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  • Newton Pimentel de Ulhôa Barbosa added an answer in Reptiles:
    What are the indicators to measure stress level in reptile with hemoparasite but no clinical signs?

    Pathophysiology of hemoparasite in reptiles.

    Newton Pimentel de Ulhôa Barbosa · Bioengineering Centre of Invasive Species - CBEIH

    It's just an assumption: maybe the fluctuating asymmetry?

  • Manuel Morales added an answer in Electrostatics:
    Could the fundamental dimension of Electric Charge be Mass only?

        After solving dimensions of electrical equations, I found out that the fundamental dimension of Electric charge is mass only. This also leads to the derivation of dimensions of other Electrical units like Electric Current, Magnetic flux density etc in terms of Mass, Length and Time only. These are not cgs units.
         This discovery can help unify the force of gravitation that uses mass and the electrostatic force(Force between charges).This will help contribute to the theory of everything, also in better understanding of the electrical units and equations. e.g Work done=Charge times Voltage. Substituting the right handside with their dimensions of Charge=Mass and Voltage=L^2T^-2 proves that the equation is dimensionally consistent. Also other theories can be uncovered and better understood with this finding.
         I wish to be challenged if possible and I will show the steps of the derivation.

    Manuel Morales · TemptDestiny.com - Prephysics Research

    "Because the first sentence, that does make sense, is irrelevant to the subject at hand, which assumes a background knowledge of physics, taught at all universities"

    That is exactly my point. The logic used in science to perceive reality is illogical. It places cause second to effect which is a violation of temporal precedence. At one time it was taught that the world was flat until someone came along and thought for himself.

    If physical scale and locality are fundamental, then how can physics be fundamental if it cannot answer the following question:

    How much does a direct or indirect selection weigh, what are their scales, and where was the mutually exclusive selection variable you used to read these words located when you used it?

    "...and the second statement, that's been repeated a large number of times, is a meaningless statement and simply spams any discussion thread."

    The question is meant to illustrate how illogical our current logic is. What is meaningless is to have a discussion that ignores how we are able to have this discussion in the first place. To spam past knowledge when new knowledge has been obtained that supersedes previous knowledge is like having a discussion that the world is flat when empirical evidence shows that it is not. Such a discussion is not science.

  • Gourisankar Roymahapatra added an answer in Hexanes:
    Has anyone checked the effect of hexane cytotoxicity on cell lines, I mean as a control and what was the result?

    cancer apoptosis by hexane extraction method for medicinal plant

    Gourisankar Roymahapatra · Global Institute of Science and Technology, Haldia, India

    The cytotoxicity of hexane can be tested empirically using MTT assay.

    But, it is not seems to be much accurate as it evaporates readily.

    It is better to remove the solvent (hexane), you will obtain  solid compounds first, and then dissolve in preferred solvents and then go for cytotoxicity study.

  • Newton Pimentel de Ulhôa Barbosa added an answer in Ecology:
    I have a list of endemic species. How can I analyse them statistically?
    Endemic species
    Newton Pimentel de Ulhôa Barbosa · Bioengineering Centre of Invasive Species - CBEIH

    You can do predictive models, and discuss the environmental variables envolved with the endemicity patters...

  • Raul Simon added an answer in Steam:
    Is steam turbulent in small scales?

    First of all as I have read most clouds are of turbulent nature and the condensation and evaporation of water is affected by turbulence. We can tell by their shape. If now vapor in small scales is turbulent it would explain its big value of entropy for a start.

    Raul Simon · L A M B

       What makes turbulence so complicated is that eddies are present in all scales (short of the quantum range). So, since  steam is  turbulent at large scales, it is also turbulent at "small" scales.

  • Ulrich Mutze added an answer in Quantum:
    Why do we use equal time commutation relation in quantum field theory, what is the commutation relation if time is not equal?

    Scalar field quantization

    Ulrich Mutze

    Clifford, your wording confuses me, a non-native speaker of American. Do your words say that you  prefer Schweber (over Weinberg) ?

  • Daniel Wright added an answer in Post-Hoc Analysis:
    Is there a post-hoc test for Kruskal-Wallis?

    specifically, I'm looking for one in R.

    Daniel Wright · ACT, Inc.

    As alternatives to the solutions put forward above ...

    The p.adjust function (with its different methods, Holm's is the default) uses the p values from your pairwise comparisons.  This is built into functions for ANOVA/t-test, so could do on ranks. For example,

    g <- sample(1:5,1000,replace=TRUE)

    x <- rnorm(1000,g/10)


    Of course doing it this way depends on why you chose the Kruskal-Wallis test.

  • Michael Schacht asked a question in Embodied Cognition:
    Who knows commentaries, opinions on Gregory Hickoks "The myth of mirror neurons"?

    As a psychotherapist I am interested in research on embodied, situated, grounded cognition. Hickoks critique of these approaches seems to be sound. Since I am not an expert in the field of neuropsychology I would like to know if there are arguments to question his position. How do the protagonists of embodied cognition object to his arguments?

    Thanks for your ideas, Michael

  • Ali Raza Shafqat asked a question in Nanorods:
    Which solvent is best for dispersing Zinc Oxide Nanorods in epoxy?

    Please suggest best solvent and surfactant for dispersion of ZnO in epoxy

    Recently I have used DMF but on curing the composite bubbles were entrapped in it.

  • Zian Fanti added an answer in 3D Visualization:
    Any advice on brain blood vessel segmentation in CT image?

    I have a project in my university. That is how to segment brain blood vessel in CT image. I can segment it in 2D image by using FCM. But it more difficult than segment brain tumor in MR image :D

    And i don't know how to shape it into 3D visualization. Could you refer me any method which can be. 


    Zian Fanti

    You can have a look to this method. 



  • Nizar Matar added an answer in Inclusive Growth:
    Can India make an act on land acquisition which balances the diverse interests as well as ensures inclusive growth?

    Can India make an act on land acquisition which balances the diverse interests as well as ensures the national cause of an inclusive growth?

    Nizar Matar · An-Najah National University

    This is my opinion which may sound strange. A land has to be utilized either for agriculture or building house(s) or establishing projects. When someone or some family owns a vast land, say more than 200 hectares, the government ought to give the owner, say 3 years, to make use of the land for self-benefit & for the advantage of the country. If it is not exploited, then there ought to be  land acquistion  & piece by piece, the land is to be divided & granted to those who will use it. The closest relatives of the person or the family (previous owners) will have priority in this acquisition process in order to diffuse any consequent complaints or protests or problems. If the land stays obsolete, then it is re-taken & given to someone else (possibly the original owner). In any case, the land is for the active & the lazy is put aside.

  • Gourisankar Roymahapatra added an answer in Pseudomonas aeruginosa:
    How can I solve and evaluate Pseudomonas aeruginosae biofilm in microtiter plate assay?

    In wells there is very distinct and visible the  liquid-air interface
    standing cultures line. 

    How big volume of  33% Acetic acid should be? Do i need to cover the liquid-air interface  line and solve it? Or add small volume of 33% Acetic acid to avoid this line?

    Gourisankar Roymahapatra · Global Institute of Science and Technology, Haldia, India

    You can go through the following articles

    1) Journal of Microbiological Methods
    Volume 105, October 2014, Pages 134–140

    2) Nature Protocols 5, 1460–1469 , doi:10.1038/nprot.2010.110

    3) J Vis Exp. 2011; (47): 2437, doi: 10.3791/2437

    4) Jundishapur J Microbiol. 2014 February; 7(2): e14358., DOI: 10.5812/jjm.14358

  • Frank Fortunat added an answer in Startups:
    Is there any paper suggestions for business failure prediction for startups and mature companies?

    I am looking for the most relevant papers in that direction. 

    I would be happy about recommendations.

    Frank Fortunat · Technische Universität München

    Thank you all for your input. You really helped me a lot!

  • Manfred Sager added an answer in Soil Dynamics:
    Can anyone suggest a suitable method to study the speciation of heavy metals in soils?

    Is the Tessier method the standard one, or any other modifications to the Tessier method?

    Manfred Sager · Österreichische Agentur für Gesundheit und Ernährungssicherheit

    In a series of aerobic arable soils, the  solubilities of P were much more different in various extracts, then for sulfate (unpublished)

    0,01M CaCl2 1:10  P) 2,7 +/- 2,3     S) 8,8 +/- 8,1 mg/kg

    0,5M NaHCO3 1:20    57,8 +/- 30,3      30,6 +/- 14,3

    0,2M Oxalate pH 3    529 +/- 225         56 +/- 36

  • Muhammad Farooq Ahmed added an answer in Penetration Testing:
    What is the relationship between SPT- N value and DCPT-N value?

    I need to know about the numerical relation between SPT (Standad proctor test) N (number of blows) value and DCPT (Dynamic Cone Penetration Test)  N (number of blows). If You specify the relation as per IS code its very useful for me.

    Muhammad Farooq Ahmed · Missouri University of Science and Technology

    Hi  there,

    Also see these articles to understand the relationship between these two tests and their comparisons.

  • Frank Sinclair added an answer in Monolayer:
    What is space group of 2x1 or 2x2 supercell of 1T-MoS2? I want to get 1T' phase of monolayer MoS2, any help please?

    We can get 1T MoS2 from monoclinic C2/m space group... Its unit cell has 3 atoms(one Mo and two S). To get 1T' phase from 1T-MoS2, we need to make the unit cell double (supercell ). I have lattice constants of that 2x1 supercell but I am not finding space group to make the unit cell double. Can anyone help please?


    Frank Sinclair · Applied Materials

    I thought the 1T' variant  was a mono or bi-layers, with no periodicity normal to the surface.  As such, there is no 3D space group, only a 2D space group.  Traditional MoS2 crystals come in the C6/mmc 3D space group, which projects as a p3m1 2D space group.  There is also a rhombohedral MoS2 crystal with R3m 3D space group, which has the same basal plane 2D symmetry, p3m1.  If you send me an email at frank_sinclair@amat.com, I'll send you my sketch and the references I used.

  • Syed Beenish Rufai added an answer in Bacterial DNA Extraction:
    How do you get a pure high concentration of DNA from M.Tuberculosis culture?

    I am participating in work needing a pure DNA of M.T . The problem that we face is with regards to purity and concentration. Anyone have an idea?

    Syed Beenish Rufai · All India Institute of Medical Sciences

    If you need a good concentration of DNA you should culture MTB isolates on L-j medium. After obtaining sufficient growth you can take loopfull of colonies and can proceed for DNA -isolation either by chloroform isoamyl alcohol method or by sonication method. This way you can get good yield of DNA. If you need protocol of CI   method let me know will be glad to share.

  • Iolanda-Gabriela Craifaleanu added an answer in SAP2000:
    What is the instruction for assigning two different stiffnesses in two directions in SAP 2000?

    I am modeling a building in SAP2000 software. The stiffness I have to assign in X direction is different from the one in Y direction. Does any one know how I can assign these two numbers to my building as stiffness?

  • RICK WEB asked a question in Optimization Methods:
    How to find out what optimization method apply to a fractionator crude distillation column?

    I want to find a model to optimize the production of nafta in a distillation column, either athmosferic and vacumm column, using artificial intellingence like ANN, and GA. Any advice?

  • Stephen Crothers added an answer in Black Body Radiation:
    Why is the energy of the CMB missing?

    The energy of a CMB photon when released is given by Planck constant times frequency; and also at arrival. Therefore, as frequency decreases with expansion, the energy at reception is S times lower, being S the space expansion since then. As S is around 1000, the CMB photons arrive with an energy that is only 1/1000 of their original energy; where is this huge missing energy?

    Reasoning in a different way, the energy density of a black body radiation is proportional to the 4th power of temperature, which shifts inversely to space expansion; so the energy density decreases with the 4th power but space expansion only accounts for the 3rd power decrease.

    What happens here? Is this a problem of missing energy? Or is this evidence that there is no conservation of energy over time?

    Energy conservation is a property of mechanical interactions that was assumed as a fundamental law; truly, we only have evidences of this law in interactions, but not through time with the accuracy required for applying it at cosmic scale.

    Conservation laws presume and imply an invariant, static, universe; but the universe is not static.

    What do you think? Is energy missing in cosmic radiation or the validity of conservation laws over time needs to be analyzed?

    Stephen Crothers · Alpha Institute of Advanced Study

    Robert Watson,

    It is evident by your remarks that you don’t know what a blackbody is. In the case of a blackbody there can be no conduction or convection. If a conduction path is present there is no blackbody. Blackbodies can only exchange energy by absorption and emission, at thermal equilibrium within an enclosure. Under such conditions Stewart’s Law applies. To maintain them at 4K temperature the Planck LFI 4K loads where fixed to the 4K shield of the HFI by means of steel screws and washers, thereby producing conduction paths, and so the loads do not function as blackbodies. Thus Planck has no blackbody reference loads. I suggest that you actually study the design of the Planck satellite.

    As I said before, you don’t know what a dead black is. I suggest that you go and learn about them. The wings of the Monarch butterfly are also dead black in the infrared.

    Contrary to your claim, the existence of the dipole signal at L2 does not imply the existence of a monopole signal at L2. Modelling signals together in an infinite series of spherical harmonics does not make them have the same physical source or imply physical existence of any other of them. It is a scientific fact that no monopole signal has ever been detected beyond ~900km of Earth.

    The WMAP and Planck images are not unique and are not the same. One can generate as many different anisotropy maps as one pleases. Consequently such maps have no scientific significance. The WMAP team even inverted signal, which amounts to making the galactic foreground cooler than the alleged CMB. Inverting signal is inadmissible.

    Contrary to your claim, blackbody thermal emission cannot be generated by plasma, dense or otherwise. All gases and plasma emit only in narrow bands. A blackbody spectrum is a continuous spectrum. A lattice is required for the production of a continuous thermal spectrum, and a lattice requires condensed matter.

    Contrary to your claim, water can in fact, under steady state conditions, emit microwaves at an apparent temperature of ~3 K. This is due to the hydrogen bond. This temperature is apparent because Kirchhoff’s Law of Thermal Emission is false and, consequently, Planck’s equation for thermal spectra is not universal (it only applies to a truly black material such as soot, at thermal equilibrium within an enclosure). It’s obvious that you have not studied the paper I cited. Here it is again:

    "The Theory of Heat Radiation" Revisited: A Commentary on the Validity of Kirchhoff's Law of Thermal Emission and Max Planck's Claim of Universality, Progress in Physics, v. 11, p.120-132, (2015),

    There is nothing circular in my arguments about the Big Bang creation myth. It is a creation myth and therefore not science. Here is a detailed analysis:

    Crothers, S. J., General Relativity: In Acknowledgement Of Professor Gerardus ‘t Hooft, Nobel Laureate, 4 August, 2014,

  • Kaushal Jha added an answer in Luminescence:
    When we excite an ion with 379nm to obtain emission at 550nm. Is this a Down conversion emission?

    Because in some papers they diidn't denote as Down conversion instead they use the the term Luminescence with 379 nm excitation, although they use the term upconversion for the 980 nm excitation for the same 550 nm emission...here i m talking abt Er3+...Pls clarify my doubt

    Kaushal Jha · Delhi Technological University

    this is basically a down shifting process, not down conversion process. Generally, down conversion takes place when there is emission of two or more low energy photons when excited via one high energy photon as defined by "Sohan Hazra". It is a luminescence process simply (down shifting rather than down conversion)

  • Mollah Mesbahuddin Ahmed asked a question in Operations Research:
    Is there any method to find the optimal solution without finding the initial basic solution in solving the transportation problems ?

    Operation Research

  • Joseph Skulan added an answer in Infectious Bone Diseases:
    Are there any new serum inflammation markers for diagnosis of bone infection?

    In addition to the traditionally used WBC, ESR and CRP, are there any new serum inflammation markers with higher sensitivity for diagnosis of bone infection?

    Joseph Skulan · Elemental Biomarkers LLC

    If the infection is accompanied by bone mineral dissolution, it should produce measurable changes in the calcium isotope composition of serum and urine.


    Gordon et al. Predicting multiple myeloma disease activity by analyzing natural calcium isotopic composition. Leukemia. 2014 Oct;28(10):2112-5. doi: 10.1038/leu.2014.193. Epub 2014 Jun 12.

    Channon et al. Using natural, stable calcium isotopes of human blood to detect and monitor changes in bone mineral balance. Bone 2015; 77: 69-74; DOI: 10.1016/j.bone.2015.04.023.

  • Muhammad Farooq Ahmed added an answer in Dam Engineering:
    What is the good method to use in order to estimate the sediment retention time in dams?

    I want to calculate the sediment retention time in dams, can you help me to find different methods to use.

    Muhammad Farooq Ahmed · Missouri University of Science and Technology

    Hi There,

    I found this article very helpful to get some useful information about the topic

  • Jijumon. A.s asked a question in Pellets:
    After pelleting down the cells for plasmid isolation or protein purification ,I found there are black substances along with the white pellets ??

    After pelleting down the cells for plasmid isolation or  protein purification ,I  found there are black substances  along with the white pellets usually in the bottom part showing higher molecular weight  Can anyone please explain what these black substances are ??

  • Jill Miotke added an answer in Cryosectioning:
    How can I prevent detachment of retina from choroid during cryostat sectioning of human optic nerve head?

    Hi, in my project I am doing cryostat sectioning (Longitudinal section) of human optic nerve head. In cryosection, I have to keep all the three layers (retina, choroid, sclera) attached together but after cryosectioning I find the retina detached from choroid or huge gap between retina and choroid. I think this problem might be due to embedding problem because when I embed the tissue in OCT medium I can’t keep the retina completely attached to choroid. It would be highly appreciated if you have any suggestion to solve this problem.

    Jill Miotke · University of California, Irvine

    Dear Mohammad,

    I second what Joana and Virginie say about carefully removing the lens!  That is probably the most difficut part of preparing the eye cup-the vitreous stays gooey, since it has so much carbohydrate.   I also puncture the mouse eye thru the cornea before putting it in liquid, even if I have fixed the tissue by transcardial perfusion.

    Good Luck-


  • SUNIL KUMAR YADAV added an answer in Word 2007:
    Shortcut key to merge some cells in table & to split the same!
    Can anybody suggest the shortcut keys for Merging & splitting the cell in MS word & MS Excel?
    SUNIL KUMAR YADAV · Jawaharlal Nehru Krishi Vishwavidyalaya

    THANKING U SIR...................

  • Scott R. McCleneghan added an answer in Fusion:
    In plasma fusion machines, it seems many of the problems occur because of the electrons in the plasma. Any reason they aren't stripped out?

    Would many of the issues that occur in containing a plasma for fusion not be eliminated if the plasma consisted of nuclei only?  Indeed, wouldn't the simplest plasma be homogenous, say just deuterium nuclei only?  I understand that a D-D fusion reaction does not produce as much direct energy as, say, a D-T reaction, but would there be a sufficient energy savings, overall, due to the simplicity of containing a homogenous plasma, outweigh the lower direct output?

    Scott R. McCleneghan · Dauntless Ventures, Inc.

    Herr Müller, Danke schöne.  I am understanding now the reason why this isn't done.

    Mr. Nicolas, Arigato.  Yes, I'm aware of the Farnsworth/polywell fusor.  (I've thought about making one for my high shool engineering lab).  I found it when I was researching reactor designs.  If it can be made to work economically, that would be big.  On the DPF device, the chamber is filled with fusible material, it's "pinched", the reaction occurs in some micro- to milliseconds, and then chamber must be reset for another "pinch"?  Is that how I'm reading it?  How frequently can this cycle be done?

    Mr. Cobb, Thank you.  I understood before I asked the question that confining a homogenious plasma would be difficult.  The authors you listed, are their calculations all for Tokomaks, or are they looking at alternate reactor designs?  If so, what other design configurations?