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  • Rahul Krishna added an answer in Graphene Oxide:
    Why the yellow-brown colour of the prepared graphene oxide by modified Hummers method turns to dark brown after washing with water?

    Why the yellow-brown color of the prepared graphene oxide by modified Hummers method turns to dark brown after washing with water?

    Rahul Krishna · University of Aveiro


    First of all, at the time of synthesis the acidic mixture contains lots of MnSO4 impurity. The color of this specie is pale pink ( especially, in case of tetrahydrate ). So, initially due to this GO looks more bright and faded white. After the continuous rinsing this impurity get rid of along with some labile oxygen functional groups. Moreover, at the time of washing dissolved oxygen of the system (either in acidic water or between in the layers of GO) also deprive/reduces. Due to this some how crystallographic lattice spacing (001) also decreases as compare to original exfoliated system after adding of water.... simply means reduction process happen which finally led the color change as per pi conjugation and chromophore theory. 

  • James Wilson added an answer in Cardiology:
    Does anyone have experience with supernormal conduction and can recommend a review or an example?
    I would like to read a review and to see an example.
    James Wilson · Texas Heart Institute

    Dr. Mehdi Razavi at St. Luke's in Houston may be able to help you. you can call him at 713 417 9161. He's pretty sketchy about answerin because he spends a lot of time in the lab.

  • How should Adolf Eichmann have been punished?

    How should Adolf Eichmann have been punished? The question assumes that punishment is an appropriate response to his crimes.  Hannah Arendt agreed with the Supreme Court of Israel that Eichmann should be put to death, though her reasons were quite different.  She concluded her study of his trial, ‘Eichmann in Jerusalem’, with the following words of condemnation: ‘no one, that is, no member of the human race, can be expected to want to share the earth with you. That is the reason, and the only reason, you must hang’.  She would have condemned him to forfeiture and elimination rather than punishment.  Suppose Eichmann had not been sentenced to death.  If he is to be punished, how is it to be done? This is the challenge implicit in Arendt’s final condemnation. If he is allowed to live, how are Eichmann's judges, the correctional officials, prison warders and the broader community which they represent, going to ‘share the earth’ with him?   Eichmann would probably have made a compliant prisoner.  He was compliant with his interrogators: Arendt records that he told them that, ‘he would like to find peace with [his] former enemies’.  If he is not to be executed, must the criminal justice system offer him opportunities for redemption, reconciliation and eventual release?  

  • James F Peters added an answer in STL:
    Is there any program for 3D tessellation based on arbitrarily shaped polyhedra?

    I would like to tessellate 3D shapes (think of STL files) using arbitrarily shaped polyhedra. Is there any program that could be used for that purpose preferably an open source program?

    James F Peters · University of Manitoba

    This is a good question with many possible answers.

    A good place to start  is

    A. Abdul-Rahman, The design and implementation of a two and three-dimensional triangular irregular network based GIS, Ph.D. thesis, University of Glasgow, 2000:


    See Fig. 5.6, page 83, for sample tessellations produced by the TIN software described in this thesis.

    For the mathematics plus lots of good examples of 3D tessellation, consider

    S. Ghosh, S. Moorthy, Three dimensional Voronoi cell finite element model for microstructures with ellipsoidal heterogeneties,  Computational Mechanics 34, 2004, 510-531:

    See Fig. 3, page 515, tessellated domains yielding Vononoi cell meshes for randomly distributed spheres of the same size and randomly distributed ellipsoids of different sizes.

  • James Wilson added an answer in Amyloidosis:
    How do you measure the ratio of voltage and wall thickness in myocardiopathies?

    2014 ESC GUIDELINES OF HYPERTROPHIC MYOCARDIOPATHY SAYS: Differential diagnosis between HCM and cardiac amyloidosis is aided by measuring the ratio between QRS voltages and LV wall thickness.

    I ask: How do you do the measure of ratio of voltage and wall thickness in myocardiopathies? The sum of all voltages of all leads (Positive and negative deflections)? Only precordials? Only frontals? Ratio by: Septal and wall thickness? LV mass? And the value: <1; < 1,5? Other?

    James Wilson · Texas Heart Institute

    great question but there is no answer. Cardiomyopathies differ in their histology. Some have hypertrophy, some are infiltrative. Both will have increased wall thickness. We now have the capability to differentiate with MRI. This is a study that needs to be done. At what point of deviation from echo wall thickness and ECG Voltage (preferrably using Cornell) should we raise concern about infiltrative disease. Of course the question may be obviated by the ESC recommendation that MR is our first diagnostic imaging study.

  • Does anyone know some work that would help me to study social representations in images?

    I'm looking for examples where social representations embodied in visual cultural products were studied. I found very few examples. Does anyone know some work  that help me to study social representations in  images? Is someone doing  a research of this kind?

    Francisco L. Borrego Gallardo · Universidad Autónoma de Madrid

    Hello, Carolina:

    I can recommend you the classical -and for that a little dated- work of the French semiologist Roland Barthes, whose studies of, for example, advertising and media in their social contexts are of paramount importance. They are more or less easy to obtain.

    I can also recommend you two or three journals where it is possible you find several papers of interest: 'Semiotica' (http://www.degruyter.com/view/j/semi), 'The American Journal of Semiotics' (http://www.pdcnet.org/ajs/The-American-Journal-of-Semiotics), 'International Journal of Signs and Semiotic Systems' (http://www.igi-global.com/journal/international-journal-signs-semiotic-systems/41024) or 'Visio' (https://aisviavs.wordpress.com/publications/journal-visio/).

    I hope this can help you.


    Francisco L. Borrego-Gallardo

  • John Cook added an answer in Applied Linguistics:
    Can anyone suggest qualitative analysis software to analyze video/audio interactions?

    Our research team has hours of video and audio of classroom interactions that we have been transcribing onto a word doc (as well as using Inqscribe). We are seeking a way to connect video, transcriptions and coding in one place (for several research team member to use). What do other researchers use? (seeking insight from Applied Linguistics, Education, Anthropology)

    John Cook · 5 Deep Limited

    I use HyperResearch which combines docs, images video - good categorizing and coding. Multiple and team available. http://www.researchware.com/ 

  • Linh Nguyen asked a question in Spectrum:
    How to calculate Fourier Spectrum?

    Please suggest to me some ways to calcluate Fourier Spectrum!

  • Ella Pavlotskaya added an answer in Linguistics:
    Which modern language uses a partially syllabic writing system?

    Please if you have any idea about the syllabic writing system, share your knowledge
    Thank you in advance

    Ella Pavlotskaya · Florida Hospital, Tampa

    What about modern Hebrew? 

  • James Wilson added an answer in Diagnostic Imaging:
    Do you have tips and tricks how to safely close a post-MI VSD in a cathlab?

    There are still many limitations in a transcatheter closure of post-MI septal defect including the rigid delivery sheath that could tear the borders of VSD or dislocation of sheath into the right ventricle after wire removal. Also, currently available occluders are suboptimal.

    James Wilson · Texas Heart Institute

    I would echo the comments above. keep the wire covered with a swan to avoid further fissuring of the defect. Most importantly, have a pediatric interventionalist with you as they are more experienced and can troubleshoot when things go wrong.

  • Ella Pavlotskaya added an answer in Phonetics:
    Can anybody suggest any of the latest articles on Brand Name and its influence on consumer memory and purchasing?

    My research will be about impact of brand name on consumer choice and memory. I would like to examine our local consumer's willingness to choose specific product depending on the brand name and which brand names are easy to remember. I have already found some articles linked with phonetic symbolism and would like to include them to my research. However, I have some difficulties with methodology of my research and need some of the latest articles on this topic. I would be very gratefull if you could share some of them. 

    Ella Pavlotskaya · Florida Hospital, Tampa

    Sound symbolism effects across languages: Implications for global brand names

    L. J. Shrum a,⁎, T. M. Lowrey a, David Luna b, D. B. Lerman c, Min Liu a

  • Rahul Krishna added an answer in Gold Nanoparticles:
    What happens when an organic molecule containing carboxylate group exposed to sunlight irradiation ??? What kind of mechanism is going on??

    i am using some organic molecules containing NH2 and COO group for the preparation of Gold nanoparticles under sunlight irradiation. when the reaction proceeds, whether the molecules COO- group is cleaved or not ???? As per photochemical synthesis this cleavage is possible in this case how it happens ??? can anyone help me !!!!!

    Rahul Krishna · University of Aveiro


    Suppose if you are using amino acid such as L-lysine or Glysine the nothing will  break simply. For more detail please read photoreactions Norrish type I and II. 

  • Larbi Gueraiche asked a question in Infrared Detectors:
    How to quantify the thermal dissipated energy during SHPB impact test ?

    During impact in SHPB tests, an increase in temperature was observed. The dissipated energy affects the viscoelastic behavior of composites especially when the released temperature attains the Tg of the matrix. Does anyone know any high speed infrared detector (camera) which is able to monitor temperature dissipation during impact tests or  quantified the dissipated energy due to damage?

    Your help will be very appreciated.

  • Dominique Liger added an answer in Chronic Leukemia:
    What is the best method for laboratory examination of ALL and CML? I means ABL-BCR Fusion?

    I can't get good bands in electrophoresis in nested-PCR, how can I take it?

    Dominique Liger · Université Paris-Sud 11

    Hi again,

    I'm not in the field, I'm afraid... What primer sets are you using for your PCR? Do you check cDNA integrity of your samples?

    I think these could also help:



  • Which sociologist in classical term (1700-1900) was interested in natural sciences like ecology?

    Is there any study has been done related this issue?

    Ugur Kezik · Istanbul University

    Thank you all of you such as invaluable contributions. Its really help me a lot AND

    Than you Dear Howard Doughty for your interest. Whether Dear Edward imply  "La March" or "Lamarckian" the most important thing is how he contribute and what we understood. So, "nobody wasn't born yesterday" :) Finally, both of you are precious Scholar. And you are really good at scientific cliffhanger...As a result, I am looking forward more golden comments and advices as I need...

  • Can anybody suggest me research articles on dislike button/ dislike article/ dislike post etc.?

    Can anybody suggest me research articles on dislike button/ dislike article/ dislike post etc.?

    Thank you!

    Fabio Gasparetti · Università Degli Studi Roma Tre

    like/dislike user behaviours strongly depends on the category of items under discussion. For example Chang and Sun studied a prediction model of likes of friends' checkins on social network in the following paper:

    Location3: How Users Share and Respond to Location-Based Data on Social
    Fifth International AAAI Conference on Weblogs and Social Media

  • C. Nunan added an answer in Narrative:
    How complex is narratology in Detective/Crime Fiction?

    There's the narrative operations of the detective, the clues that refer to the unknown but soon to be signified story of the villain, and all the while the reader is constructing their own narrative about 'what happened'. Contemporary Detective Fiction writers narratively construct - through cultural discourses, plot, themes and characterisation - stories that are intended to influence their readers.    

    C. Nunan · La Trobe University

    Thank you Aysha - what a marvellous explanation of innate flawed behaviour as different from choice and agency, in literature. I'm grateful for your teaching. Hopefully I can represent this challenge in my novel. 

  • J. Hemberger added an answer in Peptides:
    Can any one suggest me the perfect storage condition&Method of Synthetic peptides?

    I Need to store synthetic peptide for years, whats the condition and storage method for this, some peptide degeneration takes place even in moisture free -200c. can you suggest any effective storage methods?

    J. Hemberger · Technische Hochschule Mittelhessen

    I can confirm that best storage condition is the moisture-free, lyophilized form. For longterm storage we use argon atmosphere and a temperature of -80 degree C. Important: avoid repeated freeze-thaw-cycles, therefore use small aliquots for freeze drying.

  • Ammar Bader asked a question in Camels:
    Could mushrooms survive on animals stools?

    I have found 2 mushrooms in Makkah, Saudi Arabia..I was very astonished to see these mushrooms in a very poor soil !! after analyzing the habitat, I have found high rate of camels stools in this area where these mushrooms are growing.. could mushrooms survive on animals stools?

    please could anybody identify these mushrooms?   

  • Do you have any experience with this pathology?

    Rupture of ventricular septum, Papillary muscle and free ventricular wall after myocardial infarction in the same patient .Did your patient survive? Usually these patients don't survive.

    James Wilson · Texas Heart Institute

    It has to be a perfect storm. The right time, the right circumstance (so that you can support them) and an experienced surgical team. At the house that Cooley built, we have a wonderful surgical service that is incredibly responsive but the planets must be aligned to be successful. The OR is open. A surgeon is free and the rupture is discovered rapidly. Any breakdown in the chain is failure. When Dr. Cooley first studied their experience with these patients, the mortality was 50% and they decided not to publish. A mistake as these are still the numbers that we live with.

  • Is the regression of modern science a law of development of human society, or is it a consequence of the wrong policy in the field of science?
    If we compare the situation, say in Physics, which was 100 years ago and at present --- there is no doubts, we lost the rate of development of this science.
    What is the reason? Why somebody from another topics at the RG presented as the greatest invention of last time the Internet ? --- although a computer with the Internet is nothing else like a compound of telephone, TV, typewriter and adding machine, and the invention each of the component has much greater importance that the idea to unite them in one machine. Why last decades we do not observe great scientists and great discoveries? Can be a reason that the governments of the leading countries of the world (not speaking about others) do not support properly scientists? Can be a reason that to be scientist now means much less influence and more low status than before? For the proof of the Riemann hypothesis the US institute promises award in 1 million of dollars. The most average Hollywood actor earns more per year, not to mention not the best footballers. Why scientific discoveries are not so valuable at present?
    Dejenie A. Lakew · John Tyler Community College

    Dear Eugene,

    My comments were not towards a specific country and likewise is the question. But what is the contemporary name of science in Russia? By the way USSR is the old name which is no more in use, it is called the Russian federation or simply Russia  today? I am not right dear Ekaterina ? 

    With kind regards,


  • Ferdinand Schmidt added an answer in Global Warming:
    Does anyone know of any new technological advances that could possibly be used to enhance the thermal performance in older buildings?

    I am researching about alternative methods to solve thermal problems in historical buildings. Many older buildings in Australia were built in a style with out consideration of the climatic conditions. This reason as well as the increase in global warming has caused indoor temperature to become very uncomfortable for its residents. I am aware of the current solutions being used to solve these issues, such as sarking, insulation, double glazing etc. I am trying to find Innovative options that could provide a long term solution in addition to contribute several other benefits to the existing structure. Does anyone know of any technological advances of any kind, that could possibly be used  in construction?  Any help would be greatly appreciated. 

    Ferdinand Schmidt · Karlsruhe Institute of Technology

    Within the field of phase change materials (PCMs) mentioned in previous answers, I would like to point you to the technology of micro-encapsulation of paraffines that enables integrating PCM into construction materials such as plasters. The technology was developed by a research institute in Germany (Fraunhofer Institute for Solar Energy Systems) together with the chemical company BASF, and is marketed under the brand name "micronal" (see e.g. http://www.micronal.de/portal/load/fid443847/BASF_Micronal_PCM_Brochure%202009_English.pdf ).

    What PCM does is to increase the thermal mass of a building in the temperature range around the melting point of the material. Therefore, the prerequisites for its effective use (in preventing overheating of buildings) are:

    a) night temperatures are low enough to allow solidification of the material during night time

    b) the thermal mass of the building (or at least the fraction of it with a good thermal coupling to indoor air) can be significantly increased => most effective for lightweight buildings!

    c) night ventilation at a high air change rate can be achieved to transfer the heat of solidification of the PCM to the cool night air and thus to release it to the environment.

    If not all of these conditions are fulfilled, "active PCM systems" may be employed to increase the effectiveness of the PCM in cooling the building. One such system consists of a heat exchanger made of capillary tubes (www.clina.de) that is integrated into the plaster layer containing the PCM. The heat to be extracted from the building is thus transferred to a fluid loop that can be connected to a suitable heat sink, e.g. a ground heat exchanger (boreholes). The auxiliary electric power required for fluid circulation can still be much smaller than that of an active refrigeration system, and (perhaps even more importantly) the electric load can easily be shifted to off-peak hours.

    Hope this sparks your curiosity,

    Best regards, Ferdinand

  • Sachin Goel added an answer in Thin Films:
    How to solve time dependent nonlinear PDE??

    I have thin film drainage equations which are time dependent nonlinear PDE and want to solve them numerically. Can someone help me out here? I have tried so many methods to solve it but nothing is working out.



    Sachin Goel · University of Toronto

    Dear Toufic El Arwadi,

    I have attached my equations along with. Can you look into this ? if you do not mind and how I should solve it?


  • John Boswell added an answer in Psychology:
    Who is currently researching the link between Attachment Theory, Substance Abuse, and Loss and Grief?
    I am interested in the link between Substance Abuse, Loss and Grief, and Attachment Theory - and how this can influence the outcome of counselling clients with substance abuse issues.
    John Boswell · Independent Researcher

    Thanks Bubba - I will start reading!

    Happy New Year!



  • A. El kharbachi added an answer in Tritium:
    Why can we use the deuterium retention in tungsten to predict the tritium retention?

    Recently, I have referred to many papers about deuterium and tritium retention experience in JET and TFTR. In these papers, it has been most mentioned that D and T have similar behavior in the first wall of Tokamak, such as the ratio of gas
    retained to the fuel part, but can we just use these experiments' data to infer the connection between D and T retention behavior?

    Is there any theory or study which could explain that?

  • What are the Boundary conditions for a Vibrating Plate Composed of Two Materials?

    For a rectangular plate with one half made of material A and the other half made of material B, what would the boundary conditions be at the interface?

    David Mark Koenig · Corning Incorporated

    Dr. Sadeghnejad,

    Thank you for your response. I assume DoF means degrees of freedom. I do not know what a "slippery" condition is. When you say that I should fix all the 6 DoFs at the interface between the two halves of the plate, again, I do not know what you mean.

    I am numerically solving  

    NL [d4/dx4+2d4/(dx2dy2)+d4/dy4]w + rho*h*d2w/dt2 = 0

    in the interior of the left half (0<x<L/2, 0<y<H) and

    NR [d4/dx4+2d4/(dx2dy2)+d4/dy4]w + rho*h*d2w/dt2 = 0

    in the interior of the right half (L/2<x<L, 0<y<H) of the plate.

    At the outside edges I am applying w=0, dw/dx=0 and dw/dy=0.This should be sufficient for a constrained clamped plate were it not for the fact that the plate has two halves.

    At the interface, where x=L/2 and 0<y<H, and where you say that I should fix all the 6 DoFs, what specifically should the boundary conditions be?

    For example, should I say that  w(L/2-,y)=w(L/2+,y) for 0<y<H

    and  dw/dx(L/2-,y)=dw/dx(L/2+,y)? If this were a heat conduction problem I would instead say   kL dw/dx(L/2-,y)=kRdw/dx(L/2+,y).

    Could you therefore expand on your comment?

    Thanks again for your help.



  • Pierre Béguin added an answer in cDNA:
    I have a 11kb plasmid with a 6kb cDNA. Now I would like to construct a mutant plasmid with a point mutation. Is there any special method?

    I have tried several polymerase including fusion and KOD. Do you have recommendations concerning the annealing temperature and the PCR cycles? 

    Pierre Béguin · Institut Pasteur

    I have had success using the Quikchange methodology (see Agilent web site), but only with Pfu turbo, not with Phusion. If it doesn't work (your plasmid is fairly big), make two overlapping PCR fragments bearing the desired fragments, fuse them by PCR using the distal primers and reclone them in your vector.

    Good luck

  • James R Knaub added an answer in Survey Research:
    How to calculate sample size for survery research?

    what is the simplest formula for calculating the sample size in survey research?

    James R Knaub · Energy Information Administration

    Thank you. I hope this is helpful.

    Note that in every case, some idea of the variance for data of interest has to be estimated, 'guessed' (Cochran, p 77), or assumed first. Cochran notes four ways to do this, including a pilot study or previous similar data. You may have to do a sensitivity analysis (worst case - best case soft type of analysis) first. Other survey statistics books, such as Kish or Lohr, might help.

    Note also that this needs to be done individually for every (important) variable of interest (item/question on your survey). 

  • Chaminda Wijethilake added an answer in NVivo:
    Can you suggest me some ideas about which tools in NVivo should be used to support relationships in a qualitative framework?

    A reviewer of our journal paper has suggested that “Nvivo has tools for the construction and testing of answers to research questions”. The reviewer expects a discussion on which the relationships in the (qualitative) framework are in fact supported by the NVivo analysis. I’m not sure what the reviewer is referring to here. Can you suggest me some ideas about which tools in NVivo should be used to support relationships in a qualitative framework?

    Chaminda Wijethilake · Macquarie University

    Thank you very much Lluis. Your links are very helpful.