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  • Pauf Neupane asked a question in Lammps:
    How can I perform Gibb's ensemble molecular dynamics simulation in Lammps?

    I am using lammps for md simulation. I wondering if there is way for md simulation in Gibb's ensemble. One way lammps manual suggest is to use " fix gcmc command " which requires chemical potential to be known. I would be grateful if anyone  could suggest me the way when chemical potential is not known. I am particularly interested in calculating vapor pressure in liquid- vapor phase coexistence system. 

  • Wolfgang F. Schwarz added an answer in Drama:
    Why is writing drama on the decline?

    Novel has considerably replaced drama. Some amount of drama is found only in a different genre - film. I think Television, Video and Film restrain people from going to the theatres. Theatre gives enormous scope to dramatic literature which other media cannot. I would like to know and be connected with modern English playwrights in Britain and USA. Some experiments are made in India, but they are not worth the salt.

  • Azzam K Almosallami added an answer in General Relativity:
    Universe is static!!! Yes or no?

    Space of Universe is static! Yes or no?

    Question: Are there any observations that do not fit into the model static space of Universe, are there any theoretical obstacles to the existence of such a model?

    I assume that the Universe is eternal, infinite and static, it is not expanded and not curved, it is possible to construct a preferred inertial frame of reference in which the CMBR is most isotropic. The matter in this space evolves, but the average density of matter and energy (in large enough volumes) fluctuate within a rather broad range.
    The light in this model is "tired", the speed of light depends on the optical density intergalactic medium. Gravity is also "tired" t.i. weakens a little faster R2. The energy of destroying matter goes into the surrounding vacuum. The excess energy from the vacuum give rise to new particles of matter.

    I state that all the observed cosmological effects can be explained in such a Static Model of the Universe.
    See attached "Basic_Cosmological_Formula_1_En.pdf"

    Dear colleagues, I do not ask, what are the problems faced by other theories (though I would be interested in your opinion on that. The General theory of relativity is not applicable to the entire space of the Universe).

    Azzam K Almosallami


    I can reply to your post simply;

    At first your theory and the theory of quantum gravity are proposed basis on objectivity and continuity in SRT which is depending on the reciprocity principle. Objectivity and continuity working well according to Galilean transformation when t'=t. Now when t' not equal to t objectivity and thus continuity not working.  Instead of objectivity and continuity, it must be the Copenhagen school, which is leading to the wave-particle duality and the uncertainty principle. Now in order to not make my post long, I give you a thought experiment London-Paris problem, and can you tell me if the velocity of the plane is 0.87c and if the observer on the Paris on the ground now sees the plane on Paris according to his time t, then for the observer on the moving Plane is the Plane on Paris now, and according to his time t' what is his time? is his time t'=t???

    This is the thought experiment, and then after that we discuss.

    So do not compare my theory with your theory which was built basis on objectivity and continuity, in order to prove your theory, you must prove at first the reciprocity principle in SRT in order to prove the objectivity and continuity.

    Do not propose objectivity and continuity in nature implicitly, and then build all physics according to that, and because of that you propose dark matter/energy in order to fix data according to GR!!!! 


    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: This diagram illustrates a thought experiment debated in one of the RG discussions about the issues around the concept of relative simultaneity ( https://www.researchgate.net/post/Is_relative_simultaneity_a_misinterpretation_of_Special_Relativity ). The experiment was defined by Eric L. during an exchange of replies with Azzam A. who suggested initially a similar idea. With the notations adapted to match my diagram here, a simple definition addressing the current state of the argument would be : - - This thought experiment deals with three clocks (one in London, one in Paris, one in the Airplane). For simplicity we assume that London and Paris are stationary with respect to an inertial frame K, and the Airplane is another inertial frame K' moving with constant velocity v relative to K. The Airplane, at his own coordinates of system K' (x0'=0, t0'=0) , starts moving from London which has the K system coordinates (x0=0, t0=0), and arrives in Paris at the K system coordinates (xP > 0, tP > 0) . The observer in Paris will use the Lorentz Transformation to obtain the time tP' indicated by the clock in the Airplane when it arrives in Paris, and the observer in the Airplane will use LT to obtain the time tP indicated by the clock in Paris. It is claimed that in both calculations, the relation resulted is tP′ = tP/γ . - - - - - - - - - - - - - - - - - - - - - The diagram shows that the claim is incorrect, as the observer in Paris evaluates the LT time differently from the observer in London. The initial discussion omitted to assign a coordinate system to the observer in Paris, assuming incorrectly that the observer in Paris would be just fine only having a clock and just relying on London's coordinates for calculations. However, we argue that Paris should have a full coordinate system and it should evaluate the whole motion of the Airplane, from the very moment of its start from London to the moment it arrives in Paris. No observer can evaluate the motion of an object using only a clock and only one spatial position of the object given by a remote coordinate system. Also, the LT relations between a pair of observers located in two different frames are not identical to the LT relations between one of those observers in his own frame and any other arbitrary observer in the other frame. Different pairs of observers in the two frames yield different pairs of LT calculations. - - - - - - - - - - - - - - - - - - - - - The diagram will be developed later in a more detailed document and it will be accompanied by a video of a 3D animated simulation.
      Full-text · Dataset · May 2015
  • Rafik Karaman added an answer in Disaster Medicine:
    Do you think terror medicine is a different than emergency and disaster medicine?

    What is the difference terror medicine?

    Rafik Karaman

    Dear Şükran,

    Terror medicine is related to emergency and disaster medicine but focuses on the constellation of medical issues uniquely related to terrorist attacks.

    For more details on this issue you can read the book "Essentials of Terror Medicine"
    Editors: Shapira, Shmuel, Hammond, Jeffrey, Cole, Leonard (Eds.).


    Editorial Reviews
    From the reviews:

    "An international group of authors present the basics of terror medicine. … Practitioners and trainees in emergency medicine, surgery, anesthesiology, and other specialties treating trauma are an appropriate audience for this work … . Administrators with responsibility for acute care programs may also benefit from this background material. … I recommend this resource for practitioners and hospitals serving in the acute care safety net." (David J. Dries, Doody’s Review Service, March, 2009)

    “The latest single source reference to address the multitude of issues that arise in our fairly elementary experience in disaster preparedness and response related to terrorist acts. … The challenge for readers … is the applicability of the lessons from countries where terrorism is a daily concern to a country in which even the memories of September 11 have dimmed. … Essentials of Terror Medicine does a nice job of consolidating and distilling important and practical information … with a truly qualified list of contributors.” (David V. Shatz, The Journal of TRAUMA, Vol. 67 (6), December, 2009) 
    From the Back Cover
    A new field of medicine has emerged as a result of the global proliferation of terrorism. Terror medicine is related to emergency and disaster medicine but focuses on the constellation of medical issues uniquely related to terrorist attacks. The field encompasses four broad areas:


    Incident management

    Mechanisms of injuries and responses

    Psychological consequences.

     In Essentials of Terror Medicine, these core concerns are addressed by a distinguished international authorship that has been brought together by the three editors of this volume, who themselves are recognized experts in relevant disciplines: Shmuel Shapira, epidemiology and hospital administration; Jeffrey Hammond, trauma surgery and emergency response; Leonard Cole, bioterrorism and public policy. Moreover, many of the book’s 35 contributors have had immediate and extensive experience in the medical management of terrorist attacks.

     The book provides insightful and practical information for physicians, nurses, emergency responders, and other health professionals who may be called to service during or after a terror incident. Essentials of Terror Medicine is indispensable reading for the medical community of the 21st century, in which diligence, continued education, and careful preparation for a variety of possible events are a preeminent responsibility.


    Hoping this will be helpful,


  • Daniel Martinez Krahmer added an answer in Lathe:
    I am using A2 steel as my workpiece material. Which tool should i use for doing turning operation in lathe ?

    Also how can we simulate turning operation in lathe using ANSYS?

    Than You

    Daniel Martinez Krahmer

    What hardness have the A2 steel?

  • Michael Hornsey added an answer in Antimicrobial Agents:
    Clinical breakpoints for Chryseobacterium?

    Can anybody suggest were to find existing clinical breakpoints for Chryseobacterium species?

  • Hanane Lamaazi added an answer in Metrics:
    How can i combine more than one metrics in RPL Objective Function ?

    Which lines into MRHOF or OF0 algorithms should i change to use more metrics than ETX and Hop Count ?

    Hanane Lamaazi

    Thank you Mr Mohan for the answer,  i will read it carefully in order to draw some ideas.

  • Alfredo Pereira Junior added an answer in God:
    What is the origin of the laws and principles of nature?

    More precisely, "what is the origin of the regularities in nature which are represented (or purported to be represented) in our various recognized or accepted laws and principles regarding nature and natural events?" (this is H.G. Callaway's formulation of the original question). Such a philosophical question should be of interest to all scientists. 

    In classical philosophy, there are two ways of answering it:

    a) Looking for an explanation outside nature. The concept of a transcendent God, the creator of nature and its order, explicitly appeared in Thomas Aquinae (the world comes from God and returns to God), Modern philosophers and scientists. It reappeared in the Contemporary epoch as a refusal of Darwinism, and/or related to some interpretations of Quantum Theory;

    b) Looking for an explanation inside nature. Nature itself, being composed of both Form and Matter (Aristotle´s Hylomorphism) produces its order, in a process that has been currently called "self-organizing". In this view, God is not the creator of Nature, but - as in Aristotle´s concept of a First Mover - an ideal of perfection projected by natural beings.

    It is clear that in spite of Aquinae´s affiliation with Aristotle, their philosophies are in opposite position in regard to the question about the origin of nature´s order. 

    Spinoza tried to conciliate both approaches, by equating God and Nature. In this case, God is not conceived as a transcendent being who creates Nature from nothingness, but as a being who is somehow immanent to Nature.

    Plato, before Aristotle, presented a combined solution, assuming both the autonomy of natural principles (Ideas) and a Demiurge who prompts the manifestation of the principles into the world of appearances.

    There is a possible third alternative, advanced by Kant in his cognitive approach to philosophical issues: to assume that laws and principles of nature are 'a priori' forms that the human mind imposes to sensory "matter". However, this alternative is actually reducible to the others. Cognitive forms should be natural or created by God (both possibilities are compatible in Spinoza's approach). For instance, the Piagetian version of Kantism assumes that these forms are biological, deriving from processes of interaction with the physical and social environment - therefore, he was committed to the self-organizing view.

    Alfredo Pereira Junior

    Dear Chris, Very good thoughts, thank you! I guess a photon would never have an idea of God! 

    Do we, human beings, create God and use our creation to effectively drive the evolution of the cosmos to our desired goals? Today we have powerful technological resources to make things happen. Is this an illusion, or should we think seriously about scenarios displayed in science-fiction movies, such as the evolution of the cosmos being driven by the fight for values (e.g., in Star Wars)? It is interesting to note that in Star Wars an ethical value (the Good) receives a physical denomination (the Force).

  • Fa Sultan asked a question in Spectrophotometer:
    Spectrophotometry: Why do we normally measure absorbance ranging from 0 to 1?

    Why is the value in the spectrophotometer in confined between 0 and 1?

  • Martha Brissette added an answer in Virginia:
    Can stem cell implants help schizoaffective disorder?

    Can stem cell implants help schizoaffective disorder?  If so, what is the closest location to Richmond, Virginia?

    Martha Brissette

    thank you for this information.  The research at Johns Hopkins looks promising.  

  • Martín Martínez Villar added an answer in Brain Imaging:
    Does anyone have an idea about segmentation brain tissue MRI images for detecting tumor?

    Hi all, I need suggestions for segmentation method for brain MRI images. In first part of my work, I should have segmentation of brain images and then detect the tumor with my method. Segmentation is an importance part of my work. If anybody is relative with segmentation algorithms, please help me?
    Thanks all.

    Martín Martínez Villar

    Hi Moslem,

    Here is a general and recent review on MRI brain tumor segmentation (Gordillo, 2013). More concrete aspects on segmentation techniques are also disposable on the literature (Balafar, 2010; Despotovic, 2015).


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  • Ahmed Al-ogaidi asked a question in Microirrigation:
    Proceedings of international microirrigation?

    Dear all,

    I am looking for proceedings for all conferences about international micro-irrigation.

    Can anyone help?



  • Claude Pierre Massé added an answer in Mathematical Models:
    Are the laws of physics true by themselves?

    Or are they just mathematical models that are accepted to predict experiments ?.

    Claude Pierre Massé

    It is true that the acceleration is proportional to the force, for velocities very small with respect to the speed of light, and with an error smaller than 0.1%.

  • Jan-Ervin Guerrero asked a question in Calibre:
    Do I need to calibrate a counter electrode?

    Hi, I have a broken platinum counter counter electrode and I'm trying to make another counter electrode out of it. My question sounds silly but do I need to calibrate it? If yes how? And does the size of the counter electrode affects electrochemical measurements?

  • Kourosh Ahmadi asked a question in Species Distribution Modeling:
    Which remote sensing data is suitable for plant species distribution models?

    I need information about RS data for species distribution of trees

  • Claude Pierre Massé added an answer in Quantum Mechanics:
    Help with Feynman's(thought) experiment with electrons?

    I read his description of the experiment but I still haven't understood as to how the results can't be predicted with "classical physics", what I mean is that electron gun which he has assumed throws out electrons randomly and since we do not know the initial conditions( because of randomness) we can't predict the exact trajectory , and therefore we can talk  only of probability, but I see that Feynman says constantly that "we can't really predict where the electron would end up being" but ain't that because of the random nature of electron emitting device??

    Obviously i am wrong somewhere but I can't catch it?

    Any help would be appreciated.

    Now Feynman has constantly  

    Claude Pierre Massé

    The reasons are right, it is a straigtforward consequence of linearity, and it is the basis of Feynman's paths integral.

  • Rafik Karaman added an answer in SPSS:
    Fisher-Freeman-Halton Test

    Dear researchers,

    Does SPSS provide the Fisher-Freeman-Halton Exact Test for contingency tables that are larger than 2x2?
    How can I calculate the Fisher-Freeman-Halton Test by SPSS?  

    Thanking you in anticipation.

    Rafik Karaman

    Dear Hamid,

    With the Exact Tests module installed, the Crosstabs procedure can print the Fisher-Freeman-Halton exact test of independence when the contingency table is larger than 2x2. If Exact Tests is installed, then the main Crosstabs dialog will have a button labelled "Exact". Click this button and then click the radio button beside "Exact" in the "Exact Tests" dialog that opens. Click Continue. Click the Statistics button in the main Crosstabs dialog and then click the "Chi-square" check box in the Statistics dialog box. Here is a sample syntax command with these choices:

    /TABLES=row BY col

    The result labeled as Fisher's Exact test in the output is in fact the Fisher-Freeman-Halton Test. Note that a chi-square value is not calculated or printed for this test, although it was requested by the chi-square check box or the CHISQ keyword. An exact 2-sided significance is printed.


    In addition, attached please find the booklet of IBM SPSS Exact Tests.

    Hoping this will be helpful,


  • Hakeem Ayomi Sanni added an answer in Staining:
    I'm trying to stain cancer cells grown on gel with ethidium bromide&calcien.I'm not too sure if to fix my cells with 4%PFA or ethanol before staining?

    I am trying to stain #ovarian cancer cells grown on gel with ethidium bromide and calcien. I am not too sure whether to fix my cells with 4% PFA or ethanol before staining. Any suggestions will be greatly appreciated

    Hakeem Ayomi Sanni

    Thank you for your earlier response @Sebastian.

    The idea of fixing the cells with 4% Paraformaldehyde/ ethanol is to make sure the cells do not wash off and are still present during the whole process .
    So if I wanted to do this experiment the steps I would follow would be to

    1. Remove media in which cells are initially growing
    2. Wash gently with PBS without disrupting cells too much
    3. Fix with 4% PFA for 10mins at room temperature
    4. Incubate with mix of Calcien-AM and EtBr in PBS/serm free media for 30mins @ 37degrees

    Now my doubts are should i skip step 3 and just go directly to step 4 or what other steps do I need to include so my staining works perfectly.

  • Pauf Neupane added an answer in Lammps:
    What are the tools for the post-processing of LAMMPS trajectory files ?

    Dear all,

    I am using LAMMPS for MD simulation and interested to know the tools for post-processing of the trajectory files. 

    Thank you in advance.

    Pauf Neupane

    Thank you Shahbaz, M. Warrier and Ibrahim

  • Karen Weletyk added an answer in Attachment Disorders:
    Is attachment disorder the environmental root of sociopathy?

    In  Martha Stout's book, The Sociopath Next Door, she writes "Children who suffer from attachment disorder are impulsive and emotionally cold and sometimes dangerously violent towards their parents, siblings, playmates, and pets. They tend to steal, vandalize, + start fires, + they often spend time in detention facilities when they are young + in jail when they become adults, just like sociopaths".

    Is anyone familiar with this phenomenon?

    Karen Weletyk

    Thanks, Anton Tolman, for your suggestion.  I appreciate your help

  • Aysegul Kaymak asked a question in Cardiomyocytes:
    Which company's FBS would you suggest for the proper cardiac differentiation of P19Cl6 cells?

    Hello all,

    I have been trying to differentiate P19Cl6 cells into cardiomyocytes. However the efficiency is quite low. I know that serum plays quite important role for the process. Do you have any suggestions about that? So far, I tried almost every FBS version of Gibco and none of them worked better for me. 

    Thank you very much for your help in advance

  • Abdul Jabbar added an answer in Social Media:
    Hello any body can guide me to books that disscuss new theories in the field of social media?

    hello any body can guide me to books that disscuss new theories in the field of social media?

    Abdul Jabbar

    Have you read the work of Cialdini and influence? Or stephen Dahl 2015?

  • Mohmed el haji Drissi asked a question in International Relations:
    I hope to find co-autor in fields of: migration, social science, international relations, international law?

    researcherس from Anglo-Saxon universities

  • Shahrooz Eftekhari added an answer in Numerical Simulation:
    I have included the details below, anyone could give a hint on how to improve the cl achieved through simulation?

    Dear All, I have been trying to conduct numerical simulation on NACA43012 airfoil, but unfortunately i was not able to achieve verified results for cl, while the answers i get for cd is correct. I am using C-mesh topology with 7 million cells, i prepared the mesh Using POINTWISE software and imported into FLUENT, I achieved cl of 0.04 while the published data is 0.2, and for Cd i achieved 0.0069 which is the same as the published data, i would appreciate if anyone could guide me or give me some hints regarding the uncorrect cl.

    Shahrooz Eftekhari

    Thanks everyone for the comments, Apparently the issue was with the reference number and i changed the reference length and area from 1 to 0.2603 (Area 0f the wing) and 0.3048(Chord of the Wing), now i am able to achieve correct cl while my cd has dropped from 0.007 to 0.005. 

  • Lilliana Ramos-Collado added an answer in Philosophy of Social Science:
    Praxis versus academic noises?

    Karl Marx states in "Theses on Feuerbach" that "The philosophers have only interpreted the world in various ways; the point, however, is to change it." (Thesis Eleven) I must admit that I'm all the more persuaded by that statement as time goes by. When was the last time you heard voices of conviction and righteousness oozed out from academia and how often do you see an academician get his/her hands dirty?

    If you want to get you hands dirty, here's a link:


    Hm, I guess this post so far has not been qualified as a question. So let me ask this: what do you think of Marx's Thesis Eleven in "Theses on Feuerbach"?

    Lilliana Ramos-Collado

    I find Marx's thesis quite clear, so clear that, for me, it needs no extra philosophical qualifications. I see it as a pragmatic call, as a call to action. It is evident that Marx was tired of hermeneutics, theoretical thought, hypothetical mind experiments. The thing is that all can a person do is change the world on the basis of his or her knowledge. There is a great similarity between this thesis and Benjamin's comment on "The author as producer": a writer's work is not only about writing, but about writing changing the means of the production of writing. As a playwright, Brecht —the protagonist of Benjamin's essay— changed the way theatre was produced (conceived, written, acted, staged...), for example. Brecht wanted to use his theater to change how people thought about their lives and make them more politically aware of injustice. In sum, it is our talent that is called to action, that which we do best. And not only our talent, but bringing our talent to change the way it is "produced" so it can go beyond itself.

    Good question, with a twist, of course! Lilliana

  • Rana Momani added an answer in Kurtosis:
    What are the criteria for deciding a normally distributed data?

    I have 3 groups of data A, B,C, each having 10 number of samples. when I analyzed for their Z-values (both skewness and kurtosis), all three groups of data are normally distributed. In Shapiro-wilk test, only group A and C are normally distributed; while in Kolmogorov- smirnov test, only group A and B are normally distributed.

    Now. On the basis of the number of data in each group and all 3 methods of analysis, which one should I have to choose for explanation of the distribution of my data.

    Rana Momani

    Dear Kumari

    Because of small sample size it is hard to test normality as Dr. Amin mentioed   specially using graphical approach, but in this case you might use the normal probability plot if it linear, then your sample is normaly distributed, this link may help you

    good luck

  • António Maximiano Fernandes added an answer in Campylobacter:
    Bacterial RNA extraction during host invasion?

    Hi everyone, 

    I need to extract Campylobacter RNA while infecting amoeba cells. Does anyone know a suitable method or kit for this? My problem is to separate the bacterial RNA from the eukaryotic RNA...i am afraid this could impair my RNAseq analyse (see what bacterial genes are being expressed while Campylobacter is infecting host cells). 



    António Maximiano Fernandes

    Dear seems difficult to do this approach. There is not specific kit to to this.

    My suggestion is:

    First need to separate bacteria from ameba, the can be done by aplying ultrasound (bath).

    • Wash infected cells several time with pbs to remove unattached bacteria.
    • Then put the mixture (eppendorf) in ultrasonic bath for different time
    • Use a filter that allow only bacteria to pass through
    • Use it to extract rna

    * The washing steps is critical

    Boa sorte

  • Rafik Karaman added an answer in Gaussian:
    What are the units of the Hessian in Gaussian?

    In Gaussian, the Force Constant matrix (unweighted hessian) can be found in the formatted check point file. I would just like to double check a few things:

    1) Are the hessian units Hartree/radius_bohr2?

    2) If (1) is true, then to convert into kcal/(mol Ang2) is the conversion constant 627.509/0.280029 correct?

    Thanks for any help. I just wanted to sanity check. 

    Rafik Karaman

    Dear Anthony,

    You are absolutely right.


  • Solomia Fedushko added an answer in Social Media:
    What are the differences between Social Media and Social Networks?



    Solomia Fedushko

    Hi, Farzaneh Sharifi

    Please read interesting articles to understand the difference between Social Media and Social Networks.

    I hope this helps.  Solomia.

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