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  • Georgy Sergeevich Kalenkov asked a question in FFT:
    Integral calculation optimization based on FFT application

    Is there any conventional approach to calculate the following integral:

    (x,y) = int [ A (u,v) * (x,y,u,v) * exp [ i (x*u + y*v) ] dudv

    The part A(u,v)*exp[ i (x*u + y*v)] represents a conventional FFT. But I also have a set of functions H(x,y) which have their own distributions in u,v - plane. One direct way is to perform N calculations substituting Hfunction one by another. The question is if there is a way for optimizing the calculus by reducing the number of calls with some general FFT approach?

  • Garima Bhardwaj asked a question in CMC:
    Critical Micelle Concentration (CMC)

    How to calculate Critical Micelle concentration (CMC)?

  • Is there a place for social media in Education?

    Many persons have been touting the use of social media in education?  Should more schools explore this?   At what level of education will this work best?

    Dali Osepashvili · Ivane Javakhishvili Tbilisi State University

    Dear Mardene Rosalee, If you interested in my experience in this topic, I can suggest you my paper: 

    "The Using of Social Media Platform in Modern Journalism Education"

    D Osepashvili

    DOI: 10.13140/2.1.3337.0245 Conference: European Conference on Social Media: ECSM 2014, At Brighton, UK. pp.378-387

  • Harish Kumar Kotapally asked a question in Wavelets:
    Can anyone tell me why f(t) has to be defined over [0,1) in Legendre wavelet ? (Can't we include "1" also)?

    I am unable to understand why people are taking [0,1) in Legendre Wavelet?. What is the problem if they include one also ? {like [0,1] }. In Haar wavelet if we include 1 we cannot prove the Orthogonality of the basis. Here I am able to prove the Orthogonality of Legendre wavelets even if I include the one ! Please go through the following papers for details. Thanks in advance.

  • Miranda Yeoh added an answer in Support of Research:
    Do you support the establishment of industrial plants by a university?

    A university, with a student population of e.g. more than 25,000 & with academic, administrative, and services staff of e.g. more than 2000, consumes lot of papers (despite the existence of electronic displays & versions) and lot of liquid detergents for its laboratories, cafeterias and water closets. If such a university has qualified staff, it can start two medium-scale batch chemical industries to produce what the university needs of these 2 items (papers & liquid detergents).These 2 industries can be made environmentally-friendly.

    Advantages of these 2 industries are enormous. To start with, the university will save money & will train students industrially on the campus.

    Some industries have gained huge profits from universities, but when it comes to supporting  research in academia or accepting students for training in their practical service courses, these industries show negative attitudes. Isn’t it time for the universities to stand up & industrialize part of their activities?

    Miranda Yeoh · Kolej Matrikulasi Selangor, MALAYSIA (Selangor Matriculation College)

    Dear Dr Nizar, since world class universities and industry have been collaborating for over a century, and these strategic partnerships has gone beyond the traditional funding of discrete research projects, I am quite open to your idea, to industrialize some of the varsity activities.  I studied in an agricultural university that collaborated with many agribusinesses, and it has profited us all.  But the partnership must not be stopped, it must be made to work.

  • Why am I getting very low yield when I try to prepare lavandulyl acetate by exactly following the same method as written in this paper?

    I am getting very low yield as about 3.5% Lavandulyl acetate only. How can I increase yield upto 26.5% as written in your paper. Is there anyway? I exactly followed your protocol. 

    Iuliana Vasian (born Budae) · Babeş-Bolyai University

    If I find another information I will send you. Firs try prenyl acetate at starting material.

    I thank you.

  • Why to use polyherbal combination of medicinal plants for the treatment of any disease?

    Polyherbal combinations in Ayurveda.

    Saeid Davazdahemami · Research Institute of Forests and Rangelands

    we believe each pure drugs has side effects. in medicinal plants we have lots of components which reduce side effects and sometimes we have to add other materials such as minerals or plants to complete the main effect. Besides some times some synthetic material such as some essence aren't similar to natural kinds exactly, they are isomers (e.g.  L and D isomers). in our bodies they act differently.

  • Does anybody have experience with heavy metal determination by AAS?

    Dear all,

    I've collected the tannery effluent and treated it with my purified enzyme. When I checked the heavy metals in atomic absorption spectroscopy, the concentration of copper in tannery effluent was 1.05 mg/L and, when treated with my enzyme, the concentration should be decreased down to 0.34.

    What does this mean? Is the enzyme (protein) capable of adsorption?

    Taratisio Ndwiga · Moi University

    There are some enzyme which absorbs the heavy metals in water. please check the literature and you will see this.

  • Eddie Seva See asked a question in Dissertations:
    When you sit as evalutor in a thesis/dissertation defense, what question/s do you usually ask?

    I wonder if there are "common" questions asked by evaluators.

  • Nicholas E Rowe added an answer in Ayurveda research:
    What is the ultimate aim of publication in high impact factor journals ?
    During last 6 - 7 years publication of good Ayurveda research in high impact factor journals has become aim of researchers. How does this help in serving the society ? How can the knowledge of Ayurveda revived through new researches be used in patients especially in rural areas where the clinicians cannot access these journals / researches. Is Global acceptance of Ayurveda the last goal ?
    Nicholas E Rowe · University of Lapland


    Very good article that talks about the differences of impact factor between specialities, which shows that the impact metric is a very skewed measure.  It also de-bunks the myth that those who 'pay to publish' are producing inferior work.   -   Take time to read it  :-)

  • Is it time we forget climate change & focus on the 'Human Dimension'? Is it not obvious that nature can heal itself, if only left alone?

    A lot of hue and cry is made about climate change and the environment in general. Public and private money is poured into research to study its effects on the environment, sustainability etc. Should we study nature or ourselves?
    Human activities have been found to have a direct correlation to climate change and its impact on the environment(I=P x A x T, the Ehrlich and Holdren equation), in spite of what some complacent sections say to protect their own self interests. It is pretty obvious that it is human beings who need to be studied. We hardly know about Human nature. We can scarcely predict human behavior. We need to find out why we think like we do and why we do what we do and why, in spite of all knowledge and wisdom, consume more than what we need, in the form of addictions to consumption and imbalance not only ourselves but also the family, society and environment around us..
    Humanity is directly responsible for all the unnatural imbalances occurring on the planet. Yet we refuse to take responsibility and instead focus on climate change, or fool the public exchequer with a 'breakthrough in renewable energy just around the corner'. We scarcely know what drives human beings. If we had known, all the imbalances around us would have had solutions. Are we blindly groping in the dark of climate change because we don't know the answers to our own nature?
    Is it not high time we focus on what makes us human, correct our consumptive behavior and leave nature to take care of climate change? Why focus effort on 'externals' when the problem is 'internal'- 'me'?
    Aren't we addicts denying our addiction and blaming everything else but ourselves?

    " We are what we Think.

    All that we are arises with our thoughts.

    With our thoughts, we make the world." - Buddha 

    IMHO, We don't need to save the World. It is enough if we save ourselves from ourselves. The need of the hour is not vain glorious interventions, but self-restraint and self-correction!

    Raveendra Nath Yasarapu · Technische Universität München

    Dear All,

    Broadly, these are the theings we need to make clear

    1. What is responsible for Climate change?Nature itself OR Human activity?

    2. If human activity is responsible, how do we deal with the problem? TECHNOLOGY:-With more Technology again(which incidentally caused the problem)  OR HUMAN DIMENSION:-through Conscious & Mindful self-restraining activity and minimizing individual consumption following natural laws.

    3. As many might be uncertain and side with either TECHNOLOGY or HUMAN dimension, what is the definitive proof that Technology is the solution or is it the Human Dimension?

    4. IF Human Dimension IS the solution, as technology has only acerbated the situation, far from improving it, what is the Human Dimension? What is the nature of Human nature? How do we apply it upon ourselves, transform ourselves and serve as a role model for others to follow suit?


  • Vijayan Sokkappan asked a question in EDC:
    Deprotection of nitrone (o-triazole linkage)

    while doing amide coupling from acid(this moiety also have alcohol gp) with amine by using HOBt with EDC ,i have got by product as O-triazole compound as 50%.Can anyone tell to how to deprotect the triazole.I already tried Zn/AcOH,Zn/HCl,Zn/amm formate but not getting 100% deprotection of acohol

  • Eva Oktarina asked a question in Eugenol:
    S it possible to isomerize eugenol to iso-eugenol with enzyme (isomerase class 5.3) ?

    Is it possible to isomerize eugenol to iso-eugenol with enzyme (isomerase class 5.3) ? 

  • Swathi Sasikumar asked a question in Particle Physics:
    What is the role of a vector meson rho in marking a Gamma gamma event in a particle physics?

    Hi all,

    I wanted a detailed explanation of why Rho meson is so very important in marking a Gamma gamma event.Or it would be great if someone could suggest me some papers related to this topic.

  • Does Ackermann function belong to Mu-recursive function?

    Some books say that a function can be Turing-computed if and only if it is a Mu-recursive function [1] . So Ackermann function should be Mu-recursive,Here,Mu-recursive is defined by primary recursive functions by composition or recursion schemes.

    Meanwhile, it is proved that Ackermann function is not primary recursive function, so it should not be Mu-recursive, which is contradictive to the above proposition.

    Then, does Ackermann function belong to Mu-recursive function after all?


    [1]Thomas A Sudkamp.Languages and Machine:An Introduction to the Theory of Computer Science,Third Edition, Pearson Education, Inc.,2006,pp.415-416.

    Peter T Breuer · Birmingham City University

    I meant exactly what I said - nothing else.

    This is just the ordinary 'denotational' semantics of programming, as expressed by Dana Scott et al about 40 years ago. Every program that you write has the semantics of the least fixed point in a certain computational domain (that is, a distributive lattice with limits of ascending chains) of a certain operator. The Ackermann function is no different from any other program in that respect.

    I wrote out the operator in question in my expression. It is the map A->A', where A'(0,n+1)=A(0,n)+1 and A'(m+1,0)=A(m,1) and A'(m+1,n+1)=A(m,A(m+1,n)). A fixpoint of that in the lattice of partial functions NxN->N is the semantics of the Ackermann function program as usually defined by your equations in a programming language. That it coincides with the mathematical function in value depends on the semantics of the programming language giving rise to a total function as the fixpoint. A stupid semantics might go into an infinite loop instead.

    The stuff on mu-recursion is from an earlier epoch, about thirty years before that, when they didn't have any experience with computers, or any computers, so they tried to reduce program semantics to arithmetic, which they were familiar with.

    They only considered the (strict) domains N, NxN, ..., effectively. All their programs have no subroutines and consist of one big set of nested loops "for (m=0;;m++) { for (n=0;;n++) { ... }}" with simple stuff inside.

    My question, which you continue not to answer, was wether you allow me to break out of the for loops when I find a solution, and point you to the value of the m counter only, or whether you insist on me coding the loop counters m,n,...  up incomprehensibly so that there is only one outer loop with one counter k, maybe coding k=2m3n... so that when I break out of the loop with the solution I have to do some more work to extract m from k.

    I mean, nobody cares about such trivia. But you seem to!

    The code for (m=0;;m++) { if P(m) then break; } is what they wrote as mu m: P(m). The value of m at the break is what is returned. This is a kind of subroutine. The m is local to the subroutine, but it gets exposed when the routine returns, so one has to be careful.

    Kleene's theorem says that one can get rid of "subroutines" like this, in favour of just having one main() routine.

    But nobody uses such weird programming constructs any longer .. well, except hardware specification languages. That loop, with some extra stateful computation, is the only subroutine kind in VHDL, for example.

  • How to identify decomposition algorithm?

    How to implement a lagrangian decomposition algorithm to a dynamic model?

    for example a have a paper which is "A Lagrangian Algorithm for Optimal Emergency Voltage Control"

  • Jeevithan Elango added an answer in Electrospinning:
    Which physicochemical properties can be taken into account for the collagen extracted from chicken feet to make nanofibres through electrospinning?

    collagen properties

    Jeevithan Elango · Shanghai Ocean University

    Hi Damodar,

    The important properties are amino acid composition (especially imino acids, HYP, Pro), Td, solubility and structure.

  • John Sowa added an answer in Linguistics:
    Is human thought a form of internal speech or is it independent of language?
    Can it be that, by necessity, all psychological faculties are innate and learned, biologically restricted and socially constructed at the same time? At the end, the human body is (innately) pre-structured to interact with the world external to it. Is it possible, therefore, that most discussions about Sapir-Whorf hypothesis are just a case of simple misunderstanding?
    John Sowa · VivoMind Resarch, LLC


    After all this debating, I'm happy to let you have the last word:

    "I think our disagreement comes from my emphasis of commonalities and your concentration on differences. But even this is misleading as I am convinced that you and I accept the importance of both aspects equally."

  • Sulav Shrestha added an answer in Dairy:
    What can be the highest milk fat level in dairy cows in post-milking samples?

    What can be the maximum level of milk fat in dairy cows if the milk samples are taken post-milking by hand stripping? I am getting up to 20%! I understand that the milk fat level tends to increase as the milking proceeds. But the value i am getting is terribly high. Is this possible? Taking milk samples through herd testing process using meters, where the milk samples can be equivalently drawn out of each quarter, is not feasible in my trial. However, i try to strip out milk equivalently from each quarter. Can anyone give me any feedback regarding the results i am getting?

    Sulav Shrestha · Massey University

    Toby, did u mean the lighter lipids accumulated at the top of cistern in the initial milking and in the later stripping, they were concentrated?

    Grzegorz: All the cows are on pasture; Mostly HF, few Jerseys, in early month of lactation, none are heifers. There aren't much variation except for age, and difference in milk fat were seen within Jerseys and HF too.

  • Debashis Mandal added an answer in Pedogenesis:
    Is there any method based on soil genesis to determine permissible erosion limit or soil loss tolerance limit?

    Presently permissible erosion limit is computed based on soil depth and soil properties for conservation planning. This method should be tested or verified by using soil formation rate or soil regeneration data at a given site of place.

    Debashis Mandal · Central Soil and Water Conservation Research and Training Institute

    Thank you for your reply. I will appreciate you if you kindly share this two publication with me. I am really interested to know how the soil production rate can be measured. Recently I have come across some paper on soil production rate published in Science (Journal). I look forward to get a copy of your study.

  • Vijayan Sokkappan added an answer in Antibacterials:
    Is bacterial cell wall (g+ve * g -ve) hydrophobic or hydrophilic?
    Bacterial cell wall
    Vijayan Sokkappan · Apotex Pharmachem Inc.

    I thing this is useful for u.check it following link


  • D.P.S. RATHORE added an answer in Papers:
    Should we question the credibility of international conferences?

    We see most of international conferences accept more than 90 percent of the papers that they receive regardless of the quality of the papers or plagiarism possibilities. Shall it make us think that the conferences are only business?

    D.P.S. RATHORE · Atomic Minerals Directorate for Exploration and Research

    I fully agree with Singh Shivakumar views and beyond doubt, it is the moral responsibility of Seniors  /experts/ reviewers/ organizers/ Editors/conveners/ publishers/ to ignite the mind of the young scientists for a meaningful future research applications/research.  

    Unfortunately, the cases of scientific misconduct are increasing day by day due to greediness of the individuals for quick gain, fame, etc.   There was a Seminar cum Workshop on Modern Methods of Chemical analysis -Future Trends (MMCA-13) November 20-22, 2013 organized by CSIR-National Metallurgical Laboratory, Jamshedpur & Atomic Minerals Directorate, Hyderabad. Proceedings of this seminar were published in a special issue of Journal of Indian Chemical Society. Truely speaking, the actual review process of publications starts after its publication.  I have also raised comments  related with  five publications by Senior Scientists  in vol., 90 of J. Indian Chemical Society, November,2013 and addressed to the Editor.  It was extremely shocking and painful  to get a reply from the Editor. The reply of the concerned Editor is unscientific and I would like to quote here, quote:

    Dear Dr. D. P. S. Rathore,
    We have reviewed your criticism and contacted Authors. Whole things are discussed in an Editorial Board and with Indian Chemical Society Administration. It is opined that Issue is dedicated to 50 years of NML, Jamshedpur India; articles had been invited and reviewed by a Reviewers Board constituted by ICS and NML. Board had decided the publishing quality of the manuscript.  So, Journal of Indian Chemical Society does not entertain any criticism on this matter and hence the matter is closed.
    Thank you for your effort.
    Sincerely yours

    C. Sinha
    Editor, Inorganic & Analytical Chemistry Section, JICS

    In my opinion, this is not the scientific basis to decline my query and I (strongly) disagree with the decision of The Editor.

    I have further requested to the Editor to kindly review his decision and publish my query. I have decided to continue my efforts in this direction.

    Any query and the author’s reply should be published as per the standard practice adopted by the Editors of international Scientific journals/publishers. If any author fails to respond or do not respond , such authors should be blacklisted and query should be published without delay with a note from the Editor.

    Recently, I have tried my best through various  ‘Letter to the Editor’ publications  in this direction. It is the most challenging task of Institution involved, Reviewers, Editors, Publishers, Readers, and finally of the Experts to discourage practices of organizing such manuscripts and need to change the mind set of such persons for real scientific contributions in future research.

    In my opinion, the mindset and activities of such the so-called researchers holding senior positions are highly dangerous and destructive for the growth of any organization/ or nation in fulfilling the mission and mandate, if immediate steps are not initiated..

    This is for the prompt action and meaningful suggestions by the valuable readers.

  • Ardalan Armin added an answer in Graphene:
    What should be the minimum thickness of a graphene film that can be used to replace ITO for different application purposes?

    Minimum thickness of Graphene film to replace ITO.

    Ardalan Armin · University of Queensland

    To replace the ITO with another TCE is a challenge.  Broadly speaking, the sheet resistance and transmission are important. ITO does not have a fantastic sheet resistance (10-15 Ohms/square) in films with typical thickness of 100 nm which give transmission of ~90%. Multi layer graphene has been used to replace the ITO in solar cells ( not so sure whether you can still call it graphene then!) but they cannot deliver same performance. Single sheet graphene is indeed not rigid enough to be usable in optoelectronic devices easily. One of the msot successful examples is this paper: DOI: 10.1021/nl501981f

  • Zabed Hossain added an answer in America:
    Do you know of an educational institution that wants to acquire printed versions of ecology journals published by the Ecological Society of America?

    I am willing to donate mid-1970s thru 2010+ issues of Ecology, Ecological Monographs, and Ecological Applications.

    Zabed Hossain · University of Dhaka

    The students and faculties of the Dept of Botany, University of Dhaka will be beneifitted by having those journals as ecology is taught in this Dept.

  • Mohamed Aly Elkhodiry asked a question in Fibronectins:
    Does anyone know how can we get peptide amphiphile, PR_b? It is a fibronectin mimicing peptide

    Interestingly, I found some papers discussing the potential of PR_b in comparison with RGD sequences to actively target integrin receptors specific to fibronectin. However, I am struggling to find somewhere that can provide the peptide. Some researchers have synthesized it in their own lab but I am looking for a source where they have it ready.

  • Antimicrobial activity?

    There are numerous papers reported presence of strong antimicrobial activities in medicinal plant extracts. But there are no data about a famous commercial antimicrobial drugs (like antibiotics). Any explanation?

    Saeid Davazdahemami · Research Institute of Forests and Rangelands

    we can look for antimicrobial activities on basis of two aspects in medicinal plants. 1- according to kind of group of chemical material e.g. thymol  which can control some microbs  , these material are exist in ajwan seed and thyme aerial parts. 2- according to kind of  plants e.g. mint family which have antimicrobs properties   

  • How to purify a sulfonated porphyrins or the other organic compounds?

    I have prepared sulfonated porphyrins and purified by soxhlet extraction. But MALDI-TOF analysis showed other impurities. I would appreciate if you could suggest me some suitable method to purify sulfonated compounds.

    Compound is only soluble in water and methanol. Also, I tried to wash the compound with ether and hexane together, but formed viscous stuff and unable to recover as powder.

    Md. Saddam Nawaz · Advanced Chemical Industries Limited

    Solid Phase Extraction (SPE) is known as an excellent purification technique. As your sulfonated porphyrins compunds solubility only in water and methanol, then I feel C18 could be your possible choice for SPE extraction cartridge. Since, I am not aware the full chemistry of your molecule, thus you are also suggested to make SPE cartridges confirm according to your molecule. You can also use MeOH, Water, hexane, ether or their combination as mobile phase during elution of the sulfonated porphyrins molecule from the SPE cartridge.

  • Sarah Boyle asked a question in Apoptosis:
    Methods to Study Apoptosis

    I am trying to study apoptosis in primary mouse mammary cells. So far I have looked at 7AAD/Sytox and FLICA staining by flow cytometry, and upregulation of anti/pro-apoptotic proteins via Western blot. I am now thinking of using the TUNEL assay to assess this. Does anyone have any insights into the best methods for primary cells?

  • Morteza Shabanzadeh added an answer in FC:
    Can anyone help me with a simulation load power management in hybrid power system using PV,FC and Battery

    In hybrid power system consists of PV,FC and Battery sources are used.How to control the load power flow in hybrid system to maintain constant DC bus voltage without interruption supply to the customer.

    Morteza Shabanzadeh · Tarbiat Modares University

    Dear Modem,

    Studying the paper tilted "Grid-connected renewable hybrid system for uninterruptible DC load maintenance" could be fruitful for your research because it gives you a practical sight in the simulation.


    Morteza Shabanzadeh

  • How can I preserved sample of cutanous Leishmaniasis?

    Preserving L.tropica for diagnosis by PCR

    Muhammed oda Mallah · Al Muthanna University

    thank you for your attention