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  • Chayuti Mekurai asked a question in Balance:
    How can I measure static balance with Nintendo Wii Fit balance board ?

    I want measure static balance with stand on Nintendo Wii Fit balance board and evalate Center of  File ressure (COP)

  • Emad F. AL-Shareefi asked a question in Distribution:
    What Laplace distribution applications?

    what Laplace distribution application

  • Francisco Liñán added an answer in Entrepreneurial Skills:
    Does the theory of planned behaviour help in predicting entrepreneurial intention among students?

    Is the theory of planed behaviour relevant in entrepreneurial study

    do intentions predict behaviour

    can entrepreneurship behaviour be predicted

    Francisco Liñán · Universidad de Sevilla

    One of the key issues now is understanding when and how intentions translate into behaviour.. As our literature review shows, longitudinal research is still scarce.

  • Mushtaq Ahmad added an answer in Seaweed:
    Is Enteromorpha intestinalis, a green seaweed species, edible?

    I try to make some food products from this species. Please provide me some articles on this question if answer is "yes".

    Mushtaq Ahmad · Pakistan Atomic Energy Commission

     Some details are in:


  • Arno Gorgels added an answer in Event Horizon:
    What do you think about the S. Hawking`s idea of the solution of information paradox?

    "I propose that the information is stored not in the interior of the black hole as one might expect but on its boundary, the event horizon,"

    At Monday's public lecture, he explained this jumbled return of information was like burning an encyclopedia: You wouldn't technically lose any information if you kept all of the ashes in one place, but you'd have a hard time looking up the capital of Minnesota.

    The translations that occur form a sort of hologram of the original particles, Hawking said -- a hologram in the sense that 3-D information is recorded on a 2-D surface. When radiation leaves the black hole, it carries some of that information preserved on the event horizon with it.

    Arno Gorgels · Principia Naturae

    In 1929 the expansion of the universe including big bang has been decided

  • Josiah Liu added an answer in DMSO:
    Why was there size difference measured by TEM and DLS?

    Can anyone tell me why there was a big size difference bettween TEM and DLS? My particilce formed by metal organic homopolymer(DP=20)  in DMSO measured by DLS was 500 nm but TEM was less than 200 nm. Could anyone tell me why?

    Josiah Liu · University of Waterloo

    Thanks all for valuable suggestions

  • Jakub Jakowiecki asked a question in NAMD:
    Where can I find some turotial/documentation on the "measure" command in NAMD ?

    I know how to use "measure" command in TCL/VMD but it appears it does not work the same way when used in NAMD configuration file. For example if I wanted to refer to a certain atom current coordinates in the input file, how should I do that?

  • Hassan Azari added an answer in Neural Stem Cells:
    How to remove or kill the astrocytes in neural stem cell differentiated culture?

    Hi All,

    I was cultured neuron stem cells and want to get many neurons from it, however it usually gives a lot of astrocytes and a few neurons, I want a way to remove, or kill these astrocytes. I see some beads which can bind GFAP so remove astrocytes, but as neuron stem cell also express GFAP, I don't want to remove it, so can't use the beads, any good ideas?

    Hassan Azari · Shiraz University of Medical Sciences

    Hello Monica,

    As long as it is a high quality serum, it makes no difference to use FCS or FBS.

    Wish you all the best with your experiments.


  • Joseph N Stember asked a question in DICOM:
    Are there any publicly available dicom ultrasound images of renal stones?

    or JPG made directly from dicom images

  • Juan Antonio Arizaga Silva added an answer in Simulink:
    Can the GUI (Graphic User Interface) in matlab be used as an input in Simulink block diagrams?

    I'm working in matlab/simulink.  I have made Simulink model for 1 equation and giving constant (block) as a input. At the same time, I have made one GUI where u will get a pop up asking the input to be entered. now i want to use this value from GUI as a input to simulink equation. How to do that?

    Juan Antonio Arizaga Silva · Universidad Politécnica de Puebla

    Yes, you can call the GUI by passing it as a parameter in the callback section in Simulink MOdel properties.

  • Srimeenakshi Sankaranarayanan asked a question in Down Stream Processing:
    What are the recent development in down stream processing?

    what are the recent development in down stream processing?

  • Mae Riley asked a question in Astrocytes:
    Has anyone observed a recovery of pHi in cultured rat astrocytes during perfusion with Na-free HEPES?

    1. Rat primary cortical astrocytes incubated in BCECF 30mins.

    2. 20mM NH4-prepulse 5mins.

    3. Na-free HEPES 5 mins.

  • Csaba Istvan Timar added an answer in Erythrocyte Aging:
    Does autologous IgG attenuate complement activity of normal plasma?

    Paradoxically, high doses of Immunoglobulin G from pooled human sera have been used intravenously for treatment of some chronic inflammatory diseases (Newburger JW et al. N Engl J Med 3 15:341, 1986; Ronda N et al. Vox Sang 64:65, 1993), presumably based on its complement attenuating properties (Lutz HU et al. Blood 88:184, 1996; Lutz HU et al. Blood 103:465, 2004). Band 3 modifications likely to occur during RBC ageing enhance membrane affinity for normally circulating antiband 3 antibodies and bring about limited complement activation (Arese P et al. Cell Physiol Biochem 16:133, 2005). I wonder if autologous IgG is at a high enough concentration in normal serum that it may attenuate complement activity in spite of potential amplification of the immune senescence response during erythrocyte ageing. I would greatly appreciate comments on the subject.

    Csaba Istvan Timar · Semmelweis University

    Hi, Dr. Romero,

    I don't have exact experimental proof, it is just an odd - and yet unfollowed - side-result, but when You try to determinate the blood group of a sample in the presence of the blood plasma, and You use a huge volume of anti-AB0 antibodies, there is no (or not so fast) haemolysis, meanvhile there is a detecable and relatively fast haemolysis in the presence of samall amount of anti-AB0 Ig-s. (Of course, only when the anti-AB0 reacts with the AB0 antigenes.)

    Regards: Csaba

  • Tomasz Waclawczyk added an answer in Two Phase Flow:
    What is the point of performing transient calculations?

    I'v been doing an investigation between seady and transient solvers in Fluent. I modelled a two phase flow in a horizontal pipe for both steady and transient, and the results are very similar. So is that means the case is completely steady?

  • Robert Hedin added an answer in Carbonates:
    How can I quantify the presence of carbonate and bicarbonate in water?

    Can anyone help me how to calculate the amount of carbonate and bicarbonate ions (mg/l) present in water ? 

    Robert Hedin · Hedin Environmental

    I did not understand that this is water obtained from a hydrocarbon reservoir.  I am in surface water mode.  I cannot comment on the alkalinity of waters produced by hydrocarbon reservoirs.  Sorry for the confusion. 

  • Saeed Darya Zadeh added an answer in Residual Stress:
    How can various components of residual stress be measured by a experimental method?

    I’m planning to measure residual stress in z and r (radial) direction of a machined specimen..

    Saeed Darya Zadeh · Kharkiv Polytechnical Institute

    There are articles about residual stresses in Russian references.

    You can search for phrase ''Экспериментальные методы для oстаточных напряжений'' and You can see their references in English language.

  • Dejenie A. Lakew added an answer in Philosophy of Physics:
    A significant tension exists among the philosophies of individual sciences. Is there a need for a general philosophy of science?

    Philosophy of science is the branch of philosophy that studies the fundamentals, the assumptions and implications of science, in relation to logic and the natural sciences, such as physics or biology, both with respect to the social sciences, such as sociology, psychology or economics.

    Philosophy of science is linked in general to the philosophy of knowledge and epistemology. It seeks to explain the nature of the concepts and scientific statements, the ways in which they are produced; how science explains nature, how is predicted, and as it uses for its purposes; the means for determining the validity of the information; the formulation and use of the scientific method; types of reasoning that are used to reach conclusions; the implications of scientific methods, with models of the scientific environment and human society surrounding.In the most common sense, philosophy of science is the study of how is the scientific knowledge. It has large overlap with epistemology and several themes in common with the problem of demarcation. When we need to identify what exists, whatever the object of which we speak, ontology and epistemology will also be involved. In the philosophy of science has a certain importance also logic both for its connection with the deductive methods, and for its close ties with the philosophy of mathematics.

    Philosophy of science can also be in the plural, as internal reflection to a scientific community on the philosophical aspects relating to a common discipline of competence, so we get the philosophy of physics, mathematics and other philosophical sectors.

    It is part of the philosophy of science also the ethics of science, which deals with its moral aspects. "Science as an institution implies a tacit social contract among scientists so that each is dependent on the reliability of the other [...] the whole cognitive system of science is rooted in the moral integrity of the whole of the individual scientists.

    In the historical development of the philosophy of science, particularly important reveals the twentieth century. At its beginning it were basic the studies of historians and philosophers Ernst Mach and Pierre Duhem that inspired the philosophers gathered in the Vienna Circle, a group of scholars who met regularly in Vienna from 1922 until 1936 to discuss issues of philosophy of science. Among the members of this group most active were Rudolf Carnap and Moritz Schlick. To be mentioned in the debate on philosophy of science, especially in relation to Popper, was Paul Feyerabend. Karl Popper, an occasional visitor to the Vienna Circle, contested the issue of ‘experimental’, to which opposed the criterion of falsifiability.

    Incidentally, more or less in the same years developed, thanks to the initiative of Hans Reichenbach, the Berlin Circle, who took charge of the same themes, but with an emphasis on causality, statistics and the predictive power of science.

    Kuhn criticized partially Popper’s falsificationism on the point concerning the casting aside of the theory in the case of empirical refutation of one of its elements, arguing that it should have been set aside only that single element and not the theory as a whole.

    Also Lakatos, while welcoming the philosophical setting of Popper, claimed that were never the single refutations of empirical facts to determine the abandonment of a theory, because the questioning of scientific truth would cover only a marginal part of it, not its core, that although weakened in its overall certainty, would continue to be accepted as true. For a general theory to be abandoned, according to Lakatos, it should rather have a new comprehensive program of scientific research being able to give an account of the events: it is not the falsification in itself to cause the progress of the science, but the spirit of research and human ingenuity-

    After the dissolution of the Vienna Circle in 1936, studies in this discipline continued in various European and American universities. Among the developments of the last decades of the twentieth century are remembered the important contributions of the American philosopher Thomas Kuhn and Hungarian Imre Lakatos related to research programs and to the progressive development and evolution of scientific theories.

    Professor Mauro Dorato speaks of a "significant tension that existed among the objectives of the different philosophies (" local ") of the individual sciences, more and more " technical "and specialist, and the essential need of a general philosophy of science , seen in a synergistic context with other branches of philosophy – from ontology to epistemology, from metaphysics to ethics. "

    He concludes his article with these words: "The philosopher of science, unlike the scholar of the foundations of the individual sciences, does not intended to raise the knowledge within a particular science. He / she has only the goal, not less important, to understand it better, comparing it with the image of the world that was deposited both in our pre-theoretical experience and in the implicit theories in the use of natural languages. It follows that the acquisition of a technical-scientific knowledge, if it comes from the philosopher of science inclined to a "synthesis" work, has the essential object, already mentioned, to probe the consequences of certain scientific theories, considered as "given" or acquired, on issues of "border line", which, for example, are those of the relationship between time and space of the physical world (space / time) and the time and space of our conscious experience, or among the numerous and complex neural connections and phenomenology of our mental states”.

    Dejenie A. Lakew · John Tyler Community College

    Philosophy of science, I assume is a necessary blue print on which the human society creates,  advances and utilizes science to its service. It is that philosophy that forces the entanglement of different parts of science to function together for better results. The problem I see at the moment is that philosophers of science in most part are devoted and passionate thinkers who observe science not by being inside but  from outside and make analysis about science. It is easier to comment on an art performance than to be one of the actors in the play and do flawless performance. 

  • Gulzar Ahmad Nayik added an answer in Food Biochemistry:
    Is there a correlation between antioxidant activity and mineral content?

    Is there any correlation between antioxidant activity and Mineral content in food material?

    Gulzar Ahmad Nayik · Sant Longowal Institute of Engineering and Technology

    U. D. Chavan · Thank u sir

  • Srimeenakshi Sankaranarayanan asked a question in Calcium:
    What is the basic principle of calcium frequency encoding signalling system that is used for calcium quantification in cells?

    What is the basic principle of calcium frequency encoding signalling system that is used for calcium quantification in cells?

  • Henry Tregillus added an answer in Foundations of Quantum Mechanics:
    Is the collapse of wave function after measurement a reality or a science fiction?

    For entangled particles the measurements of a physical property related to entanglement leads to collapsing of wave function to a certain state instead of two states previously. This against causality and locality. The non locality can be admitted but causality breaking is against most of the physics laws. why we don't assume each particle has its own state from the moment of creation till measurement. why we don't adopt realistic quantum mechanics if there are new theories that can succeed in interpreting the quantum phenomena  and respect locality and causality. What do you think?

    Henry Tregillus · Fort Lewis College


    We may not understand what exactly the wavefunction is, but did we understand what apples truly were when Newtonian mechanics came to be? Mostly the suggestion of a reality is held back by Descartes' most popular thinking; to sum it up in a sentence, are we a brain in a vat?

    This probably seems like a silly attack on the Copenhagen interpretation, but I think it's the best perspective to hold when it comes to quantum mechanics. Observables are states which act as individual quanta; when particle physics comes in, it becomes clear that each quanta has not only two "positions" (states) but it has a number of states with respect to charge, flavor, color, even mass as we've recently discovered.

    To go further, the Dirac sea is a great starting point to visualize how quanta wavefunctions can be excited from the vacuum, with pair production being not a sudden manifestation, but rather a breaking of the symmetry of empty space.

    You guys are largely debating nonlocality though, and an important thing to remember is that nonlocality onto presents itself upon classical intersection. That is to say, we can only be sure of the correlation when we actually compare the results by causing the superpositioned wavefunction future (here is where the many-worlds interpretation comes in) to overlap. There is no violation of Einstein locality; the breakdown of two regions of spacetime is always symmetric when you see the two worlds come together. The wavefunction "collapses" not instantaneously but over the course of the measurement process. This is so often forgotten that it gives rise to all of this nonlocality talk. We don't SEE the wavefunction collapse; we KNOW it has collapsed due to the correlation of entangled quanta.

    Anyways, bit of a rant, but yeah. I've come to this conclusion about quantum mechanics after exploring quantum information theory; it is an abstraction of the basic "physical" quantum mechanics, but it does follow the rules of the wavefunction, whatever they may be.

  • Mushtaq Ahmad added an answer in Molecular Bacteriology:
    How can I measure acetate in bacterial culture?

    I use acetate as sole carbon source in bacterial culture, I'd like to get a colorimetric method using spectrophotometer to measure it, can I get help for that?

    Mushtaq Ahmad · Pakistan Atomic Energy Commission

    Can you try acetate colorimetric assay kit?


  • Abbas Majidi added an answer in Polarization:
    Can someone suggest a good software/tool to model the polarization and polarization dependent effects of light?

    I am unable to model polarization of light and anisotropic materials in MATLAB. Is there a better alternative?

    Abbas Majidi · University of Tehran

    I suggest you to use Mathimatica because it can solve problems analytically and also matrix forms in this software are very similar to writing analytic form on paper.

  • Aamir Habib added an answer in Internet of Things:
    Could anyone recommend papers that explore the application of the Internet of Things from a educational/learning prespective?

    I can find little research outlining the value of IoT in higher education. Has anyone else had more luck?

    Aamir Habib · Institute of Space Technology

    interesting application for Iot indeed. Well yes you would not find any papers on that. its something new and not people are going for it.Well i think its a very good things to use Iot tech for learning and teaching.

  • Geetak Gupta added an answer in Semiconductor:
    Why does a semiconductor when heavily doped become metallic (temperature independent) at very low temperature?

    Taken a doped semiconductor at high impurity concentration such that the impurity states are extended in nature, as we lower the temperature, resistivity show weak temperature dependence i.e. very small increase of resistivity with decrease in temperature. If the temperature is lowered further the resistivity becomes independent of temperature, why is it so? Normally, if one reduce kT less number of carriers will move and hence resistivity should increase !

    Geetak Gupta · University of California, Santa Barbara

    If the doping is low and the donor band is separate from the conduction band, as temperature is lowered, Fermi level starts settling somewhere between the donor and conduction band. Due to this, the number of free carriers in the conduction band keeps going down. This is called freezing out of dopants. Once the doping is so high that the donor band merges with the conduction band, the free carriers cannot be frozen out because now there will always be states around the fermi level.

  • Carlos G. Oliver asked a question in Gromacs:
    How do I generate distance matrices for specific frames in trajectory with GROMACS g_mdmat?

    I would like to generate individual and mean distances for a trajectory using g_mdmat from GROMACS. That is, I have a list of time points in the simulation (which are not interspersed at a regular interval) that I wish to use to calculate distance matrices with. I can't find any option in the g_mdmat options list that can allow me to do this. Is there any way I can accomplish this?

    Second, I wish to have access to the numerical values of the matrix but the .xpm output format is not easily parseable, is there a way to have access to the distance values produced by g_mdmat?

    Thank you!

  • Puspendu Barik added an answer in Nanoparticle Research:
    What are the roles of the reagents used in a typical synthesis of cadmium selenide quantum dot nanoparticles?

    The reagents/chemicals are as follows: CdO, octadecene, oleic Acid,  selenium
    trioctylphosphine, etc.

    Puspendu Barik · Universidad Nacional Autónoma de México

    Methods for preparing colloidal CdSe quantum dots (QDs) can be divided into two categories depending on the nature of the solvent. Wet chemistry uses low temperature polar solvents such as water or methanol. Organometallic synthesis uses high temperature, non-polar solvents such as trioctylphosphine oxide (TOPO). Within each category, there are numerous variations in the exact precursors, solvents, and special additives. The wet chemistry routes generally produce lower quality nanocrystals, with smaller and wider photoluminescence emission peaks and organometallic synthesis route can produce better quality nanocrystals. Moreover, most of the CdSe QDs synthesis method, CdO is dissolved in oleic acid (to form a cadmium oleate complex), while Se is dissolved in TOP. Higher concentrations of oleic acid may inhibit nucleation by capping nuclei more effectively and making it harder for them to grow.

    CdO - This is for Cd ions source.

    Oleic Acid (OA)- A natural surfactant, was chosen as the surface-binding ligand for stabilizing the nanocrystals and the cationic precursors. The Cd-ligand complex must be less stable than CdSe in order for the synthesis reaction to have a driving force to proceed. Ligands keep the particles isolated, thus preventing nuclei agglomeration and facilitating homogeneous growth. Nanocrystal size variations are reduced when ligands control the growth rate of particles. Ligands passivate the surface and bind to the surface during organometallic synthesis naturally provide surface passivation, which protects the surface from oxidation and minimizes the electronic trapping properties of surface defects, both of which help to maintain high quantum yield.

    Octadecene (ODE) - It is used as a non-coordinating, high-boiling solvent which is a liquid at room temperature and boils at about 320 °C.  As the concentration of oleic acid in ODE decreased, the growth rate of the nanocrystals slowed down systematically, and the size distribution of the resulting nanocrystals became significantly narrower at the focus of the size distribution. With ODE as noncoordinating solvent and an appropriate amount of oleic acid as ligand, the size of CdSe nanocrystals can range from approximately 1.5 to 20 nm in a controllable fashion.

    Trioctylphosphine (TOP) - Act as the coordinating solvent and Se powder's solvent also to provide better size control and surface passivation. Quantum dot crystal structure can be controlled by the choice of the main reaction solvent and temperature. CdSe nanocrystals grown in TOPO or fatty acids generally have the wurtzite structure, while zinc blende structures are often observed in CdSe quantum dots grown in amines at the same reaction temperatures. 

  • Chompoo Berry asked a question in LB Agar:
    Do you have any tips for using antibiotic in the production of LB agar ?

    Any tips for using antibiotic in the production of LB agar which is just taken out of an autoclave that would not denature the antibiotic with heat and prevent agar from transforming into jelly due to low temperature?

    I have previously used it when it was cold that LB agar's surface turned rough or it get too cold that could not pour. When I used the microwave it got too hot that denatured the antibiotic and LB agar got contaminated.

    Can we do it separately by putting LB and agar in different containers then autoclave before mixing them?

  • Vikant Bhateja added an answer in Wavelet:
    Where to begin for Wavelet Decomposition technique for Drives application??

    Hi there,

    I want to work with wavelet decomposition technique for online detection in both Matlab simulation and DSP both..

    Please suggest where to begin with..

    Vikant Bhateja · Shri Ramswaroop Memorial Group of Professional Colleges

    You may refer the tutorial and attached papers.

  • Waqas Anwar added an answer in Plant Modeling:
    Do you know any linearized plant model of wind turbine which is 'initialized'?

    There are plenty plant models of wind turbine in the literature but I am looking for a state space model which is 'initialized' having four matrices (i.e. A, B, C, D) consisting of only constants (no variable in matrices). Preferably, a model consisting of all matrices of 2x2 size.

    I need it to design a Model Predictive Control (MPC) based Blade Pitch Angle Controller of Horizontal-Axis, Variable-Speed Wind Turbine.

    Waqas Anwar · COMSATS Institute of Information Technology

    Jacopo Serafini: Thank you for the quick response!! I need to include both (rotational dynamics and pitch dynamics). It's important that the state-space parameter values are provided and all four matrices are of 2x2 size.