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  • Ajay Shankar Shukla added an answer in Engineering:
    What is the best TeX editor for LaTeX?
    Give your opinion especially on your experience whether good or bad on TeX editors like LEd, TeXMaker, TeXStudio, Notepad++, WinEdt (Paid), ....

    Some quick ref.
    Ajay Shankar Shukla · Central Council for Research in Ayurveda Sciences New Delhi,Ministry of AYUSH, Govt. of India

    i am using winedt. i think it is userfrndly

  • James F Peters added an answer in History of Mathematics:
    What is the origin and how do we explain the growth of mathematical concepts?

    A.N. Whitehead contended that the science of pure mathematics is the most original creation of the human spirit (Science and the modern world. 1948).

    Number and Geometry appear to be earliest mathematical concepts (see the attached diagram, where N = number, G = geometry). The concept of number has had a huge influence in astronomy, commerce and religion as well as other disciplines.   Geometry has had an enormous influence on agriculture (layout of fields, design of buildings, land surveys, measure, metrics) and philosophy (view of space, dimensionality, permanence vs. impermanence of form, continuity, betweeness, boundedness). Such concepts gradually emerged from a number of cultures in the Middle East, Greece, and in Asia (especially, India and China).  In his history of geometrical methods, J.L. Coolidge, 1940, observed that many mathematicians believed that analytic geometry sprang from the head of Descartes as did Athene from that of Zeus (p. 5).   The attached chart showing the influence of number and geometry on other subjects is incomplete (e.g., physics, chemistry, genetics, engineering, architecture are missing from the chart).


    The concept of a curve has its origin in antiquity and continues to contribute to growth of mathematics.  The attached chart traces the history of the concept of a curve (from R.L. Wilder, AMS talk, 1953).   The story of curvature can be traced back written records in Greece (geometry, Archimedes and others) and in Persia (algebra—Al-Jabr—from treatise by Muhammed ibn Musa al-Khwarizmi, 820 A.D., which originally meant restoration and completion).   See, e.g.:


     http://en.wikipedia.org/wiki/History_of_algebra and https://www.khanacademy.org/math/algebra/introduction-to- algebra/overview_hist_alg/v/origins-of-algebra



    Geog Cantor is credited with introducing the continuous curve concept.  The attached chart is incomplete and needs many more notes to make it more representative of what has happened since the introduction of geometry and algebra more than 20 centuries ago.   See, e.g.:


    http://www3.villanova.edu/maple/misc/history_of_curvature/k.htm and



    James F Peters · University of Manitoba

    @Jaykov Foukzon: "mathematical fantom" means Hilbert's formalism.

    Yes, I see,   Many thanks for the clarification.

  • Kassu Jilcha asked a question in Workplace:
    How can some one prepare a model for workplace intervention using system dynamics tools

    Can you propose me tools that can be used to model workplace safety and health model to prevent incidents and accident at manufactuuring industries of developing countries or else where?

  • Diego Pavón‐Jordán added an answer in Assisted Migration:
    Does anyone have any examples of assisted colonization, managed relocation or assisted migration in plants?

    Collaborations may be forthcoming if I can find anyone working on plant assisted colonization.  It can be anywhere in the world and any habitat.  I want to try out a decision framework recently published on AC and the biogeographic approach.

    Diego Pavón‐Jordán · University of Helsinki

    You may also want to look at Maria Hälfors et al.´s work for boreal plants at the Finnish Museum of Natural History.

  • Rick Farrar added an answer in Botany:
    What is this plant?

    this is climber.

    leaves single, lenceolate and alternate.

    Rick Farrar

    Not sure where you are, but in my former home (State of Arkansas in USA) I'd think first of Ipomoea pandurata.

  • Mohamed El Naschie added an answer in Physics Theory:
    How to locate the truly non-trivial but inconsistent theories in History of Physics... ; or to what extent Nature tolerate contradiction and why...?

    One of the intriguing areas of wider philosophical interest gaining currency during the last two decades or so is the pursuit of paraconsistent logic. The expression is well known to have been coined by the Peruvian philosopher Miro Quesada (Third Latin American congress on mathematical logic, 1976) as an answer to Newton da Costa looking for a good name for the systems he was working on. Paraconsistent logic is concerned with deep philosophical issues regarding the nature of negation and Reality..
    After I participateded the fifth world congress on Paraconsistent logic held in Kolkata (13th-17th Feb, 2014), it seems really fruitful to approach some of the inconclusively debated issues in History of Science from within a paraconsistent framework. The issue is precisely to make sense of a physical analogue of contradiction … and to ask to what extent Nature can (/needs to) tolerate ‘these analogues’ to be accommodated in Physical theories.
    Put in other words, the issue is to take a fresh note of possibility to characterize some of the key moves in history of Physics as truly non-trivial (effective) but logically inconsistent..!

            With this much  background in view, the best questions to start with are perhaps -

    - What about the ontological significance of Laws of Physics in connection with the notion of IS ? / Why the Laws of Physics are the way they are?
    - Should we believe the Laws of Physics as ‘ true mechanism’ capturing Nature’s objective scheme … ?
    - How Contradiction of different orders seems to be hosted in formulating Laws of Physics.. , particularly in quantum mechanical domain?

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

    Dear respected colleague- I am  extremely interested     tin his subject about which I  heat now for the first time. In fact if  human behaviour theory  is  collerated to physics then it must have a place in science. How else could we explaine the madness of world war one and two,the korean war, vietnam war, the destruction of Iraq and now Syria  let alon the arab israili wars  and all that by highly scientific countries  professing to act logically  not  paraconsistent logically .

  • Diego Hernán Valencia Korosi added an answer in Sustainable Development:
    Is there any measurement model to measure the eco tourism?

    Dear All. I am Planning to Start my Mphil. it is about Eco Tourism and the Sustainable Development. Please share any measurement model for measure the Eco tourism and Sustainable Development. Further if there is any research area in addition to that let me know.


    Diego Hernán Valencia Korosi · Universidad Nacional Autónoma de México

    HI Umesh, 

    I believe that understanding the principles of ecotourism, from its origins (Carlos Ceballos-Lascuraín 1986) to current trends, issues and coinstraints (Carter 2006, Martha Honey 2008, Ralph Buckley 2004-2012) will give you a good picture of what to measure. As any other tourism activity, ecotourism can be measure quantitatively in terms of profits from visitors, etc. Or you can use  surveys, and/or interviews to ecotourism stakeholders, ecotourism government officials, and guests at the ecotourism destinations to understand what an ecotourism venture should contain. 

  • Tzu-Heng Chen added an answer in SPR:
    For metal nanoparticles dispersed in a solvent how does the particle size correlate with the SPR peak ?

    For two different process conditions I have got silver nano particle suspensions with SPR peak at 410 nm and 420 nm. But the average particle size is 15 nm. Whether it's in agreement with any existing correlation ?  

    Tzu-Heng Chen · National Taiwan University

    The SPR not only depends on the size and shape but also the dielectric constant of its environment.(i.e. solvent or ligand)

  • Harold DeLisle added an answer in Snake Bites:
    Why do snakes bite people sleeping in their homes in rural areas?

    Do you have any experience of nocturnal snake bites? Why do snakes enter houses of people during the night? Most neurotoxic bites in our state occur during night while people are sleeping. Bites have been seen to occur between 12:00 am to 6:00 am. 

    Harold DeLisle · Moorpark College, California

    I live in a rural area (desert) with lots of snakes. Few venomous ones.  I have never had one enter the house, but often in the summer I find them in sheds on the property. I hear that snakes sometimes come in houses here through gray-water pipes that lead to the inside.  I second the opinion that snakes to do bite unless provoked. If a snake gets into a bed and someone rolls over on top of it, snake bite would likely follow.

  • Prabhat Kumar Upadhyay added an answer in Chalcones:
    Is there any chances to get anti fungal activity from chalcones and its related compounds?

    if it has that activity please explain 

    Prabhat Kumar Upadhyay · GLA University

    Least favourable, but  moderate activities were observed.....

    Jaya kishore told and gave information relevant to it, found significant value in research.

  • Zubayer Ibna Zahid asked a question in FRP:
    Can anyone provide me with best suitable references on parameters affecting shear strength of FRP RC Beam?

    We know that, Shear Strength is mainly affected by 5 parameters. They are,

    1) Concrete Tensile Strength

    2) Shear Span to Depth ratio

    3) Longitudinal Reinforcement Ratio

    4) Beam Size and

    5) Axial Force.

    I need references specifically about the parameters that affects shear strength of FRP RC Beam. Thank you in advance.

  • Ali Övgün asked a question in Magnetism:
    What is the information? Is it physical? Are there any information particles? Are there any information bosons which carry the information?

    Mathematically, a system’s information content can be quantified by the so-called information entropy H, introduced by Claude Shannon in 1948. The larger the information entropy, the greater the information content.1 Consider the simplest possible information-storage device: a system with two distinct states—for example, up and down, left and right, or magnetized and unmagnetized. If the system is known with certainty to be in a particular state, then no new information can be gained by probing the system, and the information entropy is zero. An interesting question, then, is whether the thermodynamic consequences of the second law extend to information. Is it possible to extract useful mechanical work from a system just by observing its state? If so, how much? And at a more fundamental level, are the thermodynamic and information entropies related?

    Are there any information particles? Are there any information bosons which  carry the information? Is the information fundemental ?

  • Bikramaditya Kumar Choudhary added an answer in Social Support:
    How we can address the problems of nutrition in the elderly population?

    Elderly population is mostly vulnerable to the various nutritional problem, which is not only because of the physiological aging process, but also due to the lack of social support especially where children left the parents for a job in any other city or country.

    Bikramaditya Kumar Choudhary · Jawaharlal Nehru University

    The nature of state and distribution of power are important aspects needed to b included in the study of elderly and the issues related to elderly. The over-arching generalization of indicators and measures of nutrition in my opinion has limited bearing on actual nutritional status. It would be far more important to incorporate local ecologies, available plants, herbs and the nature of ownership on these would make study of nutrition an more robust. Sometime, we miss the basic conception in order to select suitable measure that can be quantified.   

  • Morgane Aubineau asked a question in Asperger Syndrome:
    Is it relevant to use Friendship Quality Scale (Bukowski, Hoza & Boivin, 1994) without the dyadic nomination?

    For a study, I’m about to use a french version (translation Eng>French and back translation) of the Friendship Quality Scale (FQS; Bukowski, Hoza & Boivin, 1994) for students with Asperger syndrome in mainstream secondary schools.

    By using this tool, my goal is to see how those students perceive their relationship with the person they choose as “best friend”.

    Because I’m interested in the personal view of the student, I don’t need to confirm if this relationship is reciprocal in all ways by the person identified as “best friend”. Moreover, it would be difficult to ask this “best friend” to complete the questionnaire if (s)he’s not participating at the study. I have to clarify that FQS is one of the tools I am using in this study. An important part will be semi-directive interviews with those students.

    Nevertheless, I would like to collect your opinions about the relevance of using the FQS without involving a dyad student / best friend.

    Thank you for your help.

  • Pablo Andrés Riveros Muñoz added an answer in Polystyrenes:
    How can I clear a blockage of densely packed polystyrene spheres in a microfluidic channel?

    I have a 3 cm long microchannel with a cross section of 30x20 um . The channel is etched in silica with a glass coverslip glued on to form a lid. I am flowing 5 um polystyrene spheres in buffer down the channel but after a while the beads clog and form a plug blocking the channel. Does any one have a method to remove the plug ? I have try flowing acetone and toluene but it does not dissolve the beads. Thanks!

    Pablo Andrés Riveros Muñoz · Centro Universitário Fieo

    Try to increase the temperature to melt the PS (230°C) and pump neat material until clean the channel.  If you prefer use solvents, use acetone, but the solvig process take about 24h,probably more in your case because you channel is quite deep...

  • Tzu-Heng Chen added an answer in Carbon Nanotube Synthesis:
    Which organic solvent is best for dispersing carbon nanotubes into silicon resin?

    I am looking for a suitable organic solvent not only to disperse carbon nao tubes but also miscible with Silicon resin. I know from my earlier study DMF(N,N dimethyl formamide) is a good choice to disperse CNT but it is not miscible with silicon resin. Any suggestions are well come?

    Tzu-Heng Chen · National Taiwan University

    NMP is a good choice, toluene is also worth to try

  • Samira Amiri asked a question in Illumination:
    What is the spectrum width for 1310nm?

    in a paper mentioned that illumination near 1310nm.... Who know the start & stop wavelenght for illuminating? (the results are in range of (1200nm-2000nm)...

  • Raoof Mostafazadeh added an answer in Hydrological Data Management:
    What are the different effects of length of data records in hydrological analysis?

    From the frequency analysis, data and statistical analysis point of view.

    Raoof Mostafazadeh · Mohaghegh Ardabili University

    @Gianni, Well said,

    Just some notes

    The length of records strongly affects the results of frequency analysis and calculated Recursive Intervals, RI.

    The variation of the recorded data and physio-climatological nature can determine the minimum required length for acceptable estimates. According to Subramanya (2000), a 30-yr recorded data is needed and less that 10-yr data is worthless in frequency analysis. The more the better (in homogeneous and reliable data). The assessment of reliability or test of homogeneity is required for long time series (As mentioned by Gianni).

    Avoid estimating RI flood values that are greater than TWICE the record length. Estimates of flood RIs can be done with relatively short records (less than 10-yr). The needed length of record within either ±10% or ±25% errors across different RIs is given in the attached table.

  • Sabine Strehl added an answer in Cytogenetics:
    Why i cant find my metaphases after m fish preparation ?

    i prepare slides with typical cytogenetic precedures. i find lots of good metaphases in the microscope and then i start the mISH experiment. But when i want to focus to the visible light in the microscope i can not find any of them. in witch step might i lose them. Generally i use my slides in different concentrations of SSC, In NAOH for denaturation, in ethanol series(70%,95%,100%) and in SSC with 0.05% Tween

    Sabine Strehl · Children's Cancer Research Institute

    Try to use formamide in 2x SSC for denaturation instead of NaOH. And dehydrate your slides in throughand  ethanol series before you start with the FISH procedure.

  • Muhammad Kamaal Khan added an answer in Palatine Tonsil:
    How long would you monitor children with asymptomatic unilateral tonsillar enlargement?

    Most systematic reviews and case series recommend following up children with asymptomatic unilateral tonsillar enlargement as 73% of tonsillar lymphomas present with unilateral enlargement of palatine tonsils.

    Muhammad Kamaal Khan · North Cumbria University Hospitals NHS Trust

    Thanks Béatrice. 



  • Kassu Jilcha asked a question in Workplace:
    How can I model workplace intervention using neural network and genetic algorithm?

    How can I model workplace intervention using neural network and genetic algorithm?

  • Linh Nguyen asked a question in Nonlinear Models:
    What are the differences between Plastic hinge and Nonlinear Spring hinge in nonlinear model for Beam and Column?

    What are the differences between Plastic hinge and Nonlinear Spring hinge in nonlinear model for Beam and Column?

  • Partha Sarathi Swain added an answer in Cattle:
    What are the new approaches of animal nutrition sector?

    This question is with regards to cow and sheep nutrition.

    Partha Sarathi Swain · National Dairy Research Institute

    i think still so many grass root level problems are still not addressed,... if we can eliminate these problems and that will boost our productivity  and food security

  • Hoda Hajian added an answer in Cointegration:
    Why do I obtain very different results for Johansen cointegration test using different lags?

    one example: using 1 or 2 lag there is 1 cointegration relation. But using 3 lags or more there is no cointegration relation. In another example the cointegration relation test is significant only in higher lags (3 and more).

    Hoda Hajian · Putra University, Malaysia

    Thanks a lot for the answers....

    Dr Francis Ahking: Thus, it means that a robust model gives rather similar cointegration result with different lags! and the model I am using is misspesified in a way.

  • Cheuk Him Ho asked a question in Physical Chemistry:
    Please provide examples for this. Is there any strong relation between different science subjects (such as physics, chemistry, biology, maths, etc)?

    Relation between different science subjects. Use examples for proofs. 

  • William Letter added an answer in Buffer:
    How can we load less sample in a Sample loop of AKTA Explorer?

    Can any one please give me idea how we can load less sample in a loop? For an example we have a 10mL loop but we have 5 mL of Sample but we do not want to dilute the sample with WFI or any other Buffer, how we can inject the sample without any bubble in the Column in the AKTA Purifier/Explorer.

    William Letter · Chiralizer Services, LLC

    The manufacturer sells injection loops in different volumes for this exact application (0.500 ml, 1 ml, 2ml, 5ml, 10ml, 20 ml...). Loops are meant to be switched out to best suite your own application and it is a good idea to have several sizes on hand. Purchase a few different sized loops so you will have more injection options in the future (they are inexpensive and you can make your own loops if you have some tubing, proper fittings and an analytical balance to calibrate them).

  • Libor Trško asked a question in Ultrasonics:
    Does anybody know a software capable of calculating resonance frequencies of solid parts?

    I am searching for a software used for example for design of ultrasonic tools. I need to be able to define my own model, own input material properties and be able to obtain results about resonance frequencies in the longitudinal tension - compression mode.

  • Ulrich J. Hammerich added an answer in Market Development:
    What are the major determinants of the level of stock market development?

    For example, what are the major factors that influence whether or not a stock market achieves weak form/ semi-strong form market efficiency?

  • Masita Misdi added an answer in Employment:
    In times of financial crisis, what would the purpose of vocational education be?

    In times of financial crisis, would vocational education help students to prepare for "more and better employment opportunities" or "fewer difficulties in finding employment"? These are quotes from two different education policy documents. Could you recommend studies addressing the financial crisis and vocational education?

    Masita Misdi · Southern Illinois University Carbondale

    Dear Joanna,

    This question is really interesting.  I agree with Emerson Abraham Jackson:

    "no matter what the situation may be is still heavily reliant on wealth created from those working in vocational trade or industries".

    and or course Germany is the country in my opinion that lead the vocational education with their dual system.  They are in a way has given a good image to the vocational education.

    Vocational Education should not be viewed as a second class education. In fact if we really think deeper, most occupation deals with certain skills.  The skills are mastered by routine practices and training.

    To answer your question whether vocational education "prepare more and better employment opportunities" during financial crisis or "fewer difficulties in finding employment", depends on the skills that every one of us possess. Entrepreneurship is one of the way to survive during the financial crisis. If you cannot get job anywhere, you can use the skills that you have (providing other generic skills such as problem solving,critical thinking, creativity are there as well) to embark into small enterprises.  Coming from home economics background, my example would be like creating your own catering based on the cooking skills that you have.  Also, other alternative is to get new skill during the financial crisis and start on the life long education experience.  I have read a short article about whether financial crisis is actually help or hurt vocational education. something for us to think about.


  • U. D. Chavan added an answer in Food Biochemistry:
    Is there a correlation between antioxidant activity and mineral content?

    Is there any correlation between antioxidant activity and Mineral content in food material?

    U. D. Chavan · Mahatma Phule Krishi Vidyapeeth

    Yes, some minerals not directly but indirectly inhance the activity of the other compunds and increae the antioxidant activity.