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  • Khodijah Alatas added an answer in Antibacterial Activity:
    If I'm evaluating antimicrobial effect of candy and I incubated it anaerobically. Will the incubation affect the ingredients of the candy?

    I am now evaluating the antimicrobial effect of candy that contain propolis. i diluted the candy on BHI broth as the media of the bacteria. I then added the bacteria and incubating them anaerobically. Will the incubation affect the ingredient of the candy?

    Khodijah Alatas

    Thank you Mr Singh, ill look into it!

  • Khodijah Alatas asked a question in Propolis:
    Does anyone know factors that affecting optical density of bacterial concentration?

    i know the thickness and the colour of the specimen affects the optical density. Do you have any resources for factors that affecting optical density because i do some kind of experiment that evaluating antibacterial effects of propolis using its optical density and standard plate count on agar. but it turns out the result is kinda different. on agar the higher its concentration the greater its inhibition but on its optical density it makes some kind of ^ curve. 

    Thank you.

  • Jyun-Sheng Wang added an answer in FLUENT:
    (FLUENT) I am getting an ACCESS_VIOLATION, Error object: #f when using a UDF to modify the properties of water. How to fix this?


    The UDF is consists DEFINE_PROPERTY functions and is used in an axisymmetric model. I am getting the following error.

    FLUENT received fatal signal (ACCESS_VIOLATION)
    1. Note exact events leading to error.
    2. Save case/data under new name.
    3. Exit program and restart to continue.
    4. Report error to your distributor.
    Error Object: #f

    Can anyone tell me how to fix this problem?



    Jyun-Sheng Wang


    Had you fixed the problem?

    I had written a UDF code for the diameter of Phase2 in the setup page of "Phase."

    The UDF could be compiled, but when I initialize the simulation, a a ACCESS VIOLATION appeared.

    Then I found there was a C_UDMI in the UDF, and I forgot to increase the number of  UDMI locations in "Define→Uer-Defined→Memory...".

    The initialization was OK after I increased the number of UDMI locations.

  • Richard Baby asked a question in Sampling Methods:
    How to do a critique of a report?

    Can anyone give me some suggestion on how to do a critique of the following report in the following areas?

    1) introduction

    2) sampling method

    3) measurement

  • David C Schneider added an answer in Probability:
    What is the difference between bayes test and Neyman-Pearson test in terms of sensing in cognitive radio networks?

    In Bayes approach individual detection threshold are determined for evaluating probability of detection and probability of false alarm while in NP probability of false alarm is fixed. Please explain?

    David C Schneider

    Hello Vatsala,

    With NP inference we set our Type I error (wrong by overinterpretation) at a fixed value, usually 5%.  We protect ourselves from over-interpretations at fixed value, usually 5%.  With Bayesian we state our prior probabilty, we use likelihood to update our prior probability.  Bayesian makes sense if  probability of detection and probability of false alarm are reported as your update of prior results to your result.  

    Bayes and NP inference differ in many ways.  And so you can expect a diversity of replies to your query.

    ~David S

  • Jai Ghosh added an answer in Antioxidants:
    What is the best method for radical scavenging assay (antioxidant assay)?
    Please share your experiences about the advantages and disadvantages of radical scavenging methods from medicinal plants.
    Jai Ghosh

    I Think Dr. Tresina has rightly answered your question and that too in a very elaborative way.

  • Hazim Hashim Tahir added an answer in Science, Technology & Society Studies (STS):
    Is there still a gulf between scientists and ‘intellectuals’? Which of them have more influence on people’s worldviews?

    Traditional intellectuals –thinkers, writers, political and social commentators, and artists- have historically played a major role in the diffusion of the ideas that shape the ways people see the world and their own society and lives

    In the prominent book The Third Culture (1995), John Brockman claimed that these kinds of intellectuals have “become increasingly marginalized”. They are being replaced by scientists who, “through their work and expository writing”, communicate directly with the general public. These “third-culture intellectuals” would be represented by the likes of Paul Davies, Martin Rees, Richard Dawkins, Steve Jones, Daniel C. Dennett, Brian Goodwin, W. Daniel Hillis, Nicholas Humphrey and many others.  

    The culture of traditional intellectuals, says Brockman, “dismisses science”, is “often nonempirical”, uses “its own jargon”, and “is chiefly characterized by comment on comments, the swelling spiral of commentary eventually reaching the point where the real world gets lost”.

    The idea of a Third Culture has its origin in C.P. Snow’s influential “Two Cultures”   essay (1959), in which the British scientist and novelist deplored the “mutual incomprehension” –“sometimes hostility”-- between science and the arts. Scientists shared a “culture” –no matter their political, religious, social class and even disciplinary differences-, with common attitudes, standards, approaches, assumptions and patterns of behavior, At the opposite pole, attitudes were more diverse, but the total incomprehension gave an “unscientific flavor” –often almost “antiscientific”— to the whole “traditional culture”. Moreover, scientists largely overlooked traditional literature, which they perceived as irrelevant to their interests, while most intellectuals were unable to describe something as basic as the Second Law of Thermodynamics.

    Snow saw such disconnection and polarization as a “sheer lose” to society and stressed the need to build bridges between the sides. In a second essay, published in 1963, he suggested that the gap would be closed by a “Third Culture” that would eventually emerge. In his version of this new culture, intellectuals would communicate with scientists.    

    Not long ago, a column in Scientific American stated that Snow’s vision “has gone unrealized” (see Krauss, Lawrence M.: “An Update on C.P. Snow’s ‘Two Cultures’”, August 17, 2009).

    What is your opinion? Is there such a cultural divide? Are intellectuals scientifically illiterate? Do scientists ignore the basics of the humanities? Which of them have more influence on the public? What kind of Third Culture –if any- is emerging?

    + 4 more attachments

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    "The Role of Science and Technology in Society and Governance

    Toward a New Contract between Science and Society

    Here is an excerpt from the article

    Scientists and scientific institutions should    

    • promote multidisciplinary approaches to research, encourage cooperation between the social and natural sciences, and draw lessons from the humanities, local knowledge systems and aboriginal wisdom;
    • encourage a holistic approach to problem solving that takes into account a realistic range of socioeconomic conditions and effects, as well as multiple time and space scales, where appropriate;
    • carefully explain the implications and the inherent limitations of their research findings to the public;
    • fully exploit the predictive power of science to serve social needs with candid awareness of the limitations of scientific predictions;
    • promote the inclusion of scientists from resource-poor countries in international cooperative projects and maximize their access to information and technology;
    • encourage the creation of science-coordination mechanisms at the highest level of the United Nations, fully involving the governments of all countries, as a way to promote integrated responses to global problems."....

    please, see the whole article for details...

  • Adinath M Funde added an answer in Concentrated Solar Power:
    Which is the best material for application in high temperature receiver coating?

    Looking for application in solar thermal technology as receiver in Concentrating Solar Thermal (CST) Systems

    Adinath M Funde

    Thank you Gerro, John and Omer for responses! The articles referred helped me.

    @Omer, I think we also need to consider the stability of material

  • Jai Ghosh added an answer in Chitosan:
    How can I understand which microorganism produces chitosan without extra anything?

    which media for example?

    aspergillus niger is producing i know, but how can they understad this?

    Jai Ghosh

    The references quoted will answer your question.

  • Michael Schmitt added an answer in Surfactants:
    How can I remove a surfactant from polymers (PMMA)?

    I have synthesized poly(methyl methacrylate) in the presence of SDS and would like to know a simple method to remove it from my nanoparticles?

    (large-scale samples)

    Michael Schmitt

    you can remove the excess surfactant e.g. by dialysis. Your particles are a combination of PMMA and surfactant. You may check the charge of the particles by pH dependent zeta potential measurements. 

    • Source
      [Show abstract] [Hide abstract]
      ABSTRACT: Polymer colloids are prepared via radicalic emulsion polymerisation of butylacrylate. Functionalization with amino groups is achieved by copolymerisation of 2-amino-ethylmethacrylates. In order to over-compensate the positive surface charges resulting from the amino groups additionally vinylbenzenesulfonic acid is copolymerized. The size of the resulting particles is controlled by the molar ratio of amino to sulfonic acid groups. The suitability of amino groups for coupling reactions is demonstrated by electrophilic addition of fluorescein-5-isothiocyanate. The resulting particles are characterized by dynamic light scattering and zeta potential measurements as well as by optical spectroscopy. The suitability of labelled particles for optical tracer experiments is demonstrated by fluorescence correlation spectroscopy.
      Journal of Colloid and Interface Science 08/2007; 311(2):425-9. DOI:10.1016/j.jcis.2007.03.026
  • Ahmad Sobhani asked a question in FASTA:
    Need an appropriate script for annotation (NCBI-nr)?

    Hello all

    I am looking for a script for locally annotation (NCBI-nr) of my data on a plant species which we have done de novo assembly on it . Does anyone have any script appropriate in this case? What do you think about this script?

    blastx -query Flower-upregulated.fasta -db nr -out blastx.outfmt6 -evalue 1e-9 -num_threads 40 -max_target_seqs 1 -outfmt 6

    Many Thanks

  • Marie-Hélène Cigna added an answer in Psychopathy:
    Can someone help me with finding articles about primary vs secondary psychopathy and who made this distinction for the first time?

    I need to know more about this distinction and the discussion going on about these two 'types' of psychopathology.

    I also need to know more about the person who first made this distinction in psychopathology.

    Thank you!

    Marie-Hélène Cigna

    I also believe that Karpman was the first one to make that distinction. A really good review is proposed in Patrick's Handbook of psychopathy. Chapter 9 is titled Disaggregating Psychopathy :Where and how to look for subtypes. A section is dedicated to "primary and secondary psychopathy" and reviews the key theories (Karpman, Lykken, Blackburn...) It really helped me! If you don't have access to that book I can scan the pages for you!

  • Mohamed cherif Benzouai added an answer in Investors:
    What are the variables that can measure the risk aversion of investors in a giving country?

    i want to study the relation between risk aversion of investors in sample of counties and their economic growth.

    Mohamed cherif Benzouai

    thank you Mr Faris Alshubiri 

  • Mirabbos Hojamberdiev added an answer in Visualization:
    Can you recommend me crystal structure simulator freeware?

    I need crystal structure simulator freeware for visualizing crystals. Please recommend me one

    Mirabbos Hojamberdiev
    This may help you out.


  • Hemal M Patel added an answer in Knee Osteoarthritis:
    Are Physiotherapy interventions really capable to change the Pathology of Knee Osteoarthritis?

    Almost all the physiotherapy articles on OA  shows clinically significant in management osteoarthritis(Hip & Knee). Whether this significant changes are also capable of changing pathology of OA , so can we believe on each and every articles showing clinically significant ..............?

    Hemal M Patel

    Thank you George Zafiropoulos sir for your answer....... And I completely agree with you.....that its a team work of both Physio and orthopedics ....

  • Debabrata Phukon added an answer in Venomics:
    Is there any work being done on venomics and anti-venomics of arboreal pit vipers of Indian sub-continent?

    There is no anti-venom developed in India against the bite of arboreal pit vipers. I want to know if there is any work or related literature on venom proteins, anti-venomic studies or a correlated study of their systematics in this part of the planet?

    Thanks in advance

    Debabrata Phukon

    Dear Cassio, I have gone through these papers but couldn't find any relevant data regarding my query. Anyways thanks a lot for responding to my question.


  • Carlos Araújo Queiroz added an answer in Electrospinning:
    How can I control the viscosity of the PCL solution in Electrospinning?

    I am doing electrospinng on a X-Y collector. When the fibers collected on the collector it is not in straight line when the collector moves in pattern wise. The fibers are broken. Is there any solution?

    Carlos Araújo Queiroz

    The water-miscible cyclic ethers tetrahydrofuran (THF) or 1,4-dioxane may possibly substitute for dimethylformamide (DMF) as water-miscible solvents of polycaprlactone (PCL). 

  • Mukesh kumar Budhani asked a question in Chemokines:
    What are the basic difference between chemokine and cytokines?

    I want to measure inflammatory mediators in some ailments such as MI, Stroke. Most of the researchers measure inflammatory cytokines and some measures chemokines, so what is the basic difference in between two and is it enough to go for cytokine or both chemokine and cytokines have to measure.Your suggestion will be highly appreciated.

  • Salman Yousaf added an answer in Twitter:
    How to perform "frames in perception" content analysis and sampling of face book comments?

    I am looking to perform "frames in perception" analysis of face book comments. I am looking for helpful articles which could guide my research. Are there any identified "frames in perception" in social media specifically face book or twitter for that matter? 

    Secondly, the sampling of comments is another area of concern. As face book posts in those communities which are selected for this study usually have comments exceeding 5000. Is there any guideline regarding appropriate selection of sample?

    Thirdly, to perform aforementioned two tasks, Is there a better software?

    Salman Yousaf

    Dear Dr. Lidia, 

    Thanks for your reply and helpful link.

    Please do share useful articles related to sampling of facebook comments and "frames in perception" in social media.


  • Jignesh Rajnikant Mehta added an answer in Heat Exchangers:
    Is that insulator foam still necessary for tube heat exchanger if I use PVC pipe for outer pipe?

    PVC is a good insulator. We still need to cover it by insulator foam to prevent heat loss? 

    Jignesh Rajnikant Mehta

    PVC pipe is not as good insulator as say foam.  If temperature difference between the fluid in tube and ambient is not very high, just using thick pipe may be ok.  Otherwise, apply insulation.  Depends upon how many percentage of heat loss you can afford.

  • Soheila Ghambari asked a question in Exploitation:
    How to prevent premature convergence?


    I used ABC algorithm.I know that is good at exploration but poor at exploitation. so I used a method to improve its convergence but it gets stuck in premature convergence ?! which techniques are useful to prevent this problem. and How Can I create a appropriate balance between appropriate and exploration.


  • Aarathi Ganesan asked a question in Governmentality:
    How has the government of india act of 1935 influenced the present conflict between the Central Indian government and Kashmir?

    how has the specific autonomy granted to princely states in the act influenced the constitution of India? can the act be identified as the true source of conflict between the central government and the state of Kashmir?

  • Rishabh Lala added an answer in ETABS:
    Does ETABS allow manual stage construction analysis?

    I'm consistently trying "Stage Loading", the Manual Non Linear Case, as required by my research in ETABS 2015, non commercial version. Although, auto-construction sets are readily applied and analysed but not the manual non linear stage analysis.
    I have completed the procedure with specifying "Stage operations", etc.

    But, deformation display does not show stage wise deformations, as in case of auto construction set, using STEPS in deformation display. Furthermore, autoconstruction set cannot be edited.

    As I need to do non linear stage wise analysis on formulating the time dependent behavior of concrete in terms of creep and shrinkage, is it possible to achieve this in ETABS 2015. If yes, I would be very grateful if you could explain me the procedure or steps to achieve this.

    Rishabh Lala

    Thanks Khaled for reply.

    I would be grateful if you could tell me about a reliable software. What views do you have about MIDAS Civil 2015, can I achieve desired time dependent result along with staged construction in it ? 

  • Md Alauddin added an answer in Gaussian (Software):
    How can I confirm singlet ground (S0) (Three types) and triplet gound (T0) state in carbene (see attached file) using G09?

    How can I confirm singlet ground (S0) (Three types) and triplet gound (T0) state in carbene (see attached file) using G09?

    Md Alauddin

    Thanks all of you for nice explanation

  • Ali Abbasi asked a question in Osmotic Stress:
    How I can exertion salt stress with NaCl in media MS for germination arabidopsis thaliana without action osmotic stress?

    I want measure germination arabidopsis thaliana under 0, 50, 100 and 150 mM NaCl concentration.


  • Coleen Fulguerinas asked a question in SMEs:
    What can you share about MUSTAR INDEX?

    What is the formula for mustar index?

    Is it applicable to the measurement of business growth of SMEs?

    Thank you.

  • Mehrdad Taheran asked a question in Biochar:
    Is there anyone expert in analyzing XRD of activated carbon?

    I have two XRD pattern of biochar. one before activation (BC-M) and the other after activation (AC-M). Now I need help for interpretation. As I know, the structure of biochar before activation is graphite-like sheets in highly disordered form. therefore no serious peaks are expected except a small peaks at around 2theta=26 . But after activation two peaks at around 2theta=26 and 2theta=41 are formed which indicate the turbostratic structure. Can anyone put a more precise interpretation on it?

    thanks in advance

    + 1 more attachment

  • Poonam Takuli asked a question in Plant Extracts:
    How do I perform the hydrogen peroxide scavenging assay with plant extracts?

    I am following the method of Ruch et al, 1989 to perform this assay but Instead of getting decreasing order of OD, I am getting increasing order of OD with the increase of extract concentration. Why it is so????

    Kind regard

  • Gianrocco Tucci asked a question in Physical Cosmology:
    What would serve an "evolutionary effort", if life goes off on time scales much shorter than those of the future existence of inanimate matter?

    Just in relation to this kind of "future", we believe there is a specific contribution of the new vision of the cosmos brought by the Anthropic Principle. This principle will come across a paradox: that of a universe which is recognized "tuned" on the parameters necessary for life Weak Anthropic Principle (WAP), or even declared finalized to the appearance of man Strong Anthropic Principle (SAP), but a universe in which the "window opportunities "for the existence of life and man remains remarkably small. The thermodynamic evolution of the sun does not allow the terrestrial biosphere to maintain perpetually the favorable parameters of temperature, humidity or pressure that now make possible the survival, but will eventually affect irreversibly the conditions necessary for life, preventing the continuation.

    Although this will occur on a time scale rather long compared to the time interval identified from the origin of the human species (though comparable with that identified by the appearance of life on the planet); it is a very short time compared to the history of the cosmos, since the latter is still very young, thus provoking the radical question of why the universe contains in itself, since its genesis, the keys of an opportunity that would then be bound to end well soon

    What would serve this "evolutionary effort", this delicate action of fragile equilibrium, if then life goes off on time scales much shorter than those of the future existence of inanimate matter? Even the possibility that life arose on planets around stars other than the sun, it would leave unresolved the paradox, because the conditions of stability of galaxies (stellar evolution in them) and the cosmos as a whole (cosmological expansion) limit anyway conditions favorable to life in well-defined time intervals.

    It is still a philosophical perspective that would present the SAP as an expression of the evolutionary itinerary of a great law immanent in the cosmos itself, whose ultimate consequences are to generate intelligent life in which, and through which, the universe "takes conscience of itself. "On this it could be argued that intelligent life is the subject of a philosophical reflection even more fundamental, which is not limited to "give voice" to cosmic evolution. As observed appropriately in regard "the fundamental recognition that must be operated by the mind, is not that of a cosmos that proves, investigation, intelligible, but the recognition of our existence depending in a contingent universe.

    It should be noted that the three "solutions" mentioned above are very often presented by their authors as criticisms to the use of the " Principle, use that - as we have seen - does not come necessarily (at least in scientific circles) from the simple data presentation but it is implicitly (and perhaps subconsciously) by now associated with each presentation in the interdisciplinary debate. It is not difficult to see that the major objections to the Anthropic Principle are forced to resort to philosophical arguments a priori. i.e. that are placed on a level of understanding and abstraction that goes beyond the scope of the experimental data from which the same principle, as a question mark, instead arose. As evidence of the philosophical significance of the answers we could cite the pioneering article by Carter (1974), in which the author asserts that "if, by proceeding in this way, it turned out that we got increasingly strict limits [anthropic], and at the same time our attempts to derive those limits by more fundamental mathematical structures should fail, this would be evidence that the philosophy of all the worlds should be taken seriously, even if we didn’t like it "(p. 298). Then, it is not surprising that solutions to the problem, alternative to those of Carter, be always addressed on a philosophical rather than on the experimental level,

    In summary, we believe that the importance of the Anthropic Principle in the arena of dialogue between science lies precisely in the fact that it provides the researcher with elements of reflection on the past because of the real, on the same mystery of being. Taking the start from observations of a scientific nature, it is again examining the role of humans in the cosmos with questions of a philosophical wisdom and, therefore, able to involve it under the existential aspect. Science is not new to the possibility to raise questions "latest" from the inside of its method, although it perceives the inability to give full answer with the only empirical or logical-mathematical tools.

    The elements of reflection offered by the Anthropic Principle appear, from this point of view, among the most challenging for the overall context in which they occur, which is no longer simply that of a science among others, but that of the physical cosmology, stretched in its desire to make the whole universe a single object of intelligibility.

  • Ivan Semernik added an answer in Symbolism:
    How to separate positive and negative symbolic variables of an equation to the left and right sides of the equation in MATLAB?

    for example we have this equation :
    3*a - 2*b + 5*c - d = 0 

    First I need to separate positive and negative variables to both side of equation:
    3*a + 5*c = 2*b + d

    and then take only the coefficient of each symbolic variables:
    3 + 5 = 2 + 1 

    Thank you 

    Ivan Semernik

    For example you can use function "sym2poly":


    Or transform your equation to string format and after this use, for example, "textscan" function to find positive and negative coefficients and separate it: