Q&A

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  • Roland Iosif Moraru added an answer in Lecturing:
    How do you organise yourself so that you utilise more of your activities in generating productive research outputs?

    In a lecturing position, we get involved in teaching, mentoring, professional and community service, and formal research projects. Our traditional research may not be the only way that we are making meaningful publishable contributions. How do our most productive peers harness their diverse contributions to enhance their research and publication outputs?

    Roland Iosif Moraru · University of Petrosani

    Dear Marcia and friends, time management revolves around one essential rule: that time is not allocated randomly. You must actively distribute time amongst your activities. Breaking activities down into tasks presents you
    with a more realistic approach to allocating your time.However, there are different sorts of activities which demand different sorts of time. We need to consider the type of work which needs to be done and the amount of consecutive time needed to do it. 

    Another important hint: Plans should be as realistic as possible.

  • Yash Sharma added an answer in Protocols:
    Is there any protocol to estimate the amount of Total alkaloid content in a compound except UV spectrophotometry method?

    I have read some protocols but they have some chemicals like borosilicate green which are not easily available in lab so I want such protocol that can be easily done in lab and dont take maximum time.

    Yash Sharma · Amity University

    Thank you so much 

  • Ric Berlinski added an answer in Poultry Nutrition:
    Why are insects not allowed in animal feed?

    I read a paper about this subject. But I'm confuse, actually  can we use insects in poultry feed without any problem?

    Ric Berlinski · Toledo Zoo

    Insects can be vectors for many parasites, as well as many organisms that induce disease.  I would strongly caution against it, but that is simply my experience as a zoo vet

  • Andrej Halabuk added an answer in Drought:
    What are drought effects on rangeland? How can determine this effects by remote sensing?

    Which method and product ?

    Andrej Halabuk · Slovak Academy of Sciences

    Depending on type of the vegetation and period of extreme drought or heat wave you can also analyze the different shape of the annual profile of NDVI, For example, when summer heat occurred, the second peak of the curve does not occurred in  temporal grasslands.

  • Are there volunteers to be advisors if not supervisors for PhD students of developing countries?
    In developing countries, it is difficult to find mentor/supervisor for PhD students who want to pursue their research(s) in new areas such as VGI, SDI, Spatial Data Mining, Spatial Agriculture, m-governance and crowd sourcing etc. The reasons include brain drain. Therefore, to reduce digital divide in a sense, researchers/scholars/institution who can contribute to advise students especially of developing countries voluntarily are requested to help out.
    Jan Kunnas · University of Turku

    Hi Costas, graduate students can and in my understanding also ask questions at RG already. Do we really need different levels at RG? 

  • Andrea Sanchini asked a question in tRNA:
    It is known that presence of tRNAs is a hotspot for genomic island insertion: do you know if this tRNAs or their position has a role in pathogenesis?

    I am working with genomic island and it is well known that the presence of several close tRNAs represents an hot spot for genomic island insertion due to recombination events. Do you know if this tRNA may have any role in virulence or pathogenesis? Or do you know if a different position of these tRNAs in the Island may have any role? Or any publication regarding that? Many thanks!

  • Yagna PR Jarajapu added an answer in Adipose:
    How do you isolate mature adipose cells from mouse bone marrow?

    Hi!

    I am trying to isolate adipose cells from  mouse bone marrow. I am using the ceiling  culture method, but so far I cannot see any cells at all  after collagenase I treatment. I see a bit of a clear phase floating at the top of the tube, but no  cells shows up  under the microscope. Ideas?

    Thank you

    Yagna PR Jarajapu · North Dakota State University

    David, I had the same experience too, in a normal mouse you wouldn't expect many cells for harvesting. You may try doing this in a fat mouse, db/db or ob/ob, or a zucker rat then you would. You can also feed a mouse or rat with high fat diet to get a good harvest.

  • Steven Bonacorsi asked a question in Lean Six Sigma:
    Please Share how you will use the Lean Six Sigma Define Phase Tollgate Templates?

    Please share any recommended Lean Six Sigma Define Phase template or tool improvements as I update these templates each year.

  • What is the most important reason that leads to the definition of the trigonometric functions?

    In mathematics, the trigonometric functions or the circular functions are functions of an angle. They relate the angles of a triangle to the lengths of its sides. The most familiar trigonometric functions are the sine, cosine, and tangent. In the context of the standard unit circle (a circle with radius 1 unit), where a triangle is formed by a ray originating at the origin and making some angle with the x-axis, the sine of the angle gives the length of the y-component (the opposite to the angle or the rise) of the triangle, the cosine gives the length of the x-component (the adjacent of the angle or the run), and the tangent function gives the slope (y-component divided by the x-component). More precise definitions are detailed below. Trigonometric functions are commonly defined as ratios of two sides of a right triangle containing the angle, and can equivalently be defined as the lengths of various line segments from a unit circle. More modern definitions express them as infinite series or as solutions of certain differential equations, allowing their extension to arbitrary positive and negative values and even to complex numbers. Trigonometric functions have a wide range of uses including computing unknown lengths and angles in triangles (often right triangles). In this use, trigonometric functions are used, for instance, in navigation, engineering, and physics. A common use in elementary physics is resolving a vector into Cartesian coordinates. The sine and cosine functions are also commonly used to model periodic function phenomena such as sound and light waves, the position and velocity of harmonic oscillators, sunlight intensity and day length, and average temperature variations through the year. In modern usage, there are six basic trigonometric functions, tabulated here with equations that relate them to one another. Especially with the last four, these relations are often taken as the definitions of those functions, but one can define them equally well geometrically, or by other means, and then derive these relations.

    http://en.wikipedia.org/wiki/Trigonometric_functions

    Fernando Herrero Carrón · Indizen Technologies SL

    Dear Abedallah,

    I think the most important reason is an antropologic one, namely the marvelling of the human mind in the presence of invariants in the universe. When humans began realizing that certain ratios were preserved invariant across different scales (think of pi, independent of the radius of a circle, the golden ratio, etc.), they began searching for more of these properties. And, as you mention, sines and cosines are very related to circles, so to me it comes as a natural consequence of the study of the circle and pi.

    Cheers,

    Fernando

  • Nawaz Ahmad added an answer in Modeling:
    If we have a categorical dependent variable i.e. Y= 1,2,3,4,5 and binary independent variables, what will the regression method be?
    Multinomial or crdered choice. Which one is applicable?
    Nawaz Ahmad · Indus University, Karachi, Pakistan

    logistic regression model

  • Emeka W. Dumbili added an answer in Peer Review:
    Is blind peer review better than open peer review?

    I attended a seminar and one of the attendees narrated an ugly experience he had. He said that a journal rejected a manuscript researchers from his research institute submitted based on comments one of the reviewers made. These comments were personal, defamatory, etc. He added that they later learnt the reviewer's identity. Unfortunately, the reviewer earlier had a personal issue with the research centre that submitted the paper, so his review was based on personal grudges. Would open peer reviews help to reduce or eliminate this and other similar experiences?  I would like to know the merits of both and which is preferable.

    Emeka W. Dumbili · Brunel University

    Thanks Peter for your insightful contribution. As a student (early career researcher), I am learning from these contributions and I quite agree with you that open review is better. If a reviewer is not willing to reveal his/her identity, something may be wrong. Though as some contributors noted, open review may take longer time but I will rather wait than to have bad reviews.

  • Jenkins Macedo added an answer in Biochar:
    How would you analyze overhead sprinklers spray distribution?

    We recently used overhead sprinkler systems for irrigation during a field research, which involved biochar & fertilizer trial on morning glory. We collected sprinklers spray water samples (ml) for 30-day after each time we irrigated and we would like to analyze these to show the irrigation spray distribution and uniformity. Which statistical approach/application would you recommend? We would like to show this in a graphic form, however, not in table. We currently have the data points in tabular form. Thanks for your insights.

    Jenkins

    Jenkins Macedo · Searching for Employment

    Pilesorts statistical analysis is one approach I am thinking to use by diving the collectors into four quadrants according to compass (East, West, North, and South) and how the collectors were distributed in each of these quadrants and then adding the respective collector IDs and the numerical data for each spray collector per quadrant. We installed 120 spray collectors [see pictures attached] and measured the water content in ml after each irrigation event, but I was thinking there could be an other way to graph this.

  • Jeremy Causse added an answer in Nanochemistry:
    Does anyone have any references about thermogravimetric/differential thermal analysis of Pluronic 123 (P123, M = 5800)?
    I want know about the TG/DSC results of P123 in inert atmosphere.
    Are there any references?
    Jeremy Causse · Atomic Energy and Alternative Energies Commission

    Hello,

    We did TGA on P123  (1000°C) under Argon atmosphere  one or two months a go to know if there was still residual carbon after the heating treatment.. And the answer is no. We were also surprised to see that there was almost no water inside pure P123 (Sigma Aldrich).

  • If any coordinates will do in General Relativity, is spatial curvature necessary? Is GR more complex than necessary, and is curvature verified?

    GR was introduced along with the principle that not only is no coordinate system preferred, but that any arbitrary coordinate system would do.  The complex mathematical machinery of covariance was introduced (including tensors) to express the laws of physics, any of the laws not just GR, in arbitrary coordinates.  This allows coordinate systems in which the distances vary with position and orientation, and in which the speed of light is non-isotropic (varies by direction), and such coordinates are routinely used in famous solutions such as Schwarzschild.

    So, it is not just the curvature of Riemannian geometry that requires complexity, but most of it is required by independence from coordinates.  And if indeed physics is independent of coordinates, can coordinates be found for solving GR problems in which space (if not spacetime) is flat and therefore graspable to the ordinary intuition?

    For an introduction to analysis of orbits using only time dilation, not  spatial curvature, see paper linked below.  GR was derived from the equivalence principle on the assumption that curvature was the only way to explain equivalence, but this is an argument not a proof according to GR verification authority Cliff Will.  If another method is available, it becomes a weak argument.  Is there empirical proof of curvature?

    Charles Francis · Jesus College, Cambridge

    I don't think it matters if inertial observers at different heights drift apart, since as you say we are only interested in what the one observer in the elevator thinks about the speed at different heights. I am very happy with the derivation using isotropic coordinates for the Schwarzschild solution, as I was really just trying to find a simpler way of doing this, but now I am concerned with whether there is a form of the equivalence principle which is actually valid in general relativity, or whether the principle is of only historical and handwavy interest. It seems to me that if I am right, then it is valid, but if you are right it is not. 

  • Esteban Basoalto added an answer in Moths:
    What kind of traps are the best to use as fruit baited trap for catching moths?

    See above

    Esteban Basoalto · Austral University of Chile

    What do you want to do, monitoring or catch them alive?

  • Ediz Coşkun added an answer in Base Sequence:
    Why in the beginning and ending portions, approximately 200 base sequences of my gene aren't clear as much as the middle parts of my gene?

    In total, I have a gene which has 896 bases. After DNA sequencing process (as I mentioned in the title), approximately both are on the beginning portion. Almost 100 bases at the beginning portion, and the ending portions have almost 100 bases. These appear to be like  mixture, two or three pick seemed in the one base section of my gene. But for the remaining part in the middle, about 400-500 bases have a completely clear dna sequence all the time. 

    What is going wrong in the beginning and ending sections? Truly, I wonder it.

    Ediz Coşkun · Istanbul University

    Mr, Artur I added picture of my noise gene sequence which you wanted. I'm waiting to your answer. Sorry for late return...The file in the attached.

  • Should profit be one of the main motives of Public Sector Enterprises?

    Public sector enterprises are run by Governments across the world with some social welfare in mind and towards contributing to the development of the society. Many are not-for-profit organizations - and it is said that funding is provided at the beginning to establish public sector enterprises and in the long run, they should be self-sustaining. Research grants are generously given also for the academic & research institutions in the public sector. The question is - should the public sector enterprises work with "profit motive" too? I welcome your views on this! - Sundar

    Nageswara Rao Posinasetti · University of Northern Iowa

    Public sector employees have been developed for a purpose to provide service as well as enforce the government regulations. To that extent they have a different set of work environment, loyalty and reasons to be part of Public sector enterprises. Though profit can be one part of motive, it cannot be the sole motive. Here are a few references that examines the public sector employees in different countries.

    1. Dixit, A. (2002). Incentives and organizations in the public sector: An interpretative review. Journal of human resources, 696-727.
    2. Mascarenhas, R. C. (1993). Building an enterprise culture in the public sector: reform of the public sector in Australia, Britain, and New Zealand. Public Administration Review, 319-328.
    3. Borzaga, C., & Tortia, E. (2006). Worker motivations, job satisfaction, and loyalty in public and nonprofit social services. Nonprofit and voluntary sector quarterly, 35(2), 225-248.
  • Henry Kazula asked a question in Plastics:
    Activated carbon

    Am working on recycling of plastic bags,am finding a technique to recycle plastic bags chemically applying new tech...

    Is it possible to make activated carbon from plastic bags? I didn't find a paper from renowned journal explaining on the same...Anyone with further information?

  • Veronica Goss asked a question in Business:
    Are Americans becoming ruder in ther interaction with one another in the business environment

    Are Americans becoming ruder in ther interaction with one another in the business environment

  • Scott Russell added an answer in Hegel:
    Did Adorno accomplish, what he sought to do with his major work on "Negative Dialectics"?

    In his book "Negative Dialectics" Theodor W. Adorno sought to provide a new approach to philosophical dialectics, based on and criticising Kant, Hegel, Marx, and rather destructive Heidegger. In doing this he tried to avoid any essentialistic manner and point of view, but could not help himself, but to choose rather polemic language when it comes to Heidegger or the Shoa and its consequences for philosophy. 

    The question, therefore, would be: did he or did he not accomplish a "negative dialectics", which truely avoids mistakes and essentialism that previous dialectics failed to see?

    Scott Russell · University of Michigan-Flint

    I have wondered about that curious little circle of Heidegger-Adorno-Derrida too. (By the way, the Deleuze-Guattari effort that moves from psych to political theory, yes!) For me, there is an interesting differance between Heidegger and Derrida, though you might read this otherwise: where Heidegger attempts to complete a dasein whose world is always, already revealed by dasein's entry (clearing in the woods, lichtung) for whom presence anticipates the conditions of past, present, future, Derrida is much more interested in the language problem of the entire exercise. Then, Derrida's "anti-dialectic" is the problem of antithetical oppositions that exist only because of each other, creating the mutual possibility of a difference/meaning. Where Heidegger loves etymology, Derrida loves synonymy. One is a phenomenologist and the other an anti-philosopher. Adorno's mission is quite different, though there are, as you say, useful similarities in the tools they attempt to invent.  "A semantic taboo strangles substantive questions, as if they were only questions of meaning;" -- ND part III

  • Bimo Hernowo added an answer in Cultural Heritage:
    What are the odds of intangible heritage disappearing without tangible heritage?
    There is a current focus on intangible heritage, reactive to a long period where tangible heritage was priority. I wonder if one can be protected without the other. I wonder if one survives without the other. What do you think?
  • Nawaz Ahmad added an answer in Forecasting:
    How should I forecast my data, if I have 5 years record only?

    How should I forecast my data, if I have 5 years record only? any method of estimation for next 5 years?

    Nawaz Ahmad · Indus University, Karachi, Pakistan

    Dear Asma,

    You have 5 years record, BUT what is nature of record? Is it time series, cross section, panel, or some other type of data? 

    If it is time series, then uni variate or multi variate ?

    Usually, in univariate time series data, ARMA (auto regressive moving average) models are used to forecast. Its available in E-Views 

    Hope it helps, if not you can post.

  • Abedallah M Rababah added an answer in Polynomials:
    Does anyone have knowledge on legendre approximation?

    If we are going to approximate a smooth function with legendre polynomials then is there relation that guarantees that the expansion coefficients decay ,Can we calculate the error bound of the approximation? If any one know about the problem I will be thankful if you let me know

    Abedallah M Rababah · Jordan University of Science and Technology

    Dear @Hammad, approximating using the Legendre polynomials as basis has the same rules of convergence like any series expansion; it has only the advantage of simplicity and direct computation of the series coefficients because of orthogonality w.r.t. weight function 1.

  • Are there any researchers interested in the health problems students face as a result of our current educational model? E.g. stress levels, depression
    I'm a 3rd year undergraduate student in the School of Public Health Systems in the University of Waterloo. I'm extremely interested in teaching and researching novel methods of education in order to tackle many of the problems students (both at a high school and university levels) face today. Some of the problems that I'm interested in researching include stress levels, depression, use of drugs on campus, the alleged ADHD epidemic, etc.

    I would appreciate any input as i am quicky approaching my thesis development but I unfortunately cannot find any higher PhD students or professors who are interested in this field!

    Thank you!
    María de la LUz Casas · Universidad Panamericana Sede México

    Hello all the investigators in bulling against medicine students.
    We are working a thesis at national level on this serious problem in Mexico, the survey will be applied in September and we will have results in  this year, We can share them to you.
    Perhaps when you have  your survey results we can do a international comparative study. Of course the study can include health professionals, specially nurses.

    Please send to me your e-mail in order to further contact. 

    thank you

    Maria de la LUz

  • What do you think about an equation to precisely predict happiness?

    BBC report says scientists have developed a mathematical equation that can predict momentary delight. They found that participants were happiest when they performed better than expected during a risk-reward task.
    "We can look at past decisions and outcomes and predict exactly how happy you will say you are at any point in time," said lead author Dr Robb Rutledge from University College London.
    What is your opinion about this research? Now that we have an equation which can we use it in survey research to replace a Likert scale for such questions? Any further comments will help. Thanks.

    Robb B. Rutledge, Nikolina Skandali, Peter Dayan, and Raymond J. Dolan - A computational and neural model of momentary subjective well-being, August 4, 2014, doi:10.1073/pnas.1407535111

    Costas Drossos · University of Patras

    Happiness exists because there is unhappiness! Thus is there is an "equation" it should include also unhappiness and motion form happiness to unhappiness and back. That is the equation should be a kind of dialectical one. Dialectics in mathematics is only possible through the concept of adjoin functors. By just describing happiness it is not appropriate and it is rather a metaphysical one.    

  • Chao Shen added an answer in Physics:
    What are the dimensions in the sedov blast formula?

    Sedov blast formula:

    R=a*(E/p)^1/(2+n)*t^2/(2+n);

    I want to calculate the deposition energy E by fitting between R and t. What are the units of R, t and p when using this formula?

    And the calculated E is J or mJ? 

    Chao Shen · National University of Defense Technology

    thank you !@Sergei Sergeenkov@Alexey A. Ilyin 

  • Mark Thompson added an answer in Chloroform:
    Is chloroform suitable for cell culture experiments?

    Please suggest me whether minimal amount of chloroform (0.1%) is suitable to use in cell culture experiments. As my organic compound shows degradation behavior in DMSO solvents, I prefer using an organic solvents to carry out my biological experiments. But there is another problem where organic solvents can't be miscible with cell culture media. So please suggest me any suitable organic solvents for doing cell culture experiments.

    Thank you. 

    Mark Thompson · The University of Sheffield

    If I have a compound which isn't stable in DMSO, I usually make up a fresh stock for each use. If you can't do that, then ethanol or isopropanol should be fine, as others have said. You might also get away with acetonitrile. Just be sure to use the appropriate vehicle control whichever way you go, and all should be OK.

  • Jenkins Macedo added an answer in Air Quality:
    Is it possible to monitor air quality by remote sensing satellite imagery?

    We normally monitor air quality by measuring pollutant gases such as CO,COT,SO2,NH3 and H2S by special instruments. But this is very costly. Remote sensing will be more economical and effective if we could measure these gases using satellite imagery. 

    Jenkins Macedo · Searching for Employment

    Yes, you can. However, it could have its own disadvantages [spatial resolution of the remotely sensed datasets, the effects of cloud cover and other meteorological features] and the limitedness of remotely sensed data regionally and globally. However, if your research has the financial backing, I would say, why not do it. Good luck! 

  • Gordon Gates added an answer in Philosophy:
    Can philosophical discussion be made worthwhile for the general public?

    In my planned book "Philosophy for Everyone", my answer is yes, but...Philosophy as usually taught and practiced by academic Philosophy Departments and philosophers turns most people off--and rightfully so.  Before we got converted to academic philosophy, think of what got us interested in philosophical questions in the first place.  The essence of 'Philosophy', embodied by Socrates, is an approach to seek the truth in order to be able to live our lives more wisely.  It shouldn't be an academic exercise or contest to be clever with words or to baffle non-philosophers with 'deep' though obscure thoughts--intended only for the elite few.  Nor is it the history of what philosophers have said or of so-called philosophical issues, most of which is incomprehensible and irrelevant to non-philosophers.  If Socrates really is the Father of Philosophy and this claim isn't merely lip service by philosophers, it's perhaps time to learn what he actually had to teach.  Socrates' most important contribution are not his personal views, but his approach to resolving differences of philosophical opinions in open discussion with the common people. Socrates' approach is not the same as the Socratic Method.  His method is but one application of his approach. His method is only the tip of the iceberg.  What do you think?  Am I on the right track or am I off?

    Thanks for clarifying your position Jonathan. I think it's fascinating that you got your MA in philosophy after retiring from a career in science. I got mine when I was still a runny nosed kid looking to understand himself. Thanks everyone for your participation in this forum and all the food for thought. In the area of practical philosophy, maybe professional philosophers should be seen as facilitators because of their commitment to the field rather than experts whose opinions have any privileged position. We look forward to your book Albert; it sounds like you have the humility to pull it off. My advice would be to put communicative solidarity and engagement at the center rather than any one philosopher's approach.