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  • Can anyone tell me the name of Bacillus sp. which gives orange pink pigment in nutrient broth?

    I have a bacterial isolate which gives bacillus like cultural characteristics on nutrient agar plate and gives orange pink pigment in nutrient broth. what is the tentative identification?

    Faek Abd Alrazaq · Damascus University

    Please tell me what is the bacteria

    I think 16S rRNA is the best way to detect it 

    Good luck

  • Milad Esmaeilbeigi added an answer in DNA Damage:
    Human DNA damage measurement using extracted DNA only?

    I only have extracted DNA from human blood leukocytes. I want to measure DNA damages in these DNA samples. Ideally the measurement will focus on the oxidative damages, but it can be more general. My goal is to relatively compare the damages in these DNA samples, so the absolute amount of damage in each sample is not necessarily a concern. Is there some kind of commercially available assay or PCR kit to do this?

    Milad Esmaeilbeigi · Tarbiat Modares University

    hi, the best method for DNA damage assessment is sigle cell gel electrophoresis(SCGE) or comet assay that in alkaline version can detect both single and double strand breaks in DNA strand. anyway, you can use from PCR method for detection DNA damage.

  • Younes Fathabadi asked a question in Control Systems:
    Where can I solve problems on multivariable control systems find it?


    Where can I solve problems on multivariable control systems find it?

  • What are the best methods for filling in missing values?

    I have a data set of infertile patients and I want to apply machine learning methods later on this. However, some attributes are not completely filled and have missing value. What are the best methods for filling in missed values in data mining?


    Rafael Brundo Uriarte · IMT Institute for Advanced Studies Lucca

    There exists many approach to missing-data imputation and they usually depend on your problem and how your data algorithm behaves. If the features are numeric you can use simple approaches, such as average values and sampling from the feature distribution. In the literature there are thousands of methodologies to do it, I would recommend you to use the Amelia II software, which provides many solutions for the problem.


  • Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Should one consider the C-C Lennard jones interaction for a single layer graphene?

    Sayyed Jalil Mahdizadeh · Ferdowsi University Of Mashhad

    Dear Zacharias

    Do you know that i can do this procedure ( VdW interactions occur only for 5th or higher nearest neighbours of a certain atom of the polymer chain) in LAMMPS ??

  • Do you think gender is a social construction?

    With reference to feminist perspective, do you think gender is socially constructed? Will appreciate your ideas. Thanks everyone.

    Jan Vinita White · Walden University

    Gender is socially constructed.  People often confuse "sex" with gender.  On many applications and forms, there is a question about "gender" with M/F as choices.  This is incorrect. 

    Gender is a role and roles are socially constructed.  As a tribal member, I have studied gender roles among the indigenous peoples of America.  Some tribes have up to four genders and mixed genders [two-spirit people or berdache] are common and accepted... even embraced and revered depending upon the tribe.  I hope you will read about one of the most famous two-spirits, a Zuni named We'wha.  A book was written about We'wha, The Zuni Man-Woman by Will Roscoe. 

    Jan Vinita White, PhD, gerontologist

  • Feng Lin added an answer in Plant Molecular Biology:
    How do genotype my T-DNA insertion Arabidopsis line?

    Hi everybody,

    I now encounter a overwhelming problem about genotyping. after first round genotyping, I selected the positive seedlings,i.e., with FP+RP, no wide type DNA was amplified, with LB+RP, a T-DNA insertion DNA was amplified. OK now question comes. after I select this positive mutant, and got next generation seeds from this plant, and genotyped once again. There is a weak band same as wild type size in mutant. I even changed new primers, and still weak bands. I still selected positive plants without this weak bands, and got seeds from them, and genotyped once again, this weak bands appear gain. I don't know how to deal with. I was crazy. Btw, this SALK line has been reported by others as loss of function, and no band can be amplified in this mutant when genotyping.

    any suggestions will be welcomed!

    Feng Lin · Martin Luther University of Halle-Wittenberg

    yes I used wild-type as control. Btw, this weak bands randomly appeared in different samples, but still could be visuable, not very bright. I will try your method.

  • What are the possible approaches for solid transport computation in turbulent pipe flow and for the requirements necessary for avoiding sedimentation?

    The development of correlations for computing the critical velocity required for avoiding sedimentation in two phase liquid-solids in pipes under pressure was subject of many studies since several decades ago. However, the simultaneous effects of particles size and its distribution, concentration and density of solid particles, liquid viscosity, diameter and slope of upward pipes in turbulent flows look globally a complex issue. What are the possible approaches for these phenomena? New approaches, pertinent references and particularly any pertinent summary about the state of art in this field will be appreciated.

    António Manuel Abreu Freire Diogo · University of Coimbra

    Yes, you are correct, Dear Krishnan. In sanitary sewerage systems, for example, low velocities increase retention time in pipes (and sulfide generation in pipe flow) and sedimentation. Ventilation is fundamental in sanitary sewer systems in order to avoid sulfide generation (H2S), and the subsequent odors, toxicity and … corrosion. These systems are normally conceived by gravity and in open channel flow with pipes partially filled with air atmospheric for ventilation. Pipe flow is as much as possible avoided, and the national regulations and manuals of practice (like ASCE or EPA manuals, for example) establishes additional procedures for sulfide control like air or oxygen injection (in low points of the conduits to guaranty a good efficiency of oxygen transfer), or the addition of hydrogen peroxide, for example. Hot climates, large networks, and pressurized pipes that cannot be avoided due to difficult topographies are critical factors in conception of the systems and sulfide control.

  • Richard Croucher asked a question in Book Publishing:
    Would would anyone like to review my book published today and available from Amazon?

    Publishing your research in scholarly journals: a street fighter's guide by Richard Croucher (2015)  Amazon Books, £7.

    would anyone like to review my book published today and available from Amazon?

    The purpose of this short book is to help all those interested in publishing their research in scholarly journals or who are already doing that and wish to improve their performance. It draws on my personal experience over many years as an editor of scholarly journals, a member of the British Journal of Management’s editorial board, and as the author of over seventy articles in American and European journals. I have ten years’ experience as Director of Research in a large British business school and therefore read and comment on colleagues’ articles on a regular basis. I have published work in business and management, law, education, history and sociology. The book will be especially useful to those people who research in social science, business and management, law, education or history. I provide a systematic and practical set of advice and tips in a grounded way based on my experience and taking a pragmatic rather than a purist approach: hence ‘a street fighter’s guide’

  • Ardalan Amiri added an answer in Cracking process:
    Is it possible to use stress developments of cracked components in IWM Verb?

    In IWM Verb you have to use the stress development of the unbroken component. Are there any methods which allow you to use the stress development of already cracked components?

    Ardalan Amiri · Politecnico di Milano

    As far as I concern in case of FEA software, since the stress calculation and visualization of an already cracked component rely not only on the external variables but also on the pre-defined stress fields as an I.C. referring to the cracked area, then one may look for the availability of such an option in the FEA software environment and/or its documents generally.

    However, I've never personally had the privilege of dealing with that hard core German software IWM Verb so I am not even sure if it uses FEM but I assume its options for pre-porocess loading is so limited based on http://www.iwm-verb.de/scope/ and specially the following phrases in "Computational models" section:

    "Input of an analysis model includes the selection of:
    Structural model
    Loading type
    Crack type
    Crack orientation
    Crack position"

    "Loading for the cracked component is defined by one of the following options:

    1. Load components: these can be tensile force or membrane stress, bending moment or bending stress, internal pressure
    2. One-dimensional stress profile s(x) in the prospective crack plane; here the coordinate axis x points in the thickness direction
    3. Two-dimensional stress profile s(x,y) in the prospective crack plane; here the coordinate axis x points in the thickness direction and the coordinate axis y points in the length direction
    4. Stress profile can be superimposed with load components"

    and I hope their English explains everything about the software ;)

  • Peter T Breuer added an answer in Server:
    What is the Microsoft Windows MultiPoint Server?

    Microsoft Windows MultiPoint Server

    Peter T Breuer · Birmingham City University

    Yes, but what IS it? What, for example, is the "problem" to which it allegedly is a "solution". I don't think anyone asked how much it costs, or how easy it is to use, or how easy it is to implement. And why are we implementing it? Aren't we paying money for it .. why would we pay for something that is not yet "implemented"? And while it's nice to know that it gives "teachers" the "right" "tools", I don't think anyone asked to whom it "gives" anything, and certainly not whether what it gives are "tools" or "headaches". What does it do outside of an educational setting? Who mentioned "educational setting" anyway? Not me, not you. So nobody asked that question either.

    (and why doesn't the OP ask microsoft - they have plenty of user forums and helpdesks, and salesmen).

    I hope you enyoyed my solution that seamlessly connects many RG users to a central theme or concept. I'm thinking of calling it a "multipoint service". What do you think of the name?

    [PS .. for a small fee I will happily translate that meaningless garbage into comprehensible English. Well, not happily. The trick is to not read it. OK .. I'll do it on request. You can remain pretending to be happy with the copy of the Orwellian advertising doublespeak above until the request appears here.]

  • Haamid Bhat asked a question in Porphyrins:
    While geometry opimization, some parametres don't get converged.why?

    I have some porphyrin systems. i am optimizing their geometry, but they don't get converged completely. What may be the probable reasons

  • How is magnetic leakage reduced to a minimum in commerical transformers ?

    hi, How is magnetic leakage reduced to a minimum in commerical transformers ?

    Jean-Frederic Charpentier · Ecole Navale de Lanvéoc-Poulmic

    In 3-phase classical transformers, the primary and secondary windings are put one on the other in two concentric layers (in the same magnetic core column). It allows to minimize flux leakage between primary and secondary. 

  • Adam Piekarczyk added an answer in Bricks:
    How can I obtain the micro property of burnt clay bricks?

    I have one experimental study with only basic properties. But I need detailed nonlinear properties for DIANA micro modeling. So how can I obtain all these  parameters ? Plz help me. Is there any test result or theoretical formula for burnt clay brick properties  ? 

    Adam Piekarczyk · Silesian University of Technology

    I conducted research on masonry walls with solid ceramic bricks subjected to a vertical shear. What are the parameters you need exactly?

  • Younes Fathabadi asked a question in Optimal Control:
    Kirk optimal control problem is solved on someone?


    Kirk optimal control problem is solved on someone?

  • Raghda Abogabal added an answer in Light Microscopy:
    How can I see the microstrucure of pure tiny titanium specimen?

    For an titanium alloy I get microstructure using etchant of Kroll's Reagent.

    same i followed for Tiny pure titanium specimen of height 1mm and 0.5mm but i couldn't see anything?

    And also suggest me, Is there any other option for seeing micro structure for pure titanium other than polarised light microscopy? 

    please let me know if you have an answer.

    Raghda Abogabal · Mansoura University

    I had calculated microstructure calculations for Ti by Xray.

  • Where the use of ynd11 transformer?

    ynd11 transformer

    Jean-Frederic Charpentier · Ecole Navale de Lanvéoc-Poulmic

    For example in all electric ship  ship grid  yD and DD transformer are used in association to reduce hamonics related distrurbances due to high power converters in the grid.

  • Rustam Baitimerov added an answer in FLUENT:
    How can I compile or interpret UDF in FLUENT journal file for running in HPC?

    I have created UDF code I would like to intrepet in HPC.

    Rustam Baitimerov · Southern Ural State University

    For IBM Platform HPC you should run Fluent in Command Prompt, then compile your UDF.

  • Mohammad Ghoreishi asked a question in Determination:
    Wombat.par file

    who can tel me how i can determine the cavariate factors in wombat.par file?

  • Qijin Chi added an answer in Electrodes:
    What's the difference between the behaviour of Nickel as an anode and that of Pt as anode?


    Qijin Chi · Technical University of Denmark

    Hi Ketong,

    Your question is not clear enough. Do you use Pt or Ni electrode for normal electrochemical Measurements in liquid electrode, or do you use them in a solid-state battery or supercapacitor?  While Pt is a noble metal, Ni is a transition metal. They have very different atomic structure and physical properties. In normal EC meaurements, pepole rarely use Ni as a counter electrode (Pt has been most widely used). Ni is not stable in an acidic electrolyte, simply dissolved into Ni ions. However, Ni (particualy Ni foams) is good anode materials for supercapacitors in basic condition (e.g. 1 M KOH), forming hybrid Ni(OH)2/Ni surfaces.

  • Tarik Ömer Oğurtani added an answer in Creep:
    Whether the cavity formed and developed on materials were induced by strain or stress?

    from the view cavitation induced damage to the creep, does anyone have any suggestion about whether the cavity formation and development is induced by creep strain or the applied stress and what is the dominant mechanisms behind?

    I am really appreciated for your help!

    Tarik Ömer Oğurtani · Middle East Technical University

    Mostly micro cavity chains , which are nothing but growing vacancy clusters  are observed along those grain boundaries subjected to the applied uniaxial tensile stresses, and  aligned  almost normal to the direction of the stress axis. Theoretically one can't image to have creep strain without having applied stress unless one deals with the relaxation stage that takes place after one  turns off the applied stress.  With the acception of   high temperature Herring-Nabarro creep,  there is a large amount  of dislocation climb  occurs due to the vacancy flow to the compression sides of  the dislocations having edge or mixed characters.  This  temperature dependent  process especially enhanced very much under the applied high stresses, and the creep rate shows almost  sin- hyperbolic dependence  on the stress. (Barrett & Nix). 

  • Why is the power factor of a single-phase induction motor low?

      Why is the power factor of a single-phase induction motor low?

    Jean-Frederic Charpentier · Ecole Navale de Lanvéoc-Poulmic

    in induction machine (single or 3 phase) , a reactive power is needed to create rotor magnetomotive force. This recative power come of course from stator supply. It is why the power factor of such motor is low.

  • Younes Fathabadi asked a question in Google Scholar:
    Who knows how to search for articles in Google Scholar?

    Who knows how to search for articles in Google Scholar?

  • Is relative simultaneity a misinterpretation of Special Relativity?

    I really need a lot of feedback on this particular issue.

    I think that relative simultaneity is a computational effect of no consequences to real temporal relations. This is based on my analysis of simultaneous trajectories.

    My claim of apparent nature of relative simultaneity is based on the assertion that relative lengths of rigid objects or points moving at a constant relative distance to each other in a stationary system are not conserved (in general ) in the moving system after Lorentz transformation when expressing multiple points trajectories in terms of common time of the moving system.

    More details in the linked document and relevant draft article available from my RG profile

    Dear Eric,

    Our discussion has not been in vain. I was a bit disturbed, the fact is that I never use coordinates in affine space, or SR. So I checked carefully.

    1) the usual formulas hold for any change of bases in GR, so whatever the observers. But we speak then about bases defined in charts.

    2) In SR we can define consistently orthonormal frames if and only if the two observers are inertial (in uniform translation). So basically you are rigth about the Poincaré's group : the two frames are fixed (in time and space). And one needs 10 independant parameters to define the transition from one frame to another.

    However the Poincaré's group has been given a central role that it does not deserve : it does not seem wise to base a theory onto something which represents only uniform translations ! All the more so that the use of frames is not at all necessary.in Relativity. All the paradoxes that we can read on this post rely in one way or another on some misunderstanding of coordinates.

  • May gravito-electromagnetism be an alternative to Einstein's theory of general relativity?

    Gravito-electromagnetism (GEM) describes gravitation starting from the idea (suggested in 1893 by Oliver Heaviside and further developed by Olev Jefimenko) that there is a formal analogy between the gravitational and the electromagnetic phenomena.  This implies that - relative to an inertial reference system O - a gravitational field is characterized, in analogy with an electromagnetic field, by two vectorial quantities: the gravitational field Eg and the gravitational induction Bg.  The spatial mass destribution is the source of Eg  and the motion of the masses relative to O that of Bg

    According to GEM, a gravitational field is just like an electromagnetic field (Maxwell's equations) mathematically described by a set of four partial differential equations, the GEM-equations.   They describe how Eg  and Bg   vary in space due to their sources and how they are intertwined.  The action of a gravitational field on particles is described by a law analogous to Lorentz's force law: the force law of GEM.

    It has been shown that GEM can explain a number of phenomena (precession of planets and binary pulsars, gravity probe B experiment, ...) that are inexplicable in the context of Newton's description of gravitation what makes that GEM can be considered as a possible alternative to GRT.

    In line with the original idea of Heaviside GEM can be seen as an extension and a refinement of the "classical theory of the gravitational field", an extension that - besides the effect of the spatial distribution of the gravitating bodies - takes into account the effect of their motion.  GEM can theoretically be founded and explained by the theory of informatons. (https://www.researchgate.net/publication/268576021_GRAVITO-ELECTROMAGNETISM_EXPLAINED_BY_THE_THEORY_OF_INFORMATONS?ev=prf.pub)

    Let us still mention that GEM has been discussed within the context of general relativity by a number of authors and that it has been shown that  the GEM equations can be derived in the weak field approximation of Einstein's description of gravity.

    Dear Akira
    > lighting strikes these two points

    Not so important that two observers see in different reference systems, it's important what happens in the train system (K') in the framework of the theory of relativity. Here in K', if the train has completely filled the road then the point A coincides with point B, and then clock at those points of the train is unique, however this clock must show that the lightning had struck earlier and later! This is complete nonsense, and contradicts not only common sense but to reality also!
    This tells that it is impossible to synchronize clocks for rotating ring in GR. Therefore, there is no rotating frame of reference, and here no process is possible to be described in the framework of the theory of relativity.
    Уважаемый Akira,
    > молнии ударяют по этим двум точкам

    Не столь важно, что видят два наблюдателя из разных систем отсчета. Важно, что происходит в системе поезда в рамках теории относительности. А там, если поезд полностью заполнил дорогу, то точка А совпадает с точкой B, и тогда часы в этой точке поезда уникальные, однако эти часы должны показывать, что та молния ударила и раньше, и позже! Это вообще является полной бессмыслицей, и противоречит не только здравому смыслу, но и реальности!
    Это говорит о том, что нельзя синхронизировать часы для вращения на кольце в ОТО. Поэтому, не существует такой вращающейся системы отсчета, и никакой процесс нельзя здесь описать в рамках теории относительности.   

  • Liosber Medina asked a question in Visual Fortran:
    Linking Abaqus and Visual Studio and Fortran Compiler?


    I´m trying to make a Subroutine in Abaqus. I have doubts about linking version of the softwares. I have Abaqus 6.13, Visual studio 2010 and Intel Visual Fortran Compose XE 2011.5.221 But  I don´t why a elastic subroutine do not run. Any idea?


  • Can solvent attain higher temperature than its boiling point?

    I have seen in many publications that solvent is heated to higher temperature than its boiling. Is it correct?

    Ashawani Kumar Singh · University of Delhi

    100% incorrect

  • Vijay Jayaraman asked a question in Dispersion:
    Why do we use complex number notation to represent a signal in NMR? How do we physically understand or visualize the dispersion part of the signal?

    Basically when do we represent any function using complex numbers and why so?