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  • Nadir Demirel added an answer in Organic Acids:
    How to obtain and isolate free amino acids methyl esters from their hydrochloride salts?

    These esters are needed in the free form to prepare salts of organic acids where esters will be act as cationic component.

    Nadir Demirel

    To a solution of amino acid methyl ester  Hydrochloride in Hexane (100 ml), excess morpholine was added. The mixture was stirred at room temperature for 15 minutes. The mixture was heated to 60oC and the resulting solution was filtered and crystalized from hexane to give white solid.

    second Method

    To a solution amino acid methyl ester Hydrochloride in CH3Cl (50 ml), 50 ml concentrated K2CO3 solution was added at 0oC.  The H2O phase was extracted three times with the 50 ml CH3Cl. The organic phase was combined dried over Na2SO4 and evaporated. The solid recrystallized from hexane to give white solid.

  • Ian Kennedy added an answer in Manufacturing Systems:
    How a perturbation can be identified during the manufacturing scheduling process ?

    I would like to know, the practical automated tools or approaches used to identify the presence of  disturbances (machine breakdown, late arrival of tasks ....) during the manufacturing process ? 

    Thank you.

    Ian Kennedy

    A monitoring of statistics is a useful approach. When the average service time at a station drops below 10% of its norm, you know you are in trouble! This stat do not tell you why. You need to look at the big picture of all stats to work out why.

  • C.J. Stigter added an answer in Agricultural Development:
    May I ask for some references related with national cotton promotion policies in Pakistan?

    I am doing policy analysis of cotton production policies in Pakistan. Most of the documents refer to textile policies. It will be great if somebody can refer some review articles or government policy documents. I want to eventually take it to sustainable cotton production. 

    C.J. Stigter

    Dear Farhad,

    you may also like to see


    Regards, Kees

  • Srinivas H Gowda added an answer in Animal Cell Culture:
    What is the ideal co2 concentration to be maintained for animal cell culture (adherent cells) in hypoxia (0.2% Oxygen )

    cancer cell lines

    Srinivas H Gowda

    dmem high gulcose

  • Reinhard Stindl added an answer in Social Networks:
    Do scientists tend to gain preferably informations which confirm their opinion and fade out contradictory statements?

    I heard (Süddeutsche Zeitung, February 6/7th 2016), that people like to sit in a "reverberation chamber", they are consuming only informations which confirm their opinions, because it feels good to be liked or confirmed.

    The social networks tend to strenghten this behavior, especially with the help of new filter systems, which gain new connections by evaluating the personal data of the user.

    Is this contradictory to objective thinking and having an open mind?

    What about the filtering systems of RG?

    Reinhard Stindl


    Peer review is useless when it comes to the introduction of new concepts in biology. Average scientists will always adhere to the mainstream view and defend it. Even worse, peer review and the global "publish or perish" trend have severely damaged modern science. About half of the published literature (in peer reviewed journals) may simply be untrue. 

    Recent article of the editor-in-chief of the Lancet

  • Gregorio Castejón Porcel asked a question in Auctions:
    Do you know any place where the water auction is used as traditional system of sale and distribution of this resource?

    I know several places where since centuries the water auction is used as sale system and want to find other regions in the world where is used this sale system. Thank you. 

  • Peder Wolkoff added an answer in Indoor Air Quality:
    Is there any correlation between indoor air quality and the happiness of building occupants?


    Does anyone know if there is any explicit correlation between indoor air quality and the happiness of building occupants? Could you provide some references?

    Many thanks, Ana

    Peder Wolkoff

    Dear Ana,

    i just came across this one that appears to be quite relevant for you.

    Cent Eur J Public Health. 2015 Dec;23(4):314-20.
    Housing Satisfaction in Finland with Regard to Area, Dwelling Type and Tenure Status.
    Pekkonen M1, Haverinen-Shaughnessy U.

    Best regards,


  • Eric Faÿ added an answer in Morale:
    Are ethics a grammar of human expression or an essence of human relation?

    Are ethics relationally bound, universal, or ethically relative? 

    Who decides whether something is right or wrong?

    What is the syntax of the governing certainty about the implausibility of one representational ethos over another?

    How do we conceptually calibrate the reorganization of society ethically, if we do not have answers on basic morality?

    What institutions recondition our moral compass when we have through the agency of our own moral experiments fail?  Do these institutional roles succeed because of our reforming our behaviours, or through our being coerced into submission?

    Is there a time for force if so who decides how much force is appropriate?

    Eric Faÿ

    Dear Peter,

    I will follow French Philosopher Michel Henry's to suggest that ethics is part of the essence of human life.

    The core argumentative line is the following:

    1) they are two ways of appearing (which is the question of phenomenology): in the light of the world, at a distance... in the light of affect, with no distance, which is according to Henry the light of life.

    2) Hence the ontological statement of a divided subjectivity:  identity appears in the light of the world when ipseity appears in the light of auto-affection feeling oneself (see Henry's Genealogy of psychoanalysis which discusses Descartes' cogito ergo sum). Ipseity as singular life is given to itself from Life. From there the ontological self is both affective self and "I can", active self (see Henry's Phenomenology of the body) and the source of practice as experienced by the affective self.

    3) Hence praxis may be deployed by according to the prescription of life to life itself as a good life with and for others (which is Paul Ricoeor's defintion of ethics). Non ethic behaviour occurs when precritions, let's say objectives, ways of doing comes from light of the world disconnected from light of life (i.e. making profit at any cost. Just to remember that Lockes political ideal was to favour anyone life). Which means that malaise, the experience of acting against one's life prescriptions is silenced.

    4) Culture (what you call grammar ?) as opposed to Barbary (see Henry's book  Barbary) appears as the way from generation to generation are transmitted ways of life which help one's life growing with and for others. Which presupposes one's life desire to grow, to live itself at the utmost. Barbary hence may be understood as perverted culture where acting, disconnected from its ontological source (i.e. following the mathematical principle of maximisation) is institutionalised.

    Hope you'll find this usefull. Some expanded views are in the following paper available in RG: Perezts, M., Faÿ, E., Picard, S., (2015), “ Ethics, Embodied Life and Esprit de Corps, an ethnographic study with anti-money laundering analysts”, Organization, 22(2): 217-234. 

    Best wishes,

    Eric Faÿ

  • Idris Aida added an answer in Social Entrepreneurship:
    Has somebody worked on related topics like motivations of social entrepreneurs creating social enterprises?

    I'd love to share insights about social entrepreneurship, motivations regarding new venture creation, related literature, common methods, empirical data and analysis. 

    Idris Aida

    Hi Duyen,

    As you well know, context is very important in social entrepreneurship (SE) research.  In my study of SE development in Indonesia, it was discovered that religion is one of the key factors motivating SE among the locals.

    For a more detailed discussion, please refer to:

    Idris, A. and Hijrah-Hati, S.R. (2013).  Social entrepreneurship in Indonesia: Lessons from the past.  Journal of Social Entrepreneurship 4(3), 277-301. 

    Best wishes,


  • Christian Q. Scheckhuber added an answer in Protein Markers:
    Can anyone recommend a protein marker/markers of oxidative stress to be analyzed by RT-qPCR?

    I am trying to analzed by RT-qPCR the noise-induced oxidative stress in cochlear cells.

    Christian Q. Scheckhuber

    You could consider components of the antioxidant defense system: catalase, superoxide dismutase, glutathion peroxidase, glutathion reductase, thioredoxin, peroxiredoxin, etc.

    Cheers, Christian

  • Aboud AlJa'bari asked a question in Nitrous Oxide:
    Nitrous oxide, does it still exist!?

    When i was a resident, i always use nitrous oxide along with oxygen unless contraindicated,in the recent few years, i completely stopped using it. What about you,do you still use it and is it still beneficial? 

  • Shiuh-Hwa Shyu added an answer in Vortex:
    How will be the vortex generated by the back of an axial impeller blade that pushes the fluid upward?

    I found the vortex type generated by pitched blade or hydrofoils agitators but all the times there are oriented to push the fluid down and in clockwise flow. But if i have a blade that is oriented to push the fluid up i am not able to guess if the vortex will be oriented upwards or how. I attach a view of my complex agitator and i am talking about the vortex created by the outer blades. Thanks in advance!

    Shiuh-Hwa Shyu

    If the propeller rotate clockwise looking from top to down, the flow to the inner bade looks like --> \ , while it is --> / for the outer blade. The vortex will generate on the back side of blade, so the inner blade vortex rotate clockwise pointing toward the vertical axis (downwash) while the outer blade vortex rotate anti-clockwise pointing away vertical axis (upwash). That's why we see the fluid near the vertical axis flowing downward. 

  • Rahul Kapadia asked a question in Graphene Oxide:
    Is there any computational simulation software available to simulate Graphene oxide or Graphene?

    Simulation software which can simulate quantity of different Graphene oxide materials and gives best solutions.

  • Nicolas Lebon added an answer in Fractals:
    What are the equivalent roughness parameters for the contact between two surfaces ?


    I have to model the contact between two surfaces. To do that, I use a constitutive contact model, in which I need the 3 roughness parameters Rq (RMS rugosity), etha (number of asperities /m²) and R (asperity radius). 

    The problem is : I know how to obtain these values with 3D surfaces measurements with PSD or fractal means, but for ONE surface. When I have to study a contact, I have TWO, so I need some equivalent properties to put in the model.

    From what I read, it seems I have to take Rq,eq = Rq,1+Rq,2, 1/R,eq=1/R,1+1/R,2 and for etha I don't know...

    I am not sure about these relationships and I don't know if they are always true.

    Does anybody have some clue ?

    Thanks a lot


    Nicolas Lebon


    La formule ressemble beaucoup au calcul de résistance équivalente en électronique!!

    Le paramètre R ne semble pas être un paramètre normalisé de rugosité.

    Etant donné qu'il s'agit de surface je me serais orienté vers des critères de rugosité 3D genre Sa ou Sq ou Sz Spk....

    En réalité pour choisir le bon critère de rugosité, il faut connaitre le but de cette modélisation? le contact est modélisé pour étudier l'usure, le frottement, ou l’étanchéité?

  • Jay Prakash Singh added an answer in Nonlinear Systems:
    What are the elements used to characterize transient chaos?? About the finte-time Lyapunov exponent can you please help me with its definition??

    Hi I have a system which seems to present transient chaos and I am beginner in this domain. Please what are the elements used to characterize transient chaos in a system?? About the finte-time Lyapunov exponent can you please help me with its definition??

    The time evolution I have is shown by the figure attached.

    Thank you for your answers


    Jay Prakash Singh
    You can refer paper attached here.
  • Kashmiri Deka added an answer in DSC:
    Is there any explanation to non-dependency of fractional conversion of thermal reaction on heating rates?

    Generally, if we perform thermal decomposition reaction of a material with different heating rates, fractional conversion curves for different heating rates shift towards right with increase of heating rate. But when I perform thermal decomposition of cellulose with different heating rates, it does not follow the above rule. Can anyone provide me with any explanation to it?

    Kashmiri Deka

    It was DSC analysis. It is a multi stage decomposition reaction and we considered the peak at near 350oC for calculation of fractional conversion from different heating rates. The exact peak positions were 363.0, 367.8, 369.1, 343.9 for heating rates 8oC/min,  10oC/min, 12oC/min, 14oC/min respectively. The fractional conversion values were calculated based on the areas covered by the peak.3

  • Vilemar Magalhaes added an answer in Chinese:
    Why the new year is different in different nations and countries?

    The Chinese new year does not coincide with English, while the Bengali new year (Paila Baisakh) is another date. Why this discrepancy?

    Vilemar Magalhaes

    Yes Dear Maria,

    Not even repeated words have the same meanings. This is why it is so fun to interact with other cultures and people. I would like to see those trash food suppliers disappearing, each one in its own way.

  • Deidré Kleynhans asked a question in Plagiarism:
    Self-Plagiarism and referencing your own work?

    Good day Researchers!!!

    I am very new to research so I have a lot of rookie questions that I hope someone can assist me with.

    I have a question regarding referencing your own work?

    I would like to know if I have done a research proposal as part of my Bachelors degree can I use the same proposal for your Masters and build on that knowledge? Will i plagiarize by using my work work? The research proposal (the literature review, research problem , design etc ) will stay the same , will this be accepted or do I need to start again for the Masters degree?

  • Maria Fanto added an answer in Acetonitriles:
    Is there any way to measure the pH of an acidified Acetonitrile solution?

    I wanna do some pH dependence study of absorption and fluorescence spectra.

    Maria Fanto

    :) Then we understand each other

  • John Clarkson asked a question in Gaussian:
    Anharmonic Raman Intensities in Gaussian 09W Revision A.02?

    I wish to compute anharmonic Raman intensities in Gaussian 09W Revision A.02. I have computed the anharmonic IR frequencies which can be found in the output file.

    How do I set up the input file to compute the Raman intensities using the anharmonic frequencies and force constants found in the checkpoint file? (I think I have to use Polar =Raman?)

    Can anyone help with the Gaussian input file script to allow this? Would be much appreciated!

  • Thomas Heise added an answer in Rock Art:
    How does the study of rock art and archaeology make a difference?

    Are these studies relevant?  Can they contribute anything to our contemporary industrial society?  What types of people would see our academic and conservation efforts to be of value?

    Thomas Heise

    Dear Bryan and James, yes it is completely true, the shapes and natural forms of rocks have been often used in the minuscule as well as in greater dimensions to produce the feeling and meaning they wanted to give and Show. This has been used inside the Caves, but also outside like in Africa and Tasmania.

    But light was also used not only by the torch but as well by the sunbeams entering the Caves at specific Dates like the equinox and pointing thus in Lascaux to animals which have been recognized as the starcalendar / zodiac from that time by now. Another aspect is the Position in regard to the sounds/echoes and their Vibration which is very Special at or just near the place of paintings.

  • Michaël Tatham added an answer in Public Policy:
    Can paradiplomacy be a type of public policy?

    Is there any author that I can use to support the assertion that paradiplomacy (the foreign activities of subnational political entities, such as states, provinces, departments or cities and municipalçities) is a type of public policy?

    Michaël Tatham

    Hi José,

    Maybe you find some of the below interesting. It is a mixture of older work (edited volumes by Keating & Aldecoa, and Michelmann & Soldatos) and more recent work on paradiplomacy (Criekemans, myself).

    They all deal with the topic of paradiplomacy understood as sub-state entities seeking to influence policy beyond the borders of their parent state.

    I hope this is useful!

    Best of luck with your research!


    Aldecoa F and Keating M (eds.). (1999) Paradiplomacy in Action: The Foreign Relations of Subnational Governments. London: Frank Cass.

    Michelmann H and Soldatos P (eds.). (1991) Federalism and International Relations : The Role of Subnational Units. Oxford: Oxford University Press.

    Michelmann H (Ed.). (2009) Foreign Relations in Federal Countries (Global Dialogue on Federalism). Montreal & Kingston: McGill-Queen's University Press.

    Criekemans D (2010) Regional Sub-State Diplomacy from a Comparative Perspective: Quebec, Scotland, Bavaria, Catalonia, Wallonia and Flanders. The Hague Journal of Diplomacy 5(1-2): 37-64.

    Criekemans D and Duran M (2010) Small State Diplomacy Compared to Sub-State Diplomacy: More of the Same or Different? In Steinmetz R and Wivel A (eds.), Small States in Europe: Challenges and Opportunities. Farnham: Ashgate, pp. 31-46.

    Tatham M (2013) Paradiplomats against the state: Explaining conflict in state and sub-state interest representation in Brussels. Comparative Political Studies 46(1): 63-94.

  • Johann Heider added an answer in Gateway Cloning:
    Will the F' plasmid in OmniMAX 2 cells be co-purified after transformation of pDONR?

    Hi there,

    the OnmiMAX 2 cells which come in the gateway cloning kit from Thermo contain an F' plasmid. So when I perform a plasmid prep after transforming OmniMAX 2 with my entry clone (pDONR/Zeo) wouldn't I be co-purifying some of the F' plasmid as well? 

    Since I have not seen any mention of this either in the manuals or anywhere on the web I guess it does not seem to be a problem, I would still be interested in an answer though :-)

    Johann Heider

    Episome means the same as plasmid. If F or F' episomes are integrated into the chromosomes, the resulting strains are called Hfr. The answer is that F has such a low copy number and is so much larger that "standard" plasmids that it is always expected to be out-competed in transformations. Most of it will probabyl also be entangled enough with chromosomal DNA to be separated from the (small) plasmid fraction during plasmid prep.

  • David Ian Walker added an answer in Cloning Vector:
    Blue/white E. coli clone screening without antimicrobial reistance?

    Does anyone know of a commercially available cloning vector (plasmid) that will allow blue/white screening of recombinant E. coli, but which does not contain any antimicrobial resistance genes?

    David Ian Walker

    I don't want to go into details as it is for a commercial project, but the idea I have in mind requires there to be no AMR in the clone. I know its going to cause me headaches down the line, but I'm just exploring possibilities for now.

  • Carsten Kettner asked a question in Enzyme Kinetics:
    Would you support the idea of the assessment on the completeness of enzymology data reported in your manuscript?

    Transparency and reproducibility of experimental data is a serious problem of present-day publications. There is a huge number of community-based initiatives that propose guidelines for reporting experimental data that should allow reveiwers and readers to interpret and re-analyze published data. However, reading or even following guidelines seems to be not very attractive; it burdens the authors additional labour virtually without benefit.

    So, what if a web-based software tool would be provided that support authors to check whether their data comply with reporting guidelines which are
    commonly accepted and even recommended by journals? This tool would require the input of minimum information about your experiment that aims to characterize a given enzyme. Major requirement is to keep this additional burden of data input as low as possible.

    The benefits?Just to name a few:

    • automatic clear statement whether the data reported in the manuscript are compliant with guidelines and support to improve the manuscript accordingly;
    • making research data transparent and reproducible, in brief: usable.
    • data sheet that can be submitted as supporting information which helps reviewers to interpret data;
    • contribution to a free enzyme kinetics database that provides experimental results along with information about assays' methodologies and conditions.

    The project: In order to gain a clearer view on the idea, please have a look at STRENDA DB.

  • Giuseppe Montesanto added an answer in Fish Parasites:
    What isopod lives on the eye of a Bicolor damselfish?

    This photo was taken on Bonaire, Dutch Caribbean. It shows a Bicolor damsel Stegastes partitus with a parasite on its eye. I guess it is an isopod. The isopod Anilocra partiti is known from this damselfish species, but it is supposed to attach under the eye. Also it should be coloured black to slate gray (Kensley & Schotte 1989).

    Maybe this is a small male A. partiti isopod before sex, colour and host location changes. But it might as well be another species.

    Does anybody know?

    + 1 more attachment

    Giuseppe Montesanto

    Nice... but I don't know!

  • Guomin Hua added an answer in CASTEP:
    Has anyone worked on characterization of composites by DFT on CASTEP??

    I want to know how to determine if my combination of super cell is precise also how to check its lattice mismatch and work function 

    Guomin Hua

    I think if you run the calculation on energy, you can estimate the lattice mismatch. but  as for the work function, you have to cut a surface, then subtract the Fermi energy from the potential in vacuum layer.

  • Banu Pradheepa Kamarajan added an answer in Methods:
    S.aureus identification and confirmation
    can anyone suggest me how do i identify and confirm a bacterium to be S.aureus
    Banu Pradheepa Kamarajan

    Simple and a basic biochemical screening test could be useful I guess. Streak your suspected cocci on the Mannitol Salt Agar. If the media turns yellow, it is S. aureus, if it remains red, then it is S. epidermidis probably! We use this test in our lab to ensure the culture is still uncontaminated! Hope this helps ;)

  • Venkata Krishna Bayineni added an answer in Western Blot Analysis:
    While I was using WB, I found lots of scattered band where I never expected. What is the reason?

    In my understanding of WB, band will be appear only where target protein in available, isn't that? 

    If that, then I should have band in the red marked portion. Why I have lots of scattered band in upper area? What does it mean? Is there my target protein remaining scattered? Or something else? 

    Please help to understand.

    Thanks in advance.

    Venkata Krishna Bayineni

    Dear Mr.Rashid,

    Even I have experienced this problem. I think you are using polyclonal antibody. If your antibody is polyclonal then they may produce large amounts of non-specific antibodies which can sometimes give background signal. Polyclonal antibodies not useful for probing specific domains of antigen, because antiserum will usually recognize many domains. 

    And also check if any problem with running the gel (Make sure there is no leakage or spilling of your protein during loading or handling).