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  • Stan Karanasios added an answer in Activity Theory:
    Can anyone share sources that critique Activity Theory?

    I am struggling to find sources that critically appraise Activity Theory as a framework for conducting research. Please share if you know any.

    Stan Karanasios · University of Leeds

    Hi Kevin,

    Could you please post a link to your book, if it is published please? It looks interesting.

  • Anil Pathak added an answer in E-Learning:
    Is there anyone who has any source regarding Web based learning?

    My Research title is Enhancement of READING and WRITING skills of an Engineering students through WEB BASED LEARNING TOOLS. I would like to know some web based tool's name. 

    Anil Pathak · Brunei Institute of Technology

    Here are two links related to your research topic:



    All the best :)

  • Pravin M Ganorkar added an answer in Food Safety:
    What are the standards for lemon Marlade preparation?

    We preparing Aloe vera pulp based marmalade. We need standards as per the Food Safety and Security act.

    Pravin M Ganorkar · A.D.Patel Institute of Technology

    Dear Vallabh Sir,

    Marmalade specifications given in FSSAI is as follows

    2.3.34 Marmalades:
    1. Marmalades means a product prepared by boiling sound fruits with peel, pulp and Juice, with or without
    water, added nutritive sweeteners and concentrating to such a consistency that gelatinisation takes place on
    cooling of the product. It shall not be syrupy, sticky or gummy and shall be clear and transparent.
    2. The product may contain food additives permitted in these regulations including Appendix A. The product
    shall conform to the microbiological requirements given in Appendix B. It shall meet the following requirements:—
    (i) Total soluble solids (m/m) Not less than 65.0 percent
    Fruit content except peel (m/m) Not less than 45.0 percent
    Peel in suspension Not less than 5.0 percent
    3. The container shall be well filled with the product and shall occupy not less than 90.0 percent of the water
    capacity of the container, when packed in the rigid containers. The water capacity of the container is the volume of
    distilled water at 20 degree C which the sealed container is capable of holding when completely filled.

    For more details, please refer
    FSS (Food product standards and Food Additives) Regulation, 2011 (part I) 

  • Pavan Hiremath added an answer in Marine Corrosion:
    What is the better organic coating to prevent from the marine corrosion?

    Several organic coating exist based on epoxy, benzoxazine or other high performance thermosets, blends and particles reinforcements are also used to enhance the anti-corrosion properties. My question is: among these multiple choices what is the better organic coating used in naval industry?

    Pavan Hiremath · Manipal University

    Mr Derradji

    There are many resins in epoxy family which exhibit good water resistant property. Following are some of the links where you can get complete details about your search.




    I hope this will be helpful for you

    good luck

  • How to do interesting activities for students of dentistry?

    Very thankful for your attention.

    Agnieszka Osmólska-Bogucka.

    Mariela Padilla Guevara · Latin American University of Science and Technology - Costa Rica

    In our case, everything related with communities engagement is always a success!  Significant experiences are those were you can link the learning with service.

  • Akila Wijerathna Yapa added an answer in Y2H:
    How does 3-amino-1,2,4-triazole (3-AT) works on Yeast two hybrid analysis?

    How addition of 3-Amino-1,2,4-Triazol (3AT) : inhibitor of the HIS3 reporter gene is function on screening of Y2H transformations?.

    Akila Wijerathna Yapa · Wayamba University of Sri lanka

     Thank you Dr. Liger for your suggestion

  • Mohamed El Naschie added an answer in Sun:
    Does all the suspended matter in this cosmos is due to the effect of magnetic field ?

    Qn 1. Is there any other field/force which is also responsible for suspension of these matter [ planets ; star ] in the space. If so then, what is the composition [ theoretical or experimental view ] of the force which makes them in suspended form with spin and orbital motion.    

    Qn 2. Let us assume that the known planets in solar system is revolving around the sun with an effect of magnetic field , in such case what factor decides the distance of separation from the planets to the sun; is it some sort of material based [ like Fe is attracted more to strong magnet than Ni ] ; let us assume that all the planets were chips extracted form the sun ; in such case whether the extracted planet will have individual core matter to be controlled by sun for its orbital and spin action

    Qn.3 Does geomagnetic Strom has any effect on orbital/spin action of the planets ; if so , at what extent it has an effect on the motion of planets.  

    Mohamed El Naschie · Alexandria University Alexanderia Egypt

     THESE are  ORIGINAL Question but as far as i understand out side established scientific or if you want dogma. of course there may be many yet to be discovered fields but planets are not suspended in a magnetic field  in my current understanding even though i think electromagnetism is more fundamental than gravity 

  • Radhouene Doggui asked a question in Potentiometer:
    Problems of analyzer using potentiometic method for urinary iodine determination?

    Any one use direct potentiometric determination of iodine in urinary matrix?

  • Raimy Haidar asked a question in Abaqus:
    How to solve these issues (Frequency Extraction & applying load problem ) - ABAQUS?

    Dear friends,

    Currently im having two issues and uncertainties regarding on Abaqus analysis process:

    i. Does Abaqus CAE has the capability to perform linear perturbation of Frequency and Modal analysis with the action of g= 9.81m/s^2 towards the whole model? 

    ii. How to apply load on a specific location, where the point does not appear in Abaqus? (as shown in attached figure) , Is there any solution to create a node on that location ? 

    Helps needed, best regards.

  • Nuno M. Silvestre asked a question in Type Theory:
    Ions in LCs with meanfield. Is it done?

    Has anyone ever modeled ions in liquid crystals with Landau-de Gennes type theories?

  • Ellie Prior asked a question in Hearing:
    Should I use a graph for my project or is using a table enough?

    I do not know a lot about statistics and am trying to get my head around how I should present hypothetical data for my research project. I am measuring the difference in the conversations of hearing-impaired+hearing dyads to hearing+hearing dyads in primary school. One of the hearing children will be the same in each pair and the other hearing child will be matched to the deaf child on a range of factors (i think this means it is a repeated measures design which i am counterbalancing) I am measuring:

    Number of turns
    Number of utterances
    Mean length of turns in utterances
    Mean length of utterances in words
    Unintelligible utterances
    Nonverbal turns 

    further, I am then measuring within the turns:

    Number of initiations
    Number of simple responses
    Number of extended responses
    Number of disruptive responses

    I have been using the statistics book 'How to design and report experiments' by Field & Hole 2003 and so far think that my data is ratio, the descriptive stats should be mean and SD (assuming normal distribution) and t-tests for matched samples will be used for inferential stats. However the past papers I've read use graphs to display the data and but I am unsure how I would do this as I can't think of a way to display this data on say a line or bar graph without creating loads of graphs so currently my info is displayed in table format... any help would be much appreciated. 

  • Sergei Filippov added an answer in Field Emission:
    What do you know about early history of field emission theory (except well-known facts like FN equation)?

    I'm interesting in early history of filed emission, especially in field emission science methodology. Does anyone have appropriate materials?

    Sergei Filippov · Ioffe Physical Technical Institute

     Professor Cahay

    Thank for your reply! It was very helpful for me.

  • Joakim Klar added an answer in Ion Torrent:
    Is anyone familiar with Pooled DNA for exome sequencing?

    I'm not a big fan of using pooling but we are actively discussing it as a mutation screening approach. The benefit would be reduced cost but with the drawback of limited depth per chromosome. The key issue here is to allow detection of single nucleotide variants even in heterozygous form from each individual within the pool. What is your experience? Ion Torrent, Illumina. Best /Hans

    Joakim Klar · Uppsala University

     The problem would not be coverage, but variant calling. Consider the number of false positives/negatives when calling a heterozygous variant in one of the samples with a theoretical number of reads equalling 25%.

    Also, to sufficiently call a heterozygous variant you need 33x on target coverage, preferably x80, meaning one would probably miss a lot even with an average of x160 times coverage.

  • Martin Willis added an answer in Foreign Languages:
    How is important top-down processing when visiting a foreign language speaking country?

    I am currently writing a reflective networking essay on the way in which top down processing is used while visiting a foreign language speaking country. Any input?

    Martin Willis · Tokyo Woman's Christian University

    I'm not sure that I agree that "top-down processing is another term for deductive logic". To me, top-down processing is basically the use of existing knowledge/beliefs to interpret things you do not understand. At its worst, it can represent inflexible, preconceived notions, and I would suggest that that is more likely lead to judgements like "it disgusting to eat chicken feet, so Chinese culture is disgusting" than any bottom up judgement. The danger with bottom up judgements is the creation of generalisations on the basis insufficient evidence. 

    Sahriya, I think it would be probably be easier to answer your question if you could tell us what you think top-down processing when visiting a foreign language speaking country might be good for. 

  • Which heuristic optimization method is the simplest and easiest to use?
    Many heuristic optimization methods (see:
    https://www.researchgate.net/post/What_are_the_recently_invented_Evolutionary_algorithms_EAs_Optimization_method_Which_method_you_found_en_effective_method#share )
    have many parameters that are difficult to tune. And this is a big problem in their use. You never know whether the parameters have their optimal values.
    I prefere methods with the smallest number of parameters which are easy to tune (see
    http://gdudek.el.pcz.pl/files/TourSearch_14.pdf )

    What are your opinions and experiences?
    Iliya Bluskov · University of Northern British Columbia

    I believe I have a metaheuristic which uses no parameters, and needs no fine tuning; check it here:


    Journal of Combinatorial Optimization, 2015, DOI 10.1007/s10878-014-9826-x.

    The final publication is available at link.springer.com; more precisely, here:


  • Ahmed Ali added an answer in Cystoscopy:
    Why does the mare show frequent urination,can it be Cystitis/Calculi ?

    A mare ageing 5years, foaled once, shows yellowish turbid urine since last 4 months. The mare voides the semi solid creamy chalky material from urinary bladder. The urination is frequent and it soils the both hind limbs, the skin got stained and seems to be burned but urine is alkaline (pH-9 on pH paper). On laboratory examination it showed crystals of calcium oxalate. The blood values are in normal range except BUN-45. The feeding and watering habit is normal and not affected. USG of bladder showed snowy-hyperechoic image with thick walled bladder. Cystoscopy showed yellowish hazy mucosal surface.

    What could be condition, reason for this and line of treatment?

    Ahmed Ali · Qassim University

    frequent urination of mare is a sign of




    But your finding in this case (lab+sonar) lead to clearly the first suggestion (cystitis).

    Prolonged treatment regimes are essential since relapses are common because of dormant bacteria in the bladder wall. Bacterial cultures of urine and antimicrobial sensitive testing of cultured bacteria will help the veterinarian determine a course of treatment. Penicillin and trimethoprimsulfa are often used to treat the affected horse with good results.

    for more details



    Good Luck

  • How can I calculate Lm/W value and Cd/A value of an OLED?

    Can anyone explain how to calculate Lm/W value and Cd/A value of an OLED? Also how to calculate the EQE and IQE of an OLED.

    Justin Jesuraj · Bharathidasan University

    Hi das, 

    I am using ocean optics USB2000+RAD spectroradiometer, it first measure intensity peak position, later i have to use absolute irradiance measurement (which itself in the spectrosuite software which i used) to convert the received intensity into lumen or Cd/m2 (lumen=cd/m2 only if sterdian is = 1). 

    After calculating the lumen (or cd/m2) value, you can divide it with current density (in A/m2), it gives current efficiency in Cd/A.

    then it is similar to power efficiency (lumens/watt), instead of J you have to use P(V*i).

    you have to check in your software where it helps to find absolute irradiance measurement, 

  • 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.

    Graeme, Arnold and Louis (and perhaps Tausif?),

    About this so-called distinction between 'access'consciousness and 'phenomenal' consciousness have you read Sid kouider et al's response to Ned Block "Do we still need phenomenal consciousness? Comment on Block" in Trends in Cognitive Sciences (March 2012)?

    In particular what do you think of the following authors' comment: "Ned Block confronts the recent empirical and theoretical challenges to his distinction between two forms of consciousness (i.e. rich ‘phenomenal’ vs sparse ‘access’). Although we value his attitude of facing these issues, we still believe that the proposed ‘unaccessed phenomenal consciousness’, which is the cornerstone of this theoretical proposal, remains unfalsifiable and can be accounted for by other, more parsimonious, explanations".

  • Oded Liran added an answer in Algae:
    Why should microalgal cells be adapted to CO2 in high concentration?

    As scientific researches demonstrated that micro algae should adapted to Co2 in high concentration.

    Oded Liran · Tel Aviv University

    At 25% CO2 mix with air  the algae deal with extreme medium acidification. This field is beyond my area of expertise but if I had to throw an educational guess i'd say that at such acidic conditions the algae will invest enormous amount of energy to keep homeostasis ( which will probably kills them... making CO2 toxic eventually) and so the CO2 removal pathway will be secondary to any effort to stabilize their internal pH.

    A supreme reference for carbonic acid kinetics in water is Wolf-gladrow book : CO2 in sea water- a good friend along this way.

    Hope this information helped, 

  • Iliya Bluskov added an answer in Hyper Heuristics:
    Is there really a significant difference between the performance of the different meta-heuristics other than "ϵ"?

    Is there really a significant difference between the performance of the different meta-heuristics other than "ϵ"?!!! I mean, at the moment we have many different meta-heuristics and the set expands. Every while you hear about a new meta-heuristic that outperforms the other methods, on a specific problem instance, with ϵ. Most of these algorithms share the same idea: randomness with memory or selection or name it to learn from previous steps. You see in MIC, CEC, SigEvo many repetitions on new meta-heuristiics. does it make sense to stuck here? now the same repeats with hyper-heuristics and .....   

    Iliya Bluskov · University of Northern British Columbia

    I was one of those tired of looking through all kind of behavioral schemes borrowed from physics, chemistry, biology, zoology, and trying to adjust the parameters to beat a problem, so I came with a metaheuristic (PDO) that does not depend on anything, but the problem itself. I do not claim it outperforms any other method in any possible problem, because I have not experimented long enough and extensively enough; plus the NFL is lurking around, but PDO is simple enough to implement, does not need any adjustment of parameters, so it might be better than few others, in a sense:


    Journal of Combinatorial Optimization, 2015, DOI 10.1007/s10878-014-9826-x.

    The final publication is available at link.springer.com; more precisely, here:


  • Harish B M added an answer in Ligand Binding Assays:
    What can I do when I have trouble with my ligand on autock tools procedure?

    Can anyone help me on this please?
    Once the protein is prepared, when I open the ligand and try to do the torsion tree part, I get an alert box saying that I must select a ligand first. I can't understand why this happens because I already have the molecule I want selected in the left options of the dashboard. What am I missing?

    Thank you!

    Harish B M · Bangalore University

    In MGL tools you always open ligand through Ligand>input>open file, if already present in work space, if u need to prepare ligand, if it ask to select ligand first, then you goto Ligand>Input>Choose option,  and under choose, you select your ligand and prepare you molecules.

  • Oleksandr Stoianov added an answer in LC-MS:
    Does anyone have experience with LC-IRMS from Thermo Fischer?

    I have problem with "pump blocked" (mostly with Ox. Pumb)

    Oleksandr Stoianov · University of Tuebingen

    How ofthen do you change the frit? I use concentration of Na2S2O8 - 125 g/500 ml H2O. Is it high? Can it be reason  for blocking pump (because of frit ) again?

  • Is Eunice indica a pollution indicator species or a warning sign for an area that is stressed?

    In Ennore creek in Chennai, TN, India. people engaging for harvesting Polycheates. Near about 400 poor coastal people were collecting for livelihood  and each person sold it for Rs 1000/kg for prawn brooders in aquaculture industry. It is mainly a pollution area were discharge of industrial effluents and domestic sewage are mixing and i noticed only one species is dominant in that area. If please any body identified species. I doubted Eunice indica ?

    Muthuswamy Jaikumar · ICMAM-PD , Integrated Coastal Marine Area Management, Chennai

    Thank you Sir 

  • Why does my graphene oxide solution turn to green instead of yellow at H2O2 addition stage?

    after adding KMnO4 it is dark brown and I had left it for 24 hours in order to complete oxidation ...but after I had diluted the solution with water and  added H2O2 it turned to green instead of yellow!... I guess it is for the short time of oxidation or the quantity of H2O2...would you please help me with this? ( I am using Hummer's method with modification of removing NaNO3)

    Seyede Farzane Besharat · Tarbiat Modares University

    Thank you dear Aisha...I will do that... I have synthesized another sample a few days ago and I have left it for 4 days before adding H2O2 ...and surprisingly I saw that even before H2O2 addition the stirred solution was green again!...That's weird because at first it was dark brown (  + a little dark green) but after 4 days it got totally green which wasn't that much dark...

  • Amitkumar Pramanik asked a question in Android:
    How to make android app that receive command from matlab at remote location connected of internet??

    android app receive command from matlab over internet

  • Can anyone suggest me, what studies can be performed after molecular dynamics simulation studies?

    we have completed our work till molecular dynamics simulation studies for protein ligand complex. I want to know in what way can studies be continued after molecular dynamics simulation studies.

    Parastou Rahimizadeh · Azarbaijan Shahid Madani University

    it can be very interesting and approvable if you do your work in labratory scale. you can investigate protein ligand interaction in molecular lab.proteins have synetic and properties that you can determine them in molecular project.

  • Kritika Sharma added an answer in Biodegradation:
    What is the procedure for calculating COD after biodegradation and what should be blank for calculation?

    Can anyone provide detailed method for COD calculation after biodegradation of effluent sample and which kind of blank should be use for this? 

    Kritika Sharma · The Central University of Rajasthan

    Thank u so much sir.

  • Can anyone suggest papers where data mining classification algorithms are compared?

    comparison considering accuracy, error rate, precision and various related factors.....

    Qasim Mohammed Hussein · University of Tikrit

    ) Comparing classification algorithm in data mining , Sampson Adu-Poku , Master thesis.

    2) A Comparison Study between Data Mining Algorithms over Classification Techniques in Squid Dataset, Article

  • Martin Jaeger added an answer in Blended Learning:
    How do faculty handle group work challenges in higher education and with what success for f2f, online, and blended classes?

    Assigning collaborative assignments are expected in the 21st Century classroom for developing students' collaborative skills. But, research has shown that orienting group work to a successful completion is not any easy task to achieve for both students and teachers in f2f, online, and blended classes.

    Martin Jaeger · Australian College of Kuwait

    We had good experience with online based collaborative assignments. First, the individual contributions of individual group members were easy to identify, and, secondly, online based collaboration simulates many workplace situations more realistically. See for example the attached work.

  • Does anyone have experience with 3T3-L1 adipocyte differentiation?

    I m trying to differentiate 3T3-L1 adipocytes. Can anyone pls tell me, how many days it take for complete differentiation. I differentiated it for 8 days using standard protocol, but i didn't observe adequate differentiation, which was confirmed by Oil-red O staining. Any suggestion?

    Selami Demirci · Yeditepe University

    Passage number 22 is normally too high. Even you may observe some lipid droplets at the end of differentiation period, it is not even comparable with the differentiaton conducted with early passage cells. One additional issue is passaging protocol. You should never reach over %80 confluency during expansion. Otherwise, cells lose their differention capacity even if they are at early passages. If you overgrowth cells in any passage, you should get rid of them and buy a new batch. Therefore, if the cells are forced to differentiate by either DMI or overgrowing, passaging would not save your cells.