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  • Jaker Hossain added an answer in Research Papers:
    When you have publihed first research paper in your life?

    i want to ask you at what age and designation you have published your life first research paper in conference. This question is very helpful to me for my research survey.

    Jaker Hossain · University of Rajshahi

    As M. Sc student age of 25

  • Can you suggest about the non-destructive testing equipment? Can you give me the list of all 'non-destructive testing m/c'?

    Hello everyone, I am trying to set up a "nondestructive testing lab" for casting metal. Please suggest any nondestructive testing equipment. If possible, then send me the supplier address.

    Thank You.

    Adin Stern · Ben-Gurion University of the Negev

    Aside from the aforementioned techniques mentioned by Prof Jose Ignacio Rojas Gregorio  from Catalonia, you may use a very useful link - see bellow: 


    also see a very good book by Charles J. Hellier

  • Is it possible to use kojic acid as targeting ligand for melanoma?

    is it possible kojic acid will target Melanoma????

  • Are there staining methods distinguishing bacteria, algae and fungi under high resolution microscopy?

    I want to count the number of bacteria, algae and fungi in water samples with a high-resolution microscopy in flow. I’m looking for (i) different staining methods that allow distinguishing all microorganisms (different fluorescences) and (ii) a method to conserve samples prior observations as well. What are the easiest and more efficient methods please?

    Mitja Remus-Emsermann · Agroscope, Wädenswil, Switzerland

    Hi Benjamin, the etoh fixation works very well for gram positive bacteria, but for gram negative bacteria it often just offers short term fixation. On some surfaces, i found that it still works very well but in solution one should expect rapid degradation of gram negative cell walls. To be on the save side processing the samples within a day should be OK but of course one can always test if the cells are more stable than expected. Problem is, if you would use paraformaldehyde fixation, which is really great for gram negative bags, gram positive one might be rendered impermeable to fish probes.

  • Harry ten Brink added an answer in Global Warming:
    Will recent warming hiatus with respect to mean temperature continue or not?

    2014 became the warmest year on record, without a strong El Niño. The so-called global warming hiatus (1998-2012) are widely concerned. In the following decade, global mean temperature warming will continue to slow down, or will rise much more rapidly than in the "slowdown" period? What are main physical causes responsible for inter-decadal changes of mean temperature?

    Harry ten Brink · Energy Research Centre of the Netherlands


    As for the conjunction of 2 planets

    Is this astronomy or astrology?

  • Bin Jiang added an answer in Marine Ecology:
    Any good book on GIS and RS application and practice for marine ecology?

    I need a "how to" book of Geographical Information Systems and Remote sensing, so that I am able to understand the principals and analysis of a procedure that can be applied the field of marine ecology specifically habitat modeling, migration pattern change, chlorophyll detection, change in the nutrient concentration, turbidity measurement etc.

    Bin Jiang · Högskolan i Gävle

    I believe the best how to books are software manuals, e.g., ArcGIS has a series of extensions such as spatial analyst, network analyst, track analyst, and each of the extensions has tutorial or manual. If you have encountered any questions or problems with the tutorials, go to some textbooks for answers.

  • Hari Mohan Pandey asked a question in Induction:
    How to implement context free grammar induction problem using PSO?

    please suggest reference and algorithm/code for PSO implementation for CFG induction

  • Krishnan Umachandran added an answer in Journalism:
    What is meaning of X in ISSN number?

    Some journals have ISSN number ending with X. What does it mean? Any insights?

    Krishnan Umachandran · Professor

    The xISSN Web service supplies ISSNs and other information associated with serial publications represented in WorldCat. Submit an ISSN to this service, and it returns a list of related ISSNs and selected metadata. The service is based on WorldCat, the world's largest network of library content and services. The current xISSN database covers 742,395 ISSNs.

    Ideal for Web-enabled search applications, such as library catalogs and OpenURL Resolvers, and based on associations made in the WorldCat database, xISSN enables an end user to link to information about alternate versions of serial publications.

  • What is mean by crystal structure?

    can anyone explain me what is lattice points and hkl notations in miller indices.

  • What is best for the university professor? Researcher only or teaching only, or a combination of both?

    In some of the countries of the world there is only one domain of either researcher or instructor?
    Does this affect the instructor's achievements in the field of scientific research?

    Sayed Zaheen Alam · University of Delhi

    Respected All

    Combination of both is a necessity for  knowledge generation, spread, dissemination correction, creation/shaping of future professors, realization of sense of duty and maintaining the Raison d'être of the academic disciplines with academic matter, professors/teachers, and its disciples or students.

    following wards may further assist: Mutualism, , shared, interaction, reciprocal, , reciprocatory, give-and-take, complementary.



  • Can anybody share the data migration application with implemented case study(tools used for it)?

    I have started with data migration literature survey, still I m unable get proper implemented case study which will explore the futuristic aspects of the data migration. In which application data migration needs more potential?

  • How can we assist in adaptation planning to sea level rise for the South Pacific Islands ?

    What knowledge can architecture, landscape architecture and planning bring to the sustainable development sciences in the field of International Development, specifically for the region of Australasia, and South Pacific Islands. Research and relevant papers that address this issue will be valuable in helping to frame and establish this research project. 

    Roohul Khan · King Khalid University

    Sea level rise is not a one time phenomenon it is continuos. Building floating structures will tackle any sea level rise in present and future. Venice is sruviving for so long why can't a floating city.

  • Mohammad Reza Ojaghian added an answer in Leaf:
    Can someone help me with the identification of this phenomena on Pecan leaf?

    It is around leaf with an extended part.

    Mohammad Reza Ojaghian · Zhejiang University

    Did you see this phenomenon on only one shoot or all leaves of tree?

  • Amin Nozari asked a question in Capacitor:
    Is there any capacitor that works with ultra-low voltage?

    I am looking for a capacitor that works in the voltage range of 50-200 mV. Could you please introduce me? What is the limitations of using these capacitors? How much would be the price?

  • Krishnan Umachandran added an answer in Attitude:
    'Attitude' or 'Motivation'? Which is a primary requirement for great achievement and why?

    There are some crucial aspects of our life that will determine whether or not we are successful in our endeavors. We may not be successful if we don't have those characteristics.

    In your opinion what is the major character trait which is required for achieving remarkable success, 'attitude' or 'motivation'.

    Thank you for your valuable opinion.

    Krishnan Umachandran · Professor

    Motivation is the driver for achievement.

    While Attitude aligns with motives, success is sure

  • Praveen Kumar asked a question in Charge Transport:
    In a metal-insulator system what is the mean distance between metal particles for percolation?

    i have a glass phase containing metal particles (ag) but the distance between these particles are greater than 15 nm. So is it possible that percolative charge transport flow through the glass layer.

  • Could anybody recommend a software/tool to analyse free-text data?

    I am looking for a software or tool to help me analyse free-text data from the survey. Any suggestions?

    Tatiana Chuzhekova · Saint Petersburg State University

    There is a list of such kind programs In Wikipedia. I hope it could be useful for you.

    Best wishes,


  • Nicole Albrecht added an answer in Eportfolios:
    Do you have experience using the current version of PebblePad software?

    Looking for usage particularly as a University student eportfolio tool. Also interested if you've experienced it within the context of integration with the Moodle LMS. Any strengths of the software; any weaknesses based on your experience?

    Nicole Albrecht · RMIT University

    Yes, are university trialled it. Students did not generally find it easy to use and after two years we discontinued use.


  • I have done LC-ESI-MS/MS of plant extracts. I have data about molecular weights product and fragments. Can anyone suggest interpretation?

    My software doesn't support unknown metabolite prediction I need some suggestion or source where I can convert the molecular weights (m/z) of parent and fragments into the suspected compounds. It will be greatly appreciated if someone can help to find the solution

    Muhammad Bilal Sadiq · Asian Institute of Technology

    Dear Mark, my method with instrument details is as follow, kindly if I could get any help will be a greatly appreciated

    Data acquisition and quantification were performed using Hystar 3.1 and Quantanalysis (Bruker Daltonics, USA). The compounds were analysed on Hypersil BDS  (150 mm x 4.6  mm I.D. 5mm) column protected by a Hypersil Gold    C18 guard column  (10 mm x 2.1 mm I.D. 5mm) using a gradient program in mobile phase containing 0.1 % FA in water  and 0.1 % FA in   at a flow rate of 400 mL/min. An Esquire 4000 ion trap mass spectrometer (Bruker Daltonics,  USA), with an Electro Spray Ionization source (ESI) interface operated in the negative ion mode, was used for LC-MS analysis. The ESI dry temperature was maintained at 365°C and dry gas 9 L/min. The ESI capillary is +3000 nA and the nebulizer at 40 psi. Quantification was performed using total  ion chromatograms (TIC) for the masss range 50-1000 m/z. Data were processed using DataAnalysis (Bruker Daltonics,  USA).

  • Md. Khalilur Rahman asked a question in Melanins:
    Do I need to keep the melanoma cell (B16F10) in starvation media before drug treatment for Melanin content assay ?

    I am planning to do melanin content assay using B16F10 cell line but I am not sure whether I put in starvation media before drug treatment .  

  • Mohsen Zommara added an answer in Lowry:
    Which is better in case of protein estimation (Lowry or bradford method)???

    Lowry or bradford???

    Mohsen Zommara · Kafrelsheikh University

    Lowry is Okay.


  • Can anyone suggest an economic health policy analysis framework?

    Hi I am doing my masters assignment in health policy analysis from an health economic perspective any suggestions on frameworks?


    Ralitsa Simeonova-Ganeva · Sofia University "St. Kliment Ohridski"

    There are many research directions in front of you.

    I had some experience in studying the impact of health policy on economic growth and I consider it rather interesting direction. You may check some of the following references:

    1. Barrо, R., “Health and Economic Growth”, Program on Public Policy and Health, Health and Human Development Division Pan American Health Organization, 1996
    2. Bhargava, A., Jamisson, D., Lau, L., Murray, Ch., “Modeling the Effects of Health on Economic Growth”, GPE Discussion Paper Series: No. 33, World Health Organization
    3. Bloom, D., Canning, D., Sevilla, J., ” The Effect of Health on Economic Growth: Theory and Evidence”, National Bureau of Economic Research Working Paper 8587, 2001
    4. Dormont, B., Oliveira Martins, J., Pelgrin, F., Suhrcke, M., “Health Expenditures, Longevity and Growth”, IX European Conference of the Fondazione RODOLFO DE BENEDETTI, 2007
    5. Fogel, R., “Economic Growth, Population Health and Physiology: The Bearing of Long-Тerm Processes on the Making of Economic Policy”, American Economic Review 84, 1994
    6. Howitt, P., ''Health, Human Capital, and Economic Growth: A Schumpeterian Perspective'', 2005
    7. Mexican Commission on Macroeconomics and Health, “Investing in Health for Economic Development”, Universidad de las Américas, Puebla, 2004
    8. World Health Organization, “Macroeconomics and Health: Investing in Health for Economic Development”, Report of the Commission on Macroeconomics and Health, Geneva, 2001
  • How can we increase the solubility of E. coli overexpressed protein?

    We are trying to purify an artificial protein. Very good expressed, but mostly in the spun down pellet. If anyone has experience to make it a bit more soluble, with a kind of mild buffer, additives, will be helpful. Thank you.

    Hsi-Ho Chiu · National Chiao Tung University

    If you find your protein in spin down pallet, two possibility you should consider. The protein formed a inclusion body or they was membrane protein actually. In my case, my protein was not soluble in quanidine or urea solution. However it was soluble in ionic detergent solution. Therefore I considered it was a membrane protein. Most answers mentioned above were suitable to inclusion body. For membrane protein, it was not easy to make it soluble in aqueous solution since it might have a hydrophobic out surface. If you forced it to become soluble in aqueous solution, it might changed its native folding. I have read some article mentioned about expression of membrane protein in lipsome, but I never tried before.  

  • Andrew Messing added an answer in Likert Scale:
    Can the dependent variable in multiple regression analysis be with only one question with different scale from independent variables?

    I have four IVs which measure by 5 point Likert scale.. The dependent variable is academic achievement which is student market (0-100). Is it any problem for multiple regression?

    Andrew Messing · Harvard University

    Technically there is always a problem using likert-type data/likert-scales for tests that assume normality: they can't be normally distributed as they don't even begin to approximate something that resembles continuity. The basis for transforming linguistic data into evenly spaced numerical values is shaky at best (and various studies have shown that response scales which better approximate a continuity or which use fuzzy set theory or other ways to correct for the baseless assumptions behind the Likert-type data transformations). The number of data points is quite low and multiple regression is sensitive to arbitrarily small departures from linearity, normality, and other issues that come up with likert-scales frequently because of the limited number of possible selections (which limits variance as defined by squared deviations, upon which all the standard statistical tests rely). But then, I'm not a fan of multiple regression either, so I'll pretend the two wrongs make a right.

    Plot your data. That's probably the most important step you can undertake especiallyin cases like this where responses will cluster (or spread) due to the extremely limited range of the IVs compared to the DV (the DV observations can range over from 0-100 while each IV observation has only 5 possible values). On the one hand, for every observation in an IV, one it's position in space prior to regression is determined by an quinary variable for one coordinate and 101 possible values for the other. On the other hand, depending upon the distribution of the DV observations, this can mean clustering rather than spread. Hence, plot your data (use multiple plots, graphs, whatever helps you "see" the relationship rather than just allow SPSS or some other package to spit out a number).

  • Justin Jesuraj added an answer in PEDOT:PSS:
    Ho do I prepare PEDOT:PSS substrate by diluting it down with IPA?

    I am making OPV devices with PEDOT:PSS as the hole conducting layer, what I originally did is to dilute the PEDOT:PSS solution (Al 4083) with Di-water at 1:1 and then spin coated the diluted PEDOT solution onto a hot substrate. I've recently seen a lot suggestions about diluting PEDOT with IPA, I want to ask the IPA:orginal PEDOTPSS solution ratio I should use, is it 1:5 or 5:1?

    why dilute it with IPA is considered better than with water?

    Another question: I don't have a ozone treatment or an oxygen plasma, and I just spin coat PEDOT onto a pre-baked ITO substrate (still hot during coating), and my PEDOT films seems well with no visible "dots", so my question is: are those equipment really necessary? and the PEDOT prepared after that treatment would be really better than from my "simply" method?

    Justin Jesuraj · Bharathidasan University

    I have experiences the similar situation while using PEDOT:PSS on ITO. But i overcome this only after the oxygen plasma treatment, i have also dilute it with water but obtained few dots along with smooth film, i have seen in a literature in which they suggested DMSO can act as better solvent for PEDOT:PSS compared to water or other alcoholic solvents. 

  • Can anyone list the factors that are responsible for material shortage in manufacturing industry?

    While manufacturing it may be possible that productivity may get affected due to shortage of raw material, I am interested in finding real life factors that are affecting productivity of manufacturing firm.

    S.M. Fijul Kabir Mahin · BGMEA University of Fashion and Technology

    The factores could be the followings

    1. improper costing

    2. wrong consumption calculation

    3. lack of desired quality

    4. defective or damaged raw materials

    5. improper coordination and planning during material transportation

    6. lack of proper inventory control

    7. over feeding to the machine may cause wastage of materials which results ultimately material shortage.

    8. faulty plant-layout

    9. improper materials handling within the plant

    10. excessive machine stoppage

    11. lack of sufficient auto stop motion

    12. faulty machine design

    13. improper production planning

    14. absence of sufficient production follow-up

    15. due to not maintaining 4Rs (right product, right quantity, right quality, right time,  )

  • If recent research demonstrates that synthetic statins pose higher risks than earlier reported, what are the best solutions for optimal health?

    A steady drumbeat of independent research demonstrates that serious risks and side/interaction effects from the most popular synthetic statin drugs is much higher than has been reported http://annals.org/article.aspx?articleid=1671715. Even the US Food & Drug Administration has expanded its advice and warnings to the public on this topic http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm293330.htm, as well as practitioners and health reporters http://healthimpactnews.com/2014/big-pharma-hiding-dangers-of-cholesterol-lowering-statin-drugs/. What are best ways to avoid the need for statins and realize optimal health that is not subject to these kinds of risks? 

    Max Stanley Chartrand · DigiCare Behavioral Research

    Yes, we haven't mentioned niacin nor COQ10, or even Red Yeast Rice, for that matter. And I am wondering about the possible implications on the newly discovered PQQ and its effects on hyperlipidemia. 

  • Yong Guk Kang asked a question in Fluorescence Imaging:
    Is there meaningful emission spectrum chage(shift) of VSD varying from kinds of solvent(EtOH vs DMSO)?

    Hi, I'm using Di-4-ANEPPS for voltage sensitive fluorescence imaging. 

    and based on my study,
    I began to doubt that some spectral shifts were occur by change of solvents. 

    But I cannot find any quantitative information about shifting of spectrum based on solvents.

    Is there any kind of articles that has information about emission spectrum chage(shift) of VSD varying from kinds of solvent(EtOH vs DMSO)?

  • Which analytical framework is suitable for the study of school-based in-service education and training?

    I am writing a research paper on the implementation of school-based professional development in my country. For quite a time I have struggled with developing the right theoretical framework to analyse the construct "continuous professional development:. I cant figure whether PD is a process, activity, a goal or an outcome. I was considering "socio-cultural perspective", "situated perspective" and "activity theory", they are  so confusing. Should I pick one of these or find something else? Which would be more applicable? Please advise.

    Simbarashe Munikwa · Chinhoyi University of Technology

    Where can I access literature on paragmatism as a guiding philosophy for mixed methods research approach ?