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  • Manoj Gupta added an answer in PSAT:
    Can somebody provide a solution to my problem?

    i am using PSAT. My problem is when i  creat fault at any bus and  also varying load  , freq. is  increases ,this is not to be happen. i am not able to understand where i am doing mistake when i am using PSAT .there is problem in setting or other.I have tried to all versions of PSAT.I have also use 9 ,39 and 14 bus system.but same problem is happen in all system.please suggest me ?

    Manoj Gupta · IPS Academy

    i read whole manual  but didnt findout the reason.

  • Aamir Abbas added an answer in Face Detection:
    What is the best algorithm for face detection in Matlab?


    Aamir Abbas · National University of Science and Technology

    In Matlab use corr2(image1,image2) function where corr2 is correlaion between image1 and image2 and both images should be of same size. value of correlation is between -1 and 1 so if corr2 comes out above 0.8 than be images should be same.

  • Mj Kim asked a question in Fluid Dynamics:
    Is there any method to solve this nonlinear PDE using similarity?

    I stumbled upon equation j and l in my research.

    When I found some books related to fluid dynamics, it says solution to j is the formula k

    as you can see j and l looks similar. and similar boundary condition and mass balance.

    Assuming that solution to j is k, Is there any method to solve l and get the formula of h2?

  • Ahmed Boughdad added an answer in Mortality:
    Which correction for control mortality can I use when the sample sizes, N, are different?


    I just collected my last data on a mortality experiment involving different treatments.

    Each treatment as well as the control treatment had 20 individuals. The issue I have is that in one of my replicate, one individual is missing and which makes my N=19 instead of 20.

    I wanted to use the Abbott formula but as my N in my control is different than my N in this treatment, I am not sure it would be correct.

    Here is the actual correction I'd like to do.

    Control N=20

    Treatment N=20 or N=19 in one case

    Mortality in the control=1

    Thanks for your help

    Ahmed Boughdad · Ecole Nationale d'Agriculture de Meknès, Meknès, Maroc

    In your case, you have to use the HENDERS0N & TILTON's method.

    Kind regards.

  • Victor Christianto added an answer in Triplets:
    Is it possible to come up with a Classical model of Neutrino?

    In his recent paper, Valerii Temnenko proposes a new classical model of neutrino. He wrote the abstract as follows: "The theory contains a number of wave states, both one-sector (singlet or triplet waves) and compound two-sector ones (singlet-triplet waves). Wave states differ in number of currents: zero-current waves (free singlet or free triplet waves), one current, two-current, three-current and four-current ones. Wave states also differ in character of four-dimensional wave vector (the waves with time-like and space-like wave vector). Some forms of waves may have negative density of energy. Some wave states can be treated as classical models of a neutrino. Neutrino states are classified in accordance with the character of the current which forms the state: singlet (maxwellian) neutrino, Yang-Mills triplet neutrino, Maxwell-Yang-Mills singlet-triplet neutrino."

    Do you think that such a Classical model of Neutrino is possible? What is your opinion? Thanks

    Victor Christianto · University of New Mexico

    Dear Andrew, Faical, Oliver and Akira: thank you for all your comments. I know Temnenko's paper may not be so convincing, but this is the only one i know which tries to describe classical model of neutrino. If you know any other paper, please kindly let me know. Thanks

  • Dmitry Zinovkin added an answer in Gelatin:
    Experience on gelatin coating of glass slides for autoradiology/histology?

    Does anyone use chromalum as a mordant, when coating microscopical/autoradiography slides with gelatin?

    I only need answers on experience on the difference:


    With or without chromalum/mordant.

    Dmitry Zinovkin · Republican Research Center for Radiation Medicine and Human Ecology

    We use for mordant thymol (3-4 crystals at 100ml of the filtrated gelatin solution)  You will have bacterial contamination without mordant. It will give problems with adhesion of sections on slides a artifacts after staining

  • Sapdo Utomo added an answer in LMS:
    What is the LMS algorithm derivatives?

    What is the LMS algorithm derivative

    Sapdo Utomo · Indonesian Institute of Sciences

    It's one of Adaftive Filtering Technique. For more information You can read this articles. I hope that can help you to understand fundamental of LMS algorithm.


  • What are the differences between Roman and Greek fathers in their power over their children?

    Classics (Latin and Greek), Ancient History, Historical Social Anthropology

    I am interested in comparisons of the power [especially of life and death] of the Roman Father over Children to that of the Ancient Greek Father. What are the differences?  What is the best secondary literature that deals with the subject?

    Clifford Angell Bates · University of Warsaw

    The problem with deducing ancient Greek practices from modern ones is the long influence of Ottoman control and the influence of Islamic practices that were violently imposed by their Ottoman conquerors. 

  • Can anybody give me detailed step by step analysis on how to carry out moisture absorption test on polymer composite?

    Water absorption

    Sangram Keshari Samal · Ghent University

    All samples should have same dimension and weight, you can perform your experiment in moisture chamber.

  • Marc Tessera added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.


    "You used to  insist on rigourous scientific method and here you have an opportunity to clarify what is the bottom line of a science of consciousness. Is the definition of the relation of 3th person observables a good one or not?"

    I am not sure to understand what you mean by "3th person observables".

    What I can say is that all the scientific studies on consciousness are based on person's self-report, as I have always specified it.

  • What is the purpose of adding salts in a RNA/DNA extraction buffer?

    Hi all.

    I recently isolated DNA and RNA from a home made extraction buffer. In one test, I added sodium acetate during precipitation, and in the other, I added it directly while making the extraction buffer, and nothing during precipitation. Curiously, the test without the sodium acetate during precipitation yields consistently good results.

    Can anyone please explain as to why this is? Thanks.

    Mirshd Puthanveettil · MES Academy of medical science

    i think it is for precipitating the proteins in the given sample

  • Debabrata Podder asked a question in Elastic Modulus:
    Lesser Tangent modulus values of low carbon steel is giving less deformation: Why ???

    I am conducting some welding experiment on low carbon steels. The bilinear isotropic hardening is considered in our elasto-plastic model. I have conducted the welding analysis considering different values of Tangent modulus (other parameters are remaining same). The Tangent modulus considered are: 16% of E, 1% of E, 0.2% of E and 0.1% of E, where E = Elastic modulus of steel. The lowest deformation is coming for 0.1% of E of the Tangent modulus. And this one is nearly matching with the experimental value. Why it is so? What are the guide lines for choosing the tangent modulus? Kindly help. Thanks in advance. 

  • What is the positive and negative sides of perovskite solar cells?

    Most probably the best thing of a perovskite solar cell is their easiness to fabricate and low cost. But I am more interested about the drawbacks of perovskite solar cells. 

    Your kind comments on this will be very much appreciated. Thanks in advance 

    Beatriz Romero · King Juan Carlos University

    The main problem of perovskites is the lack of stability. The efficiency is high, compared to OSC, but decreases very fast.

  • How can we use scatterplots to solve a problem in data analysis?

    Specific examples are of interest, as well as general approaches.

    As examples re data editing for continuous data for establishment surveys, the first link below leads to some slides for a seminar presentation, which are illustrative. It was found on several occasions over a number of years, that data analysts accustomed to pouring over data tables, became very enthused by the clarity that selected scatterplots gave them in seeing relationships between data sets.

    The second link is to a procedure and spreadsheet for graphing confidence intervals about predicted y-values when points from a scatterplot are considered, using the model-based classical ratio estimator.

    Your comments, other uses, and in particular, links to other specific instances of uses or general uses of scatterplots for problem solving of any kind are solicited.

    Data editing and analyses are illustrated through the attached links, but model selection and statistical analyses in general would also be among potential uses. Others on ResearchGate have noted that for selection of regressors, theory must be considered to avoid use of spurious associations, and this must be considered, but scatterplots may help to explore possibilities. Further, scatterplots may be used to explore whether or not a relationship may be considered linear.

    Any examples you can show are welcomed. Anecdotes may be instructive and entertaining.  - Thank you. 

    Christopher R. Lee · Retired

    Essentially accidental relationships are not spurious when gene linkage is involved. Jim's unfortunate situation could be an example.

    One that comes to mind, writing from memory, relates to tomato breeding. A gene that causes the fruit to ripen progressively from one end of a truss to the other was bred out. This conferred an obvious economic and commercial advantage though it would be a disadvantage in the wild and for those who grow their own.

    The big disadvantage was that the new tomatoes had no taste; this was because a gene for the relevant tasty metabolite just happens to be on the same chromosome and close to the one for progressive ripening. The odds on a crossover occurring between two genes (thus separating them) decrease the closer they are together. Conversely, the chances of two loci recombining are greater the farther they are apart.

  • Rajeev K Singla added an answer in Dosing:
    From Pharmacological Point of view, which one is important - Dose Dependent Activity or Dose Independent Activity?

    I would like to know what is more important when we talk about drug discovery /pharmacology. Dose dependent response curve or dose independent response curve. And which one in any specific case

    Rajeev K Singla · Netaji Subhas Institute of Technology

    Dear Dr. Venkatesham, Can you please throw more light on these aspects.

  • How Organization of the Islamic Conference (OIC) using Islam to Islamize the world?
    The question needs to explore various methods specifically used by OIC to islamize the world. Some considers the organization being political, others religious and others socio-economic. If it is religious based, how?
    Emmanuel Buganga · Trans-Africa swahili Christian Ministries

    Dear Omar,

    Thanks indeed for your contribution.

  • Zahid Aziz added an answer in Seaweed:
    Is there any antimicrobial activity of seaweed against dental microbes?

    I would like to know whether seaweed is having antimicrobial activity against dental microbes or for any pathogens. 

    Zahid Aziz · Misan University

    Dear colleague

    i  hope that u will benefit from pdf attach which highlighted on  your subject with my respects 

  • K. Gowri Shankar added an answer in Rat Models:
    How can I dissolve methonolic extract in deionised water for in vivo analysis using hepatocarcinoma in vivo SD rat model?

    i am planning to dissolve methonolic extract in deionised water but in articles people have mentioned to dissolve their extracts in carboxy methyl cellulose 2%, DMSO 2% and PEG 2%. but i tried to dissolve my extract in deionised water and its taking time to dissovle completely but its dissolving.so can i use deionised water for hepatocarcinoma invivo SD rat model?? and for invivo SD rats how much mL of deionised dissolved extract can i give orally??

    K. Gowri Shankar · Loyola College

    Dear Md Moniruzzaman ,

                                 Thank you for your reply..my main concern is not ordinary water its deionised(without any ions in it and pH is arround 7-7.3 same pH as i used for my invitro study to dissolve extracts in PBS buffer). is it possible to use deionised water. maximum ill go upto 2-3mL..rite now rats are arround 320-360g.

  • Can rotation in Minkowski space-time be the product of two rotations about two lightlike planes?

    It is known that rotation in Minkowski space-time is product of two rotations about spacelike and timelike mutually orthogonal planes. Can we represent  rotation in Minkowski space-time as a product of two rotations about two lightlike planes?

    Jost Eschenburg · Universität Augsburg

    Dear Emilija;

    Many thanks four explaining your question. I think that the answer is yes at least for the boosts: They can be obtained as a composition of two rotations about lightlike planes.

    I guess that these rotations are precisely those elements of the Lorentzian group which fix precisely one lightlike direction R.n (the direction of the lightlike fixed vector n). In other words, for such Lorentzian transformation A, there is no second likelike vector n' (which is not a multiple of n) such that  An' = tn'  for some real number t.

    (Proof: Otherwise, the timelike plane (n,n') would be preserved, hence fixed (since n is fixed), thus A is a rotation in the spacelike plane perpendicular to (n,n'), but this must be trivial since A has also a spacelike fixed vector.)

    Now we pass to another model of the Lorentzian group: It acts on the 2-dimensional sphere S^2 as the group of conformal (Moebius) transformation; the sphere is the boundary of the light cone modulo scalar multiples. Conformal transformations with just one fixed point are precisely planar translations when S°2 is identified with the plane R^2 via stereographic projection whose center (north pole) is the fixed point of the given conformal map. I would rather view this conformal map as a vector field on S^2 by transplanting the translation vector to S^2 by the stereographic projection; the given conformal map belongs to the flow of this vector field.

    Now consider two such vector fields v,w, where v has its zero in the south pole and w in the north pole. It is enough to consider the great circle S^1 \subset S^2 through the north pole and south poles in the direction of the translation vector in the plane. Then we see that the conformal vector field v+w has two zeros (in the "east" and "west" poles on S^1, so to speak). Hence v+w correspond to a conformal map (the flow of v+w) with two fixed points, and this corresponds to a boost in Minkowski space. Vice versa, any boost has two fixed points which can be (after conformal transformation) considered as north and south pole of the 2-sphere and the above construction applies.

    Clear enough?

    Best regards


  • Raheleh Tooyserkani asked a question in Transfection:
    Detecting secretary GFP-fused proteins in DMEM supernatant?

    I've transfected HEK293-T cells with plasmid expressing for a secretary GFP-fused protein. I would like to know is there any method rather than ELISA test to detect my protein in supernatant using GFP?

    Best Regards

  • Edmond Maican added an answer in Ethanol Production:
    Is anyone working on low cost medium or pretreatment techniques for bioethanol production?

    Want to get information about how to reduce ethanol production costs?

    Edmond Maican · "Politehnica" University of Bucharest

    Pretreatment and distillation are some of the most energy-intensive processes. If you are looking for technologies with market potential, then some good solutions would be:

    1) SPORL pretreatment (up to 80% energy economy for biomass size reduction; can be used with existing equipment and procedures used in pulp and paper industry, including waste water treatment and subsequent chemicals separation);

    2) Continuous extrusion pretreatment (simple technology, continuous preocess, can be applied with or without acidic/basic catalysts; good results without catalysts; possible to work at moderate temperature (less than 100 degees celsius), high mechanical energy but no need for subsequent steps like waste water treatment or chemicals separation when used without catalysts, negligible percent of fermentation inhibitors);

    3) Pass-through fermentation - see Drystill canadian company (ready for market roll-out, 50% less energy consumption than classic distillation; distillation at room temperature, which means that it is possible to recover and reuse yeasts and/or enzymes)

    Hope these will help.

  • Can anyone help me about the total of the macroalgae in the Mediterranean Sea?

    Are there any information or recent studies ( ≥ 2013) concerning the total estimates of Mediterranean species of macroalgae ?

    Mustapha Hassoun · Abdelmalek Essaâdi University

    Dear José,

    Thank you very much for your suggestion.

  • Zahid Aziz added an answer in Plasmid Extraction:
    Can anyone help with plasmid extraction of staphylococcus aureus using Qiagen kit fail?

    Hello everybody...i just want to ask...i did plasmid extraction of staphylococcus aureus by using qiagen kit but fail to get any band after i run gel. Before i used kit, i incubate bacteria pellet in 50mg/ml lysozyme. I'm not used lysostaphin because of very costly since i deal with huge sample..any suggestion from the floor?...thank you

    Zahid Aziz · Misan University

    I AM agree with that of my colleague J. HARRY in idea that the cell wall of gram positive bacteria is very strong because the peptidoglycan layers but the use of lysozyme will solve this problem which can prepared as follow 0.1 of lysozyme ,  50 ul Triton X-100,  0.012 g of  Tris base  and 0.004 g of EDTA and adjusted to ph = 8 

  • Martina Gaisch added an answer in Collaboration:
    What are the maın barrıers ın embarkıng on shared research?

    challenges and ımpedıments ın collaboration while  carrying out researches wıth colleagues. What actually incentivizes some researchers to refrain from   any group  research study.

    Martina Gaisch · Fachhochschule Oberösterreich

    Dear Ali, 

    This is great question and I could not agree more to my previous writer. Yet, I believe, there are also further elements that come into play, especially when it comes to cross-border collaboration. 

    • What do we expect from each other?
    • Who takes the lead and how independently should the work be done?
    • How to allocate the tasks and how explicitly should this be communicated?
    • How about tacit assumptions, codes of significations?

    Low-context and high context cultures have completely different communication patterns that also effect their working style and expectations when engaging in joint research. 

  • Victor Christianto asked a question in Lectures:
    Is it possible to come up with a classical model of QCD based on SU(3) Yang-Mills theories?

    It is known that QCD is based on SU(3) Yang-Mills theory. This reminds me to a lecture around 2009 , the lecture was given by Prof. Yu P. Rybakov, and it was about Yang-Mills theory. Actually i did not follow all the arguments, because it was in Russian, and i cannot speak that language. But during the lecture, an idea came to me: if Yang-Mills equation is known as classical, and QCD is based on Yang-Mills theory, then does it seems logical to find out whether it is possible to derive a classical model of QCD based on SU(3) Yang-Mills theory. Then i asked 

  • Vineet Jain asked a question in Shopping:
    How can use genetic algorithm in Job shop scheduling?

    How can use genetic algorithm in Job shop scheduling?

    Regarding implementation of the algorithm and code etc. in scheduling problem?

  • What are the software available to study phylogeny in plants and to stressed out mutation rate (insertion, deletion) ?

    Phylogenetic study of plants need to develop a tree using MP ML NJ however i would like to know about a software that will detect a mutation on order of nucleotide of ITS and rbcL sequences from plants sample

    Mahmoud Magdy Elmosallamy · Ain Shams University

    Hi Bipin,

    Try MEGA V6 it will help you with the alignment and phylogenetic analysis. Mutation or changes in nucleotides can be detected visually using viewer options in the program or can be determined using any SNP/polymorphism detection programs (I recommend Geneious, it is very user friendly- even it is not free but you can request a 15 days trial).

    On the other hand, ITS spacer is not a coding region like rbcL, so for the rbcL, any program with an option to translate the coding sequence would detect Amino Acid changes due to the mutations (Both Mega and Geneious can help you with that). While significant mutations in the ITS2 region would be revealed by forming secondary structure analysis (Use the online web-tool http://its2.bioapps.biozentrum.uni-wuerzburg.de/ ) that would reveal significance mutations related to the ITS2 function that is present in your alignment.

    Both programs and web/tool are very easy to apply, and all will start from sequence alignment to a tree. 

    I hope that would help, 


  • Andrea Serra added an answer in GC-FID:
    What type of GC column is better for GC analysis of non-derivatized free fatty acids?

    We are interested in GC-FID quantitative analysis of FFA without previous derivatization, and I would like to know what column type and model is better for this purpose. Our objective at first is the study of FFA in dairy products.

    Andrea Serra · Università di Pisa

    Agree with Abdur. Diazomethane is very hazardous due to very difficult "generation". For this reason I use a product from Sigma: trimethylsilyl-diazomethane 2.0M hexane solution (cod. product 362832); You can find the procedure in Serra et al. (Meat Science 97 (2014) 504–512). Regarding to the internal standard in my opinion is better to use a free fatty acid; you must be careful to volatile fatty acids, so I suggest to use more than one internal standard: one for the determination of volatile fatty acid (C5:0 or C9:0; if you use the C9:0 you must calculate the correction factors due to the fact that C9:0 is not so volatile as C:4 and C:6). For the determination of the no-volatiles fatty acid you could use C19:0.

    greetings. Andrea

  • Gianrocco Tucci asked a question in Reality:
    Is Knowing an automatic act of apperception that somehow involves freedom and self-consciousness of a subject?

    The need to find a unifying principle for all knowledge, an original synthesis meant as an ‘a priori’ representation of all a man knows and as such precedes the consciousness itself of multiplicity, leads Kant to elaborate the doctrine of '' I think ', which is one of the most debated and significant point of his whole philosophy.

    The different representations of my intellect are unified in the horizon of what I thought, because they are accompanied by the awareness that I think about them. The ‘ I think’ is therefore the supreme principle of all synthesis, i.e. the horizon which the synthesis made by the categories connect in a unified manner, and as well the principle of every knowledge whereby the mind is conscious of the created unification. The principle makes it possible a real unitary knowledge of reality and at the same time it takes root in the awareness of the constitutive human finitude: it is worth noting that, in this sense, the ‘ I think’ is an organizing principle, a transcendental structure that "must accompany" the representations of the subject, and not the principle from which the whole reality depends, as it will be understood later by idealist thinkers .

    Fichte, for example, in a letter of 1793, would say of  Kant, "this unique thinker becomes to me increasingly marvelous: I think he has a genius that shows him the truth, but without revealing the fundamentals." However, on his part, Kant is much careful to point out how the ‘I think’ is the structure of thinking of each empirical subject, and then as it does not coincide nor - in the wake of Descartes - with an ‘individual I’ object of immediate self-consciousness, nor - as suggested by Spinoza and taken by idealists - with the ‘absolute I’ that is the foundation of all finite consciousness.

    Specifically, the problem that Kant sought to resolve, which he addressed in the transcendental deduction of the Critique of Pure Reason, was as follows: why nature seems to follow necessary laws by conforming to those of our intellect? By what right do the latter can say to know scientifically the nature, "establishing" the laws in one way rather than another?

    According to Kant, such a right is justified because the foundation of our knowledge is not in the nature but in the activity itself of the subject.