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  • Ihsan Ates added an answer in Contrast Agents:
    Is there any effective profilactic teatment before the IV contrast substance?

    Is there any effective profilactic teatment before the IV contrast substance? 

    Ihsan Ates

    Thank yok Dear Sameh

  • Mushtaq Ahmad added an answer in Fish Diseases:
    Is Penicillin useful in the cure of fish diseases?

    Penicillin is an antibiotic and useful in many diseases.

    Mushtaq Ahmad

    The penicillins, including penicillin, amoxicillin, and ampicillin, are most effective against gram-positive bacteria such as Streptococcusspecies; therefore, for the same reasons as those given above, these antibiotics are not a good first choice for most bacterial infections in fish. None of the penicillins are FDA-approved for use in food fish.

    Use of Antibiotics in Ornamental Fish Aquaculture

    details in;


  • Patrick Solé added an answer in Graphs:
    Is it appropriate to change constant notations in graph theory?

    Since i have notational conflict, i would like to use another notation of the graph K4-e, for example K4-\acute{e}. Is it appropriate? thank you for answering my question.

    Patrick Solé

    @Peter: yes and there might even be loops in that graph!

  • Mohammad Reza Azadehfar added an answer in Performing Arts:
    What are the disadvantages of using western music notation to transcribe indigenous non-western ethnic music and what can be used as an alternative?

    Western music notation used widely in transcribing and notating non-western music. Well, it looks a media beside the oral transmission of music which can help grasping structure of a certain type of music, but it is not. Western music notation forces its limitations in transcriptions and through the history the notated version remains as the document or “original version” against changes take place in oral versions over time. It is in spite of modifications the written version already got through transcribing musical sound to written notation.

    Mohammad Reza Azadehfar

    I very much liked the expression of Nuno “adapting the notation to the music instead of the music to the notation.” In some of my books and articles I developed some new symbols and techniques and I always had to have a side notes explaining what they mean. I am also thinking of establishing a study group in our ICTM (International Council for Traditional Music), to gradually extend and standardize new symbols. I am thinking that this solution might also have some disadvantages that I might not be aware of. Please let me know anything coming to your mind my friends.

  • Hubert Branger added an answer in Density:
    How is possible to use PIV for a fluid flow initially perfectly ate rest?

    I need to use planar PIV for detecting the instability cells in a Hele-Shaw cell triggered by a gradient of temperature, with a window size of 40x40 mm^2. The fluid in the cell (1 or 2-mm gap) is initially perfectly at rest, then increasing the vertical gradient of temperature instabilities develop at a given critical Rayleigh number. I need small particles (tens of micrometer in diameter) which do not settle or float for, say at least 10 minutes, to act as tracer. Probably some natural substance, able to absorb water and to equalize its density with the density of the ambient fluid, could represent a good solution. Does anybody have experience on the topic, in order to give me hints and suggestion?

    Hubert Branger

    Hello Sandro,

    This is a so difficult and unsolved problem ! i had always problems of non 1000 kg/m3 densities. Sure Pine pollen would be good choice, but i thought that pine pollen particle diameter was greater than 30 microns, very often near 50 micron. . May be now companies propose now smaller pine pollen particles ? The lighest polyamide particle are now 1030 kg/m3: which is 3% too high (not 5%) .  see:  http://www.dantecdynamics.com/seeding-materials    . But i guess that 3 % is also too much: you need no more that 1/1000.



  • Issam Rezaiguia added an answer in Fluid Mechanics:
    What is the relation between velocity and shear stress distributions for two immscible fluids flowing?
    Please check out this: Two immiscible liquids A and B are flowing in laminar flow between two parallel plates. Would there be a possibility for the velocity profiles to take this form below?
    Issam Rezaiguia

    thanks doctor Brian 

    I mean that each layer have different pressure gradient

  • Elaheh Azizian Farsani added an answer in Abaqus:
    Which subroutin should i choose in abaqus software for low-cycle fatigue?


    I want to model low-cycle tension-compression fatigue of a cylindrical model in abaqus with thermal conditions. I need a tutorial for writing subroutin for this example.

    which subroutin should i choose for that?

    Thank you

    Elaheh Azizian Farsani

    Hi dear Dr. Yasseri

    Thank you for your answer and the information you had sent me.

    sure i will use them for my work.

    i understood that i need to write UAMP subroutin to define a load amplitude for fatigue load.

    but maybe there is a way for define an amplitude without writing subroutin.

    anyway i don't know about both methods.

    could you please help me that how can i define amplitud  without subroutin?

  • Sylwia Mrozowska added an answer in Energy Policy:
    Currently, we observe an increase in global challenges for energy markets. What do you think about The European Union energy policy?

    Currently, we observe an increase in global challenges for energy markets. The European Union is of the opinion that the only way to deal with these challenges is more Europeanized energy policy. For many people the problem of global warming is a political issue and not an economic or ecological one. Moreover, in this sphere, we deal with numerous myths, stereotypes, conflicting views, distortions and accuasations. What do you think about The European Union energy policy?

    Sylwia Mrozowska

    Dear Lucio,

    Thank you very much for your answer. I will read your paper Understanding the Road Towards... and will write you comment. Best.

  • Alan Robinson added an answer in Optisystem:
    Improving the eye diagrams of a TDM pon?

    How could you improve the Q-factor and hence the eye diagram of a PON that uses Time Division Multiplexing? I have simulated one using Optisystem but the eye diagrams are too bad. How could i improve this? Regards

    Alan Robinson

    Just to clarify are you using a "tree" distribution system, similar to EPON or GPON, or some other architecture with a single CW laser and multiple MZ modulators?

    What is your sample rate?  Is it the same as your symbol rate (7 G Bd), or faster?

    Is the poor eye at the ONU (subscriber) terminal, at the OLT (head end or central office) or both.  Alternatively, is your architecture more nearly a peer-to-peer scheme?

  • Beata Stępień added an answer in CASINO:
    Kung Hei Fat Choi! Are you, your country, town or community celebrating the New Chinese Lunar Year of the Fire Monkey?

    In 2007, we have started an ongoing research project on “Globalization of Holidays and the Calendar”. In the beginning, we were only interested in trying to understand the rapid spread of holidays that, as Halloween and St. Valentine, didn’t have any cultural tradition in Chinese communities but became an important economic asset as well as festivals mobilizing casinos, hotels, restaurants, then schools and associations, nowadays firmly installed in social networks exchanges. Thereafter, we have also started studying the diffusion of public and private festivities of the New Lunar Chinese Year along with the growing economic presence of China worldwide. We have been systematically inviting Master and PhD students to research the topic and I would like to appeal to your collaboration. Can you give us information, pictures, videos or any other documents regarding the diverse celebrations of the Chinese New Year in our country, town or local communities? If there aren’t any commemorations at all, can you explain the situation? What do you think about this clear globalization, industrialization and marketization of holidays that, in some cases relatively new, are being celebrated among other cultures and communities? Is there a main economic driven factor or there also are much more complex cultural and social elements?

    Beata Stępień


    we do not celebrate any Chinese festivals, feasts etc. in Poland.  Probably the reason is, that the Chinese minority is tiny here.and China is both physically and culturally distant from Poland....

    We have a lot of Chinese horoscopes in magazines in January, but apart from this, i don't  think that average Polish is even aware of the fact, that the New Chinese Year is coming.

  • Preetam Nath asked a question in Physical Exercise:
    What should be the ideal method for measuring intensity and total calorie of physical activity?

    There is an endless list of studies on effect on physical exercise on metabolic disorders like NAFLD. Most have used self reported questionnaires especially in retrospective studies which have an inherent recall bias. What should be used for a prospective study in this field? Pedometers or accelerometers or any other instrument? 

  • Keerthy Vijayan asked a question in DNA Polymerase:
    What is the reason for Primer Dimer formation in a PCR reaction? What is the role of PCR reagents in Primer Dimer formation?

    Again while doing the PCR amplification of snail DNA, I got stuck with no visible bands on gel. But there is the presence of primer dimers in the gel. The DNA pellet I got readily dissolved in double distilled water and it is about 100ng/ul in quantity. I had added about 8ul of DNA templte to 50ul reaction mixture. What could be the possible reason of no band formation? Is it due to more amount of template DNA? or due to any of the PCR components? Does Primer Dimer formation is due to defective PCR reagents?

    But primer dimers are seen on every gel.

    Please help.

  • Daniele Sasso added an answer in Mass:
    If a non zero rest mass object is moved at speed of light how much its mass should be appeared?

    I know most of the answers will say infinity, but still this needs deeper look about its physical meaning and does it consider a practical logic?

    Infinity usually used for something we could not measure, however the reality may be different!

    Daniele Sasso

    In fact, I agree. In this situation total energy is null.

  • Yuan-Yeu Yau added an answer in Conventional Breeding:
    Why molecular approach takes more time to develop a new crop variety than conventional breeding?

    From the literature it appears that molecular techniques take much more time to develop a new crop variety.

    Yuan-Yeu Yau

    @  Md. Abul Kalam Azad: 

    "Why molecular approach takes more time to develop a new crop variety than conventional breeding?"

    Sometimes, it also takes so long to 'de-regulate' a GM crop. See the recent article from TheScientist Magazine. See the yellow highlighted part. The example used in the article, it took nearly 10 years to de-regulate the GM apple.

  • Rocco Cavaleri added an answer in Statistical Software:
    Which statistical softwares is suitable and easy to use?

    Among the statistical tools:  Origin Lab, SPSS, sigma plot and R, which one is reliable and easy to operate for biological related experimental analysis?

    Thank you,

    Rocco Cavaleri
    The only problem with R is that it can be a bit tricky. SPSS, I find, is relatively straightforward.
  • Mazhar Hussain added an answer in Splicing:
    How to find out the the duplicated sequence in the database?

    Hi everyone,

    I'm currently working on the splicing variants of a protein. For the analysis, I extracted variants from two databases in Fasta format.  Before downstream processing, I want to make sure that no variant is repeated. So, how can I check this? I m using standalone BLAST on Linux.  I tried using MegaBlast, but I'm not very confident about the results... in results e value is mostly zero and show 100 percent identity among sequences, bit score goes very high sometimes... the only thing which differ is query coverage... the start as well as end sites position vary in query and database sequence... I had to ask u... in the splice variant case can I make the query start and end difference as the basis of the difference of splice variants. I shall be waiting for ur response.

    Mazhar Hussain

    Mazhar Hussain

    Thank you everyone for your response... Since this last week, I am trying various different options and some of them have potential to get me unique hits. But as Brian mentioned, uniqueness could be at exon-intron structural level or SNPs. In my case, I want to ignore the SNPs and just go for Splice variants. And I tried Multiple sequence alignments to find out the unique patterns but the task seemed too big for the manual execution and MSA becomes really challenging when you have a lot of alternatively spliced products of all sort of sizes. In this case, it will generate unnecessary gaps or misalign the sequences.

    So, kindly let me know what kind of tools or BLAST settings I shall use to get the results.


  • Hazim Hashim Tahir added an answer in Political Socialization:
    Who is a sycophant? Is sycophancy an Art?

    We see sycophants in all the fields - political, social, administrative ......

    Do you think it is an art that is harmless or something that harms the organisational culture severely.   

    What kind of sycophants are prevalent in your part of the world.

    Hazim Hashim Tahir

    Dear Colleagues,

    Good Day,

    Please, see where a person learns "Sycophant"

  • Nikolaos Pellas added an answer in Emotional Learning:
    What is the role of emotions on online learning? and which type of emotions has the highest influence on the online learning outcome?

    what is the affect of different emotions that learner experience during online learning task, and which type of emotions that enhance the learning process outcome? 

    Nikolaos Pellas

    Hello Atef 

    Please read some of my articles that you can find in my profile. I would recommend the following:

    1. Pellas, N. (2014). The influence of computer self-efficacy, metacognitive self-regulation and self-esteem on student engagement in online learning programs: Evidence from the virtual world of Second Life. Computers in Human Behavior, 35(1), 157-170.

    2. Pellas, N. & Kazanidis, I. (2014). Online and hybrid university-level courses with the utilization of Second Life: Investigating the factors that predict student choice in Second Life supported online and hybrid university-level courses. Computers in Human Behavior, 40(2), 31-43.

     Kind regards


  • John Macken asked a question in Quantum Mechanics:
    Are there any of the mysteries of physics that are beyond our intellectual capacity to conceptually understand?

    Richard Feynman said, "If you think you understand quantum mechanics, you don't understand quantum mechanics.” Is the problem that the human intellect is incapable of understanding some aspects of quantum mechanics or are we merely missing a model which will make the mysteries of quantum mechanics conceptually understandable? Another quote attributed to Feynman is “Shut-up and calculate”. This implies that a student is being told to suppress their natural desire for conceptual understanding and instead work on mathematical analysis. Do you feel that some questions are beyond our intellectual capacity to successfully answer? If so, perhaps you should identify these to stimulate discussion. For example, questions about the composition of fundamental particles or string theory strings are often treated as unanswerable. What are your thoughts?

  • Jasmin Ćosić added an answer in Steganalysis:
    What are the free open source steganalysis tools?

    Please share the software/ Code/ Link for steganalysis techniques.

  • Rami Vitale added an answer in Newtonian Mechanics:
    How was the Newtonian mercury perihelion precession calculated?

    The additional perihelion precession of Mercury's orbit was considered the first confirmation of General Relativity theory. It is mainly the difference between observational data and Gravitational tugs of the other planets on mercury's orbit upon Newtonian mechanics.

    My question is how was the Newtonian effect calculated and how much are the methods used trustworthy.

    Rami Vitale

    @Kåre I have read all the answers and the link you provided led me to the same conclusion. Nevertheless, I am not obliged to reply to answers not related to the subject

  • Nikos Lagaros added an answer in Meta-Heuristic Algorithms:
    Can anyone help me?How can I encode solutions in reliability optimization problems?


    I'm new in reliability optimization problems topic. I want to solve these problems with meta-heuristic algorithms. How can I encode solutions for generating initial population?

    Nikos Lagaros

    Use latin hypercube sampling for generating the initial population.

  • Peter J Mponzi asked a question in Beds:
    What could be the diameter and length of the trickle bed reactor if production capacity is 20000L/day (13,8L/min)?

    Dear Members,

    What could be the diameter and length of the trickle bed reactor if production capacity is 20000L/day (13,8L/min)?  Does anyone have a knowledge of how to calculate those two parameter? Please let’s presume that the trickle bed reactor are in the form of cylindrical shape. Thank you.

  • Parida Aditya added an answer in Maintenance Management:
    Anyone know how to document a "Good maintenance practice"? Is there a manual that can be used as a guide?

    I need to document in a quality management system, the performance of good practice in a maintenance department.

    Parida Aditya

    Dear Michael,  Maintenance is a multi-disciplinary area involving many stake holders' conflicting interests. It has become more complex with continuous technological development and changes, especially in the area of diagnostics and prognostics for a real time monitoring, control and decision making under a very competitive dynamic business scenarios. There are few books on maintenance best practices, but what you are asking is the maintenance manuals which the organization prepare for undertaking maintenance activities. What is good for an organization will not be good for another as each organization is unique and different. One need to follow the best practices and maintenance manuals from some of the successful organization and develop your own manuals. One good document to follow for the maintenance manual will be ISO 55000-Asset Management.   

  • Alan Robinson added an answer in Filters:
    Can anyone help me to choose the optical filter?

    What material can be used to filter based on the intensity of laser beam
    Not wavelength

    Alan Robinson

    A saturable absorber will attenuate more strongly at energies below saturation, and transmit higher energies.


  • Ramanujam Gs asked a question in Inventory:
    Major bottle necks for an IOT/ M2M: and few quick solutions , kindly suggest if these are correct, if not what are the challenges ?

    Major bottle necks for an IOT/ M2M:

    Service provider service / Connectivity at all the places.
    Cost of the M2M platform/Infrastructure.
    Lack of machine learning skills and Accurate Predictive analysis decisions.

    Solution to address one of the issues (Cost of M2M platform /Infrastructure):

    Usage of the existing Telecom COTS (B/OSS) products.
    Effort spent on testing the new requirements is less, since these products are present in the market from a long time.
    Customization is easy since we have skilled resources existing in the respective field.
    Bringing Trust and confidence to the customer is easy.
    Revenue is targeted to the service integrators (GMT) than the Product owners.


    Good amount of effort is spent on building Adaptors for M2M Platform.

    Adaptors: Convert the various data format sent by the machine to platform in understandable format.

    And also add values to few columns based on the existing data.

    All of this can be handled by any of the standard  COTS Mediation system .Currently Mediation system is currently doing similar functions to convert the data from various  switches in understand able formats to various down streams systems like FMS , Billing , data ware house etc.

    Billing Platform: The existing Billing platform can used to bill based on the usage rather than current flat billing in M2M space. This provides to Bill Accurately and transparently.

    With minimal changes to the mediation system all the M2M CDR can be stamped / identified, and Billing system can apply various rate plans, based on the Application and the Market trends.

    Provisioning system can used for the as a Work flow engine.

    For tracking the activities from Order to cash 

    Pre-casting the device with the Sim
    Activation of the Sim with various set of pre-conditions based on the Machine and the application, including the TRAI formalities of getting the CAF approval.

    Inventory system: Can be used not only for the Number IMSI inventory but can also be used for the Various M2M device inventory with tags to various M2M applications.

     This can be used only where device / Machine has the capability to fetch required data.
    The analytics (Predictive analysis decisions) logic has to build as a separate system.
    This cannot be used where machine cannot fetch the required data that is in Pull cases.

    Idea Born: when we spoke to one small M2M Vendor for white labeling some of the features of his M2M platform, the most expensive feature of his platform was of the Adaptor .

  • Ponkumar Ilango added an answer in Civil Engineering:
    Whether the sulphur free lignin can be used for clay soil stabilisation?

    civil engineers

    Ponkumar Ilango

    Dear Jayashree Jayakumar,

    Biochar is to increase the fertility of the soils to get agriculture Productivity,This can be used.

    But In Soil load Bearing Capacity will not increase .

    Is lignin a waste product from paper manufacturing industry? Can it be used for soil stabilization? - ResearchGate. Available from: https://www.researchgate.net/post/Is_lignin_a_waste_product_from_paper_manufacturing_industry_Can_it_be_used_for_soil_stabilization [accessed Feb 7, 2016].

  • Sergei A. Ostroumov added an answer in Drinking Water:
    Is it really necessary to add chlorine to drinking water before it is delivered via tubes to people?

    On one hand, it is necessary to prevent bacterial contmination. On the other hand, there is a hazard of toxic effects of chlorine...

    Sergei A. Ostroumov

    Dear Bachir, 

    Dear Henrik,

    thank you for your contribution. The issue is not simple. I do not think it is easy to find a best solution. However we have to work on it. May I vote your answers up.

  • Elena Cocorada added an answer in Attitude Change:
    Does anyone know academic papers on learning about oneself?

    Dear colleagues
    Does anyone know articles / academic papers on learning about oneself?

    Academic learning is analyzed frequently focused on knowledge about the external world. Simultaneously, it practiced personal development. Also, psychological therapy facilitates learning about their own values, behaviors, attitudes and their changing. Does anyone know academic papers showing this process from the perspective of factors, conditions or mechanisms of this type of learning (learning about oneself)?

    Thank for your help!

    Elena Cocorada

    Dear Mustafa Tekke, 

    Dear Hendrika Vande Kemp,

    Thank you for suggestions and promptitude of response. I have already requested items which are not available ResearchGate.


  • Pn Haray added an answer in Lung:
    Is there a role for pallaitive APER in patient with lung mets?

    48 yrs old gentleman diagnosed with low rectal tumor with threatened CRM with lung mets - resectable

    post long course CT RT  - primary responded but lung mets now inoperable

    underwent 3 months of palliative CT - excellent response to lung mets now multiple seen but all between 2 - 8 mm 

    pt has no symptoms from rectal tumor - what is role for palliative resection?

    Pn Haray

    Hi Parin,  In the presence of unresectable metastases, surgery for the primary (in this case APER) should be undertaken only in exceptional circumstances. 

    • If the patient has significant symptoms with bleeding/ incomplete evacuation/ pain/ severe diarrhoea etc. then a palliative resection is justifiable. 
    • If only obstructive symptoms, then a palliative resection would not be justifiable (in my opinion) and the options would be a
    • If the patient is relatively asymptomatic, then palliative surgery would not be appropriate as, even if he's fit, he will take several weeks to recover (even if no morbidity/ mortality), during which time, his palliative chemotherapy will be delayed. Also, as he appears to have had radiotherapy already, the chances of delayed perineal wound healing are high and may delay chemo even further.

    In summary, therefore, in my opinion, the role of palliative surgery in the presence of inoperable mets is restricted to symptoms that cannot be palliated by stoma/ stent.  If the patient is relatively asymptomatic, may be a good option to encourage him to enjoy the rest of his life rather than reduce the quality with side effects from Chemo.  The proposed study mentioned by Avanish Saklani may provide  some answers tho this question, in due time.