoning, inferencing, rhetorical devices, inductive reasoning, deductive reasoning, etc..

    Marković G. Đoko · University of Montenegro

    Mathematics is one of the few areas where during exercise tasks can use music, including songs. It has been shown that a very positive effect on perception, ie. solving problems.

  • Is Cognitive Behavioral Therapy effective for treatment of Internet Addiction Disorder?

    I read some papers suggesting that Cognitive Behavioral Therapy is effective for treatment of Internet Addiction Disorder. Does anybody here have experience with CBT for Internet Addiction? What do you think? Thanks

  • Is there a solid counter-argument against Dingle's old objection to Relativity Theory?
    Herbert Dingle's argument is as follows (1950):

    According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates,i.e. one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the 'moving' one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, 3 consistently with the theory, which clock works the more slowly? Unless the question is answerable, the theory unavoidably requires that A works more slowly than B and B more slowly than A - which it requires no super- intelligence to see is impossible. Now, clearly, a theory that requires an impossibility cannot be true, and scientific integrity requires, therefore, either that the question just posed shall be answered, or else that the theory shall be acknowledged to be false.
    Zhiliang Cao · Shanghai Jiao Tong University

    Dr. Olaussen,

    Please help me discover how this frame moves with respect to us!

    I think this is a very good question. This may be the main reason why we are debating. There is no experimental proof that leads us to such "preferred" inertia reference.

    The force and clock speed are related:

    a= c 2 *dT/ds

    In my paper, it is dD/ds, which is same as dT/ds.

    A small clock rate change implies big force. Physics experiment cannot measure the true distance of an inertia reference in space. What we got are distances and time of the matters that have static relative positions among each other. Therefore, there is no "moving" inertia reference other than force bonded matter reference available for us. The matter reference will "prevent" us from finding out the "preferred" inertia reference as the clocks are "synchronized" by forces.

    The impact of the gravity on the clock (as we may know via our GPS experience) adds additional parameters. What we usually see is clock drifting in lunar or day/night cycles due to the gravity forces. See the attached paper for further details.

  • Can anyone advise where I can find some articles about "Life Satisfaction" and "Onilne purchase intention"?

    I will start a new research about internationalization. I would like to find theory about these constructs. Anyone can help me?

  • What are the best methods of supravital staining?

    I am doing an experiment where at some point I need to access whether some cells are alive or not. I need a supravital staining method or something else.

    Juliana H C Smetana · Centro Nacional de Pesquisa em Energia e Materiais

    Try the MitoTracker  fluorescent stain for mitochondria from Molecular Probes. Uptake is dependent on the mitochondrial membrane potential and it is widely used as viability indicator. It would be even better to combine positive and negative evidence in the same assay.

  • Can we generalize Laplace-Beltrami operator to fractional Brownian surface?

    One of basic assumption used in Laplace-Beltrami operator is that the surface is smooth. But what if it is not smooth? Can we generalize Laplace-Beltrami operator to fractional Brownian surface? (In cosmology, various perturbation of Cosmic MIcrowave Background spectrum may be associated with non-smooth surface).

    What do you think? See my paper below. Your comments are welcome.

  • Hs Guruprasad added an answer in Compiler Design:
    How does the left recursion affects the context free grammar?

    I'm reading about context free grammar and i recognized how to eliminate the left recursion but i did not find out what is the problem with left recursion?? can any one explain 

    Thanks in advance

    Hs Guruprasad · BMS College of Engineering

    The left recursion brings in infinite looping during the implementation. Therefore, it has to be eliminated.

  • Raimy Haidar added an answer in Abaqus:
    How to solve these issues (Frequency Extraction & applying load problem ) - ABAQUS?

    Dear friends,

    Currently im having two issues and uncertainties regarding on Abaqus analysis process:

    i. Does Abaqus CAE has the capability to perform linear perturbation of Frequency and Modal analysis with the action of g= 9.81m/s^2 towards the whole model? 

    ii. How to apply load on a specific location, where the point does not appear in Abaqus? (as shown in attached figure) , Is there any solution to create a node on that location ? 

    Helps needed, best regards.

    Raimy Haidar · Universiti Tun Hussein Onn Malaysia

    Thank you C.Martin for your reply.

    The *STEP you mentioned above is refer to STATIC,GENERAL ? 

    Best regards.

  • Getachew Agegnehu added an answer in Symbiosis:
    Is that possible to derive the amount of biologically fixed N by legumes if the nodule dry weigt per plant is known?

    Root nodule symbiosis helps nitrogen‐fixing bacteria convert atmospheric N into a form that is directly available for plant growth. But I couldn’t find a research finding which indicates whether it is possible to directly determine the N fixed based on modulation number and weight.

    Getachew Agegnehu · James Cook University

    Thanks a lot Michael for your elaborated comments. I need the mass of N fixed until the time when the plant samples were taken for nodule biomass determination, which is normal after 50% flowering.

  • Is the remark of Richard Feynman (I think I can safely say that nobody understands quantum mechanics) still valid or acceptable?

    Regarding our current understanding of quantum mechanics, especially the interpretation of the theory of measurements in terms of parallel universes.

    Theoretical physics, quantum mechanics, Fundamental physics 

    George Stoica · Mathematics and Statistics

    Kåre - I am thinking about the philosophical speculation about the role of the observer, and the speculative quantum gravity theories. Plus, the statistical nature of our knowledge of reality can be considered as a speculation as well, but one that can be measured.

  • Has there been any research on comparing science teachers' professional development in western and non-western context ?

    Any article or report discussing the implementations or experiences of such programs 

  • Would particle and anti-particle move away from each other with accelerated motion?

    When a fundamental particle anti-particle pair is created in perfect vaccum in the absence of any other matter, would the two particles move away from each other with accelerated motion or with decelerated motion? Are there any experimental data on this subject? Particle pair can be anything. Two leptons or two bosons or two top quarks.

    Biswajoy Brahmachari · Vidyasagar Evening College

    No, the question means virtual particle-antiparticle pairs.

  • Contributions for Thematic Issue in 'Natural Products in Oral Health' for "The Open Dentistry Journal" (PubMed Indexed)?

    I am pleased to tell you that I have been invited to publish a special issue for the The Open Dentistry Journal on the theme ‘Natural Products in Oral Health’. The appropriate articles would include on natural molecules / traditional medicine effect on oral health or on mitigation of oral disease. I would request for your kind contributions in form of original research or reviews. The author guidelines is available at http://www.bentham-open.com/TODEN…/instructions-for-authors/ . The journal has assured of waiving off the usual author fees. The journal is open access, pub med indexed. Assistance preparation of manuscript or for English correction/translation if required can be arranged. The manuscript will pass through the blinded peer review process. Pass this information if found useful to other researchers on natural products related to oral health.
    Kindly acknowledge if of interest and if so send the manuscript to me in my email address following strictly the author guidelines before 31st May2015. If need more time please mail. Any clarification, just a mail away. shajujacob@yahoo.com

  • John Kasab added an answer in Gears:
    When I am running a vehicle in a particular route, how to calculate Engine RPM?

    I want to map a particular route duty cycle for a vehicle. During that time, how to calculate the engine RPM when the vehicle runs in that particular route. I already know the vehicle specification like its Engine max power, Engine max torque, Tyre rolling radius, individual gear ratios, Rear axle ratio. My question is:-  Driver may use any gear at anytime depending upon the route condition. When I am running a vehicle in a particular route, how to calculate Engine RPM?? 

    John Kasab · Ricardo, Inc., United States, Van Buren Twp., MI

    Arul, it sounds like your engine does not have a CAN bus? Because you should be able to measure engine speed using a scan tool.

    Otherwise, you have to back out the engine speed from the vehicle speed and the various ratios from tire to engine flywheel. You will need to know the rolling radius of the tires to get the rotational speed of the wheels, and you will need to know the gear. I assume you do not have a torque converter on the transmission input?

  • Abdul Nasir asked a question in Nails:
    Which is name of the syndrome have deafness with thick nail of one hand particularly thumb nail?

    i have family of syndromic deafness with thick nail of one hand and particularity the thumb nail. plz any one suggest me the syndrome name

  • Ning Li asked a question in Polyoxometalates:
    How to calculate or get references on the g-factor of transition metal ions?

    In calculating the magnetic susceptibility of polyoxometalate clusters, g-factor is needed in the formula of x=(g^2)S(S+1)/8. I am wondering whether there is a way to calculate the g-factor for different transition metal ions or a reference list showing the values. 

    On separate, how does the g-factor depend on the status of specific transition metal ions? e.g. oxidation state, coordination number, bonding atoms, etc. 

    Thanks in advance.

  • Hamid Esmaeily asked a question in Maine:
    What is the main use of rotary phase converter ?

    What is the main use of rotary phase converter ?

  • Hamid Esmaeily asked a question in Induction Motor:
    How do you size the capacitor rating required for an induction motor?

    How do you size the capacitor rating required for an induction motor?