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  • Flavio Theodor Kunreuther added an answer in Teaching Skills:
    Does anyone know of studies that examine teacher effectiveness in terms of leadership?

    One of the essential traits of a good teacher is the ability to motivate students.  Yet good portions of teacher evaluation systems center on communicating knowledge in various manners that encourage learning.  I have met teachers that have the pedagogical component mastered, yet do not seem to be effective teachers.  I have also met individuals who are proficient in their pedagogical component and are highly effective teachers.  

    The difference has been described as an intangible quality that the exceptional teacher possesses.  I am wondering if that intangible quality is related to leadership.

    The follow-up question then would be which components of leadership enhance teacher effectiveness?

     Is there such a construct as authentic teaching, that follows in line with the literature on authentic leadership? (Servant teaching, transformative teaching, moral teaching, etc.)  Does distributive leadership offer insight into learner-centered teaching practices?  The idea of leadership pedagogy 

    Flavio Theodor Kunreuther · University of São Paulo

    Rob, you might find interesting information on the National Outdoor Leadershio School - www.nols.edu. They are an experential leadership education school and one of the directors, John Gooking, conducts researches through the University of Utah. 

  • Andrey Chuvilin asked a question in Solid State Physics:
    What is phonon-plasmon coupling in graphene?

    Having very little knowledge about solid state physics, I wonder if someone would try to explain in simple words what phonon-plasmon coupling is and why is it of so much interest in particular in graphene?

    Does it mean we can pump the energy from plasmons to phonons and back? What this coupling adds to the fact that shining light on the sample we heat it, and heating the sample we make it shining? 

  • Jaime Cuauhtemoc Negrete added an answer in Basic Statistical Analysis:
    Can anyone suggest any publications or empirical formula on minimum number of subjects for an ergonomic evaluation?

    Can anyone suggest any publications or empirical formula on minimum number of subjects for an ergonomic evaluation?

    Jaime Cuauhtemoc Negrete

    Dear Dr.Shiv meavy this peper is useful for you

    Ergonomic evaluation of male and female operators during weeding operation.
    Article in Ama, Agricultural Mechanization in Asia, Africa & Latin America 41(2):26-29 · December  you can down load from research gate

  • Stam Nicolis added an answer in Gravitation:
    Is the proton mass to charge ratio equal to the plank mass?

    Using a proton charge 1.602*10^-19 coulombs is equal to proton mass 1.673*10^-27 Kg.

    One coulomb = 1.673*10^-27 Kg  divide by 1.602*10^-19

    Therefore One coulomb is equal to 1.044*10^-8Kg.

    Therefore One coulomb is approximately equal to a plank mass.

    Knowing that the gravitation constant G used for calculating a plank mass relies on acceleration due to gravity g measured in a given location, the two should be the same.

    Stam Nicolis · University of Tours

    In fact the ``proton charge'' (the electric charge of the proton) is the coupling constant of the proton to the electromagnetic field and (a) is dimensionless and (b) its value depends on the energy/length scale it's measured at. 

    The statement of the question is, in fact, meaningless, since the charge-to-mass ratio of the proton doesn't have the same dimensions as a mass, so their comparison doesn't make sense in any case.

  • Massimiliano Nori added an answer in Phase Equilibria:
    What is the physical meaning of the EOS energy interaction parameter (i.e. combining rule parameter for the binary) in a multi component mixture?

    In order to apply an EOS to the description of phase equilibria  (e.g. VLE ) of a multicomponent mixture are often applied mixing rules ( e.g. Van der Waals ) that rely on combining rules for the binary mixture parameters. What are the  assumptions that justify this method?

    Massimiliano Nori · Saipem S.p.A.

    Dear Ilya,

    Thank you for your explanation. In order to extend binary mixtures regressed parameters to multicomponent mixtures, is k12 assumed independent of other components present in the mixture ?  

  • Marianna A Maretina asked a question in RNAlater:
    What is the best way to purify samples (peripheral blood mononuclear cells) from RNAlater for futher usage in ELISA?

    Is PBS wash an appropriate method?

  • Mehdi Elmoukhliss added an answer in Crowdsourcing:
    What is the best voting method to use in crowdsourcing ?

    Crowds evaluate contributions.

    It seems that "likes" are mainly social grooming stuff, not really good predictor of content quality. At least it shows "popularity", but the link between popularity and quality is not evident.

    Stars and more complex scales seems better (Riedl et al 2010).  But I didn't find literature about new options (e.g. emotional icons).

    Any idea ? I'll give you at least 4 stars ! ;-)


    Mehdi Elmoukhliss · Telecom Business School

    The question of whether collective intelligence is social or not is really important. Too many scientists consider it just 'aggregating' (mathematically) individual opinions. In the other hand, social influence is strong and not a must at all... I think it shall depend on the nature of the activity taken in charge (routine tasks vs evaluation vs creating vs deciding)...  An interesting topic ! Thank you very much for those elements.


  • R. M. Sanabria added an answer in Building Codes:
    Apart from Asbestos, are there other dangerous building materials still being condoned in building structures that harm humankind?

    Is Asbestos the only and most harmful building material against humankind?

    R. M. Sanabria · Oak Ridge National Laboratory

    I think a scale should be developed and limits set.  The casual comparison of some of these building materials with truly harmful stuff, in the same sentence, seems to me to be unfair.

    For what it's worth, in my current project halogens were banned from not only building materials but even from the equipment/components themselves.  These include, most notably, fluorine and chlorine.  Word is in case of accidental fire they become lethal gases.

  • Rui Goncalves added an answer in Applied Geophysics:
    How might I detect city road cavities using geophysical method?

    There are many caves in city's road in China. 277 cavities were found in Beijing from 2007-2009. 80% of caves happened at depth between 0 - 5m. 20% of caves happened at depth between 5 ~ 6 m.

    Many peoples are dead because of road cavity. This tragedy almost happen every day in China. If geophysical methods do good job, this will save a lot of people. 

    Rui Goncalves · Polytechnic Institute of Tomar

    The fastest method for detection would be GPR (or EMI).

    As stated, we can have natural cavities (e.g. under carbonate rocks) or artificial cavities developed by water/sewer underground pipe leakage at “loose soil” (e.g. sandstone).

    The targets - cavities can be filed (totally or not) with air (high electrical resistivity), sediments or water (mean to low electrical resistivity).

    Fortunately the cavities’ s size and depth hazard will follow the penetration deep versus target size of methods’ s detection, i.e. deeper smaller cavities are not detected –

    but they are not dangerous. For this reason, GPR would be the fastest and less prone to EM interferences at cities.

  • Andreu Castellet added an answer in Communication Research:
    Is anyone interested in a think tank on entrepreneurial journalism?

    With the support of researchgate I found some researchers, that were interested in founding a think tank on the topic of entrepreneurial journalism. We have observed, that the national communities of researchers dealing with this topic are too small. So we thought that a virtual connection might be of interest for some people here? And if we find a few people, we can think about actions. If you are interested, please send me a message on researchgate.


    Andreu Castellet · University of Murcia

    "Once a jibser, always a jibser", you know that. Don't advertise it too much. JIBS is the best-kept secret in European academia -:). I hope we figure out something interesting to develop through this network.



  • Chathranee Anumitha Jayathilake added an answer in Matrices:
    What are the areas in graph theory that we can use matrices?

    There are several important areas in graph theory such as shortest paths,trees, coloring etc.Adjacency and incidence matrix of a graph is one famous application of matrices in graph theory. What are the other areas in graph theory that involve matrices? 

    Chathranee Anumitha Jayathilake · University of Peradeniya

    Thanks Prof.Miodrag. Your answer was very useful to me. I was searching a book like that..

  • Matts Roos added an answer in Astronomy & Astrophysics:
    An old question that is still fresh: Is gravity a Newtonian force or Einstein space-time curvature?
    No gravitational wave was measured yet, no graviton was detected accordingly. On the other hand no space- time curvature was observable. There is no successful experiment to validate the current theories. What is the nature of the mysterious gravity? What is the velocity of this effect ?
    Matts Roos · University of Helsinki


    I agree with the first two paragraphs of  your answers to Parviz. The third paragraph I do not understand probably because it tries to answer ameaningless question.

  • James Montaldi added an answer in Intersectionality:
    Is it true that the fixed locus of a locally complete intersection W under an action of a finite group G is also a locally complete intersection?

    It is well-known that if the variety W is smooth, then the fixed locus is also smooth.

    I have tried to prove this by embedding W into a G-representation V with W invariant, using the fact that V^G is smooth, but so far I could not work this out completely. Any good idea?

    James Montaldi · The University of Manchester

    Good question, but I believe the answer is 'no' (suprisingly).  Here is an example:
    My favourite non-c.i. is the 3 lines in C^3, with ideal <xy, yz, zx>, call it Z.  Now consider the 3-dimensional subvariety X of C^6, with variables a,b,c,x,y,z,  given by equations
    a^2 - xy = 0,
    b^2 - yz = 0,
    c^2 - xz = 0.
    By dimension count, this is a c.i. (and is reduced).  Consider the action of the group Z_2 of 2 elements, by reversing the signs of a,b,c but acting trivially on x,y,z.  This action preserves X (indeed each generator is invariant). Then Fix (Z_2, C^6) is {a=b=c=0}, and so Fix( Z_2, X) = L, which is not a c.i.

    So the interesting question is, when is Fix(G,X) a c.i., given X is a c.i.?


  • Ashok Kumar asked a question in Micropropagation:
    Is there any simplest method which can be used for virus indexing in nagpur mandrin and mosambi plants for micropropagation work?

    I will use them in STG technique.

  • Ranjani K. Murthy added an answer in Rural Areas:
    Can anyone intrested in research about Squatter areas and social life to rehabilitat and redevlopment for quality of life?

    Squatter areas is a very important issue , the people migrate from rural areas to live in urban areas with their behavior and they built non organize building with low materials and without permission , no sanitary work, no infrastructure , the quality of life is negative.

    Ranjani K. Murthy · Independent, India

    Yes the quality of life in squatter homes is appalling in parts of India, Bangladesh and Nepal that I have seen.  Apart from rural urban migration is inter-state migration and illegal migration from other countries. One needs to distinguish between illegal settlements (not recognised by government) and legal ones. The latter may have health, education, police posts and other services provided by government, while   these are not there in the illegal settlements. There are gender specific issues like the rate of violence against women, masculinities and alcohol/substance abuse, inadequate access to drinking water, poor sanitation facilities, poor access to energy for cooking and so on.  Illegal tenements are often in low lying areas and these are prone to floods.  Government policies for poverty reduction and women's rights are stronger for urban areas than rural areas. Elderly care support is minimal, and .there is little community support available    This is in contrast to the increase in rural-urban migration. 

  • Richard Allan Dale added an answer in Community Health:
    What is the most important priority in health promotion?

     Health promotion is very relevant today. There is a global acceptance that health and social wellbeing are determined by many factors outside the health system which include socioeconomic conditions, patterns of consumption associated with food and communication, demographic patterns, learning environments, family patterns, the cultural and social fabric of societies; sociopolitical and economic changes, including commercialization and trade and global environmental change. In such a situation, health issues can be effectively addressed by adopting a holistic approach by empowering individuals and communities to take action for their health, fostering leadership for public health, promoting intersectional action to build healthy public policies in all sectors and creating sustainable health systems.What is the most important priority in health promotion? What is your opinion about it?

    Richard Allan Dale · City of Gothenburg

    I agree with Supatra. which is the situation and needs of your target Group?

    Many times we deal with different Groups....

    For some you need to provide security, food, Clean water and shelter (basic to survive)

    For those that have the basic to survive you may need to provide education, work, social network (basic to live)

    Some others may need respect, possibility to develope, possibility to promote Changes in their Life (such as being able to select healthy habits)

    Some may need time to rest because their lives are so Active.

  • Emad Hasabeldaim asked a question in South Africa:
    I am asking about GAS PYCNOMETER equipment for powder density measurement. Is there is any university or institute in south africa has this machine?

    any one know tell me please.

  • Anura Dissanayake added an answer in Semen:
    Can a semen sample have low motility with high MMP by Flow cytometry?

    Dear colleagues,

    Recently we had a couple of cases where there was low forward motility(5%) with a high MMP(Mitochondrial Membrane potential by JC1) value. Does anyone have any experience with such cases and the future course of investigations?

    With regards

    Anura Dissanayake · University of Kelaniya

    Sorry I made a mistake. You can ectract protein and analyze using SDS page. It is not RT PCR.

  • Ersin Avci asked a question in Abdominal Surgery:
    What is the gold standart after abdominal surgery for physical function? especially in early period ?

    after abdominal surgery patients have severe problems to maintain their functional status and it is also hard to measure it. now I am working on a physical function test and ı need a gold standart for statistics and measurement.

  • Mahabubur Rahman Chowdhury added an answer in BET:
    What does negative volume adsorbed mean in BET analysis?

    I got some BET results. When i plot the relative pressure (P/Po) against the volume adsorbed the curve goes to negative (below the x axis). What does this means. And after a certain point the desorption curve is below the adsorption curve. It should have been the opposite. Can somebody please help. I can send the xcel files if somebody is interested to help analyse the data.  

    Mahabubur Rahman Chowdhury · Cape Peninsula University of Technology

    This is what i get. Can some body please help to explain whats happening. Its type III i guess meaning the samples are non porous?? 

  • Assma Azeroual asked a question in OpenCV:
    Read/write uncompressed videos?


    Please, i am using opencv 2.4.9 on ubuntu 14.04 and i try to read/write an uncopressed video but it gives me a segfaults on cvQueryFrame(capture) when i try to open a rawvideo. Can help me?

    Thank you

  • Aziz Ullah Khan added an answer in Adverse Drug Reactions:
    Is Tigecycline use associated with varicella infection? If yes, why, and how?

    Is Tigecycline use associated with varicella infection? If yes, why, and how?

    Aziz Ullah Khan · Northwest General Hospital and Research Centre

    Dear Sonali!
    No clinical study is present in literature regarding tigecycline induced vercella infection. If you have read something like that, it would be interesting if you could share that.

  • Gayashan M. Arachchige asked a question in Fish:
    Can anyone guss these marine fish species?

    These marine species were photographed during the field works. I have identified most of them but I some doubt on identifications. So I would like to have your identification too.. Thanks

  • Monica Leu added an answer in Homocysteine:
    How does vitamin D affect Homocysteine level?

    Methionine can be metabolized to homocysteine. Homocysteine level is increased by  deficiency of folate, Vitamin B6 and12. I am just curious to know if there is any effect of Vitamin D on the level of homocysteine? 

    Monica Leu · University of Gothenburg


    I am also interested in this question. Would you know if there are epidemiological studies that have investigated the relationship between these two markers?

    Thank you,


  • Jayprakash Yadav added an answer in Antimicrobial Activity:
    Can i used commercial disc as positive control in agar well diffusion method?

    I want to screen antimicrobial activity of certain extracts, and i choose to do agar well diffusion method. For positive control, can I used the standard antibiotic and placed it on the agar, instead of using antibiotic solutions in the respective wells? thanks in advanced! =)

    Jayprakash Yadav · National Institute of Technology Rourkela

    dissolved the commercial disk in 100ml solvent that you used for extraction and use as control.

  • Hopewell Molefe asked a question in Effluents:
    What would theoretically be an optimum pH for precipitating Sodium Sulphate?

    I have achieved significant success in reducing my sulphates in the effluent by dosing calculated quantities of lime Ca(OH)2. I found that I reduce the most sulphates out the optimum ph range is 9-13. I want to try and see if I cannot reduce my sulphates even more by forming sodium sulphate Sludge as well Na2SO. This I would achieve by using my expired stock of the following powders: Na2CO3, NaHCO3 CaCO3. I know I might be forming a lot of carbon dioxide. Please any advice or Experience on this.

  • Immanuel Jebsen asked a question in Organizations:
    "Glocalisation": What are some of the advantages and disadvantages for consumers?

    Does glocalisation always work? What are some of the advantages and disadvantages for consumers when organisations adopt a “glocalisation” approach towards them? 

  • Nguyen Nuong asked a question in Fixed Cell:
    How long the whole blood sample can be stored before flow cytometry analysis?

    Hi everybody,

    I want to detect CD4/CD8 T lymphocyte in the mouse whole blood samples by flow cytometry. Because the flow cytometry is not ready in my lab and I need to collect the samples, I want to store the sample for 3 days. What should I do? I think about 2 options: (1) store the whole blood samples until I'm ready to analyse, (2) stain the sample with labelled antibody, fix the cell with PFA 1%, after that store the sample.

    Hope your help!

    Many thanks!


  • Lauren Fleming asked a question in Mitotracking:
    Mitotracker green FM staining protocol for fixed cells/cells to be fixed?

    Has anyone had any success using mitotracker green FM on fixed cells/live cells which were then fixed? I know the online information suggests it is not retained well following fixation but I was wondering whether anyone had found a method by which they were able to retain a fair amount of the staining?

    Thanks for your help!