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  • Eduardo Manzanares added an answer in Epistemology:
    Does anybody has information about epistemological and ontological investigations on cuantitative research?

    I'm about to start a new research over this subject. 

    I'd appreciate your help if you have some information to share with me.

    Thanks in advance;


    Eduardo Manzanares · Universidad de las Naciones

    Thank you Tony. I've done it and it's very interesting. My point is that the same approch can be addressed simultaneously from the ontological end epistemological perspective. Of course, it has to be proven.

  • Can we consider software agents (SA) and Multi-Agent Systems (MAS) as soft computing techniques?

    Since their definition in 1994 by Zadeh, soft computing has been improved with a lot of techniques. Why if the fundamentals of SA and MAS are so close to soft computing definition, yet are not considered as soft computing techniques? If I wrong, please, in what paper or scientific work can I find a citable answer? Thanks in advance.

    Rafael Bello · Central University "Marta Abreu" of Las Villas

    Software agents (SA) and Multi-Agent Systems (MAS) can be considered soft computing techniques depending on how the agenta are built. If the agent is developed using some of the softcomputing techniques (using fuzzy sets, neural networks, metaheuristics, bayesian reasoning, etc) the MAS could be considered in the SC.

  • Justin Lemkul added an answer in Gromacs:
    How can i solve the Gromacs error in md simulation. ?

    In grompp in ion.trp filr creation there occur error. Fatal Error, Too much Warning (1), use option -maxwarn. could anybody tell me how to use this option, if i use this option its asking for argument. how can i solve this problem ?

    Justin Lemkul · University of Maryland, Baltimore

    grompp prints out notes and errors.  Notes are informative.  Errors indicate something badly wrong with the input.  You shouldn't use -maxwarn to simply circumvent the problem, you should rectify the error, whatever it is.

  • What are the possible theoretical frameworks a data mining project may have?

    Students prediction,Educational data mining.

  • Is there a practical benefit of personalized medicine in oncology care?

    Science has provided us with countless discoveries thought to potentially improve cancer outcomes. However, only a handful of them have been translated into clinical care, and at a quite prohibitive price tag (eg new generation TKIs, monoclonal antibodies, genomic testing etc). Some other, more cost effective, are yet to be fully adopted by health care providers. Among the later I would count maximizing use of metformin in patients diagnosed with type 2 diabetes and cancer. While use of metformin as an anti-tumor agent is currently tested in a concerning high (cost-wise) number of clinical trials, maximizing its benefit among patients with type 2 diabetes is yet to be a focus despite the drug being the first line therapy.

    What are your thoughts?

  • How should I validate parameters generated by Paramchem?

    Getting high penalty ligand. str generated by Paramchem. The suggestion is to do some validations. What steps are to be done to do these validations?

    Justin Lemkul · University of Maryland, Baltimore

    You've posted this question several times on gmx-users and still haven't really responded with any details when I've asked for them.  What are the terms that have high penalties?  What is the molecule?  Have you gone through the CGenFF tutorial and paper and understood what the parametrization strategy is?

  • Mark Quinlivan asked a question in MDCK Cells:
    Is there an optimum time point (day/hrs) to harvest influenza infected culture supernatant to obtain a high titre for the haemagluttination assay?


    I`m trying to set up the Influenza HI assay in our lab but I`m struggling to get any virus titre on the HA assay.

    I grew up H1N1 \California/07 pdm0  in MDCK cells. On day 3-4 good I saw good CPE. I took an aliquot of the supernatant, spun one down to rid of the debris (9000rpm, 10 mins) and tested another not spun. I tried turkey rbs and human type-0. Neither worked.  I did a crude real-time pcr on my supernatant and got 10e9 copies per ml.

    The inoculum was supplied by a college. He gave me 2x1ml aliquots. When I tested the second aliquot he gave me, without culturing it further it titred well. 

    I`ve checked the media recipe with him and its fine so that's not it. I tried purifying by ultracentrifugation but again nothing.

    I`m going to test supernatant on days1, 2, 3, 4, 5 and 6 post infection. Is it really possible that the virus has lysed somehow and the RT-CTR is detected just RNA floating around In the media?

  • Anne Assunção asked a question in Macrophage:
    Who knows if macrophages express PGC-1alpha? Is there some mice or macrophage knockout para PGC-1 alpha?

    I think all cells express PGC-1 alpha but I don't have sure. 

  • William J. Croft added an answer in Biofeedback:
    What distinguishes HRV Biofeedback from RSA Biofeedback, Respiratory Feedback and Heart Coherence Biofeedback?

    The Terms HRV BF, Heart Coherence BF, Respiratory BF and RSA BF often seem to be used synonymously. However, different authors stress different aspects of the intervention. Furthermore, the best respiratory frequency to increase HRV (around 0,1 Hz) doesn't always seem to be the best frequency for HR/RSA Synchrony/Coherence. Are there clear distinctions?

    And what is the difference in calling the respective Intervention "... Biofeedback" or "... Training"?

    Thank you.

    William J. Croft · Lightfield Systems

    Here's a pdf summarizing HeartMath's Coherence algorithm.

  • Anthony Foris added an answer in 1H-NMR:
    What is the basic difference between 13C-NMR and 1H-NMR in order of their principle and functions?

    Selecting one of the two techniques, what can we expect by using, either it depends on what kind of compounds we have to analyse or something else?

    A few additional comments: In problem solving, a good general rule is to start with the simplest, fastest, most cost-effective tool. In solution NMR of organic compounds, this is 1H NMR, followed by 13C NMR which normally takes longer and may require a more concentrated solution. If one-dimensional NMR techniques do not give you adequate information, then employ 2D methods. If there are additional atoms (e.g., N, S, etc.) in your molecule, multinuclear magnetic resonance will yield further information. I your compound contains fluorine, 19F NMR is also a useful technique. For very small samples or very dilute solutions, cryoprobes may help. All this assumes that the required equipment is available to you. You may want to check out 1D and 2D NMR Experimental Methods - Emory University and/or Structural Elucidation of Small Organic Molecules by 1D, 2D and Multi-Dimensional Solution NMR Spectroscopy on the Internet for a lot more detailed information. If you would like to see an example of complete characterization of a small organic molecule by 1H, 19F, 13C, 15N, and 17O NMR, check out Multinuclear magnetic resonance analysis of 2-(trifluoromethyl)-2-oxazoline (Magn. Reson. Chem. 2005; 43: 867-868). (If you have no access to this publication, I'll be glad to send you a reprint by post.)   

  • Zachary Kiser asked a question in TNF Alpha:
    Concentrating protein in a centrivap?

    I recently performed an ELISA for TNF-alpha using undiluted cell supernatant and my protein concentration was too dilute to get decent results.  Would using a centrivap to concentrate my protein followed by reconstitution in a smaller amount of solvent work help?

  • How can propensity matching score technique maximizes the validity of research? Please describe it with suitable example?

    Propensity matching score technique and its application in research methodology is still unknown for many researchers. 

    Ariel Linden · University of Michigan

    Propensity score (PS) matching (or other PS techniques such weighting, or subclassification) are part of a greater family of causal inferential techniques that try to emulate the randomized controlled trial (RCT) by ensuring that participants and controls are comparable on baseline characteristics. The difference is that RCTs randomize participants and thus groups are assumed to be comparable on both observed and unobserved characteristics. When using PS techniques, participants can only be matched to controls on observed characteristics and we assume that there is no residual confounding.

    I am attaching links to several of my papers on the topic. They provide very specific examples of how these approaches are applied in different contexts.

    I hope this helps


  • John Crowley asked a question in Predators:
    Herd prey reactions to predators (lions) living in close proximity and witnessing predator kills?

    I have been searching for evidence (mostly on Youtube) of herd reactions to lions taking down a herd member.  Are there any descriptions you know of?  I have the impression that when predators have taken prey the herd seems to return to normal behavior largely ignoring the kill and the predators, so long as they are at a certain distance.  Is this so?

  • Critical thinking vs. truth in education?

    Many educators claim critical thinking as one of the major skills for 21st century students. Students may challenge any 'fact' to construct their own body of knowledge. 

    On the other hand, educators have to build on some truths (e.g., in maths we use axioms) in their teaching. This can be overwhelming students. How do you, as a teacher, find the right balance?

    Marcelo Negri Soares · Universidade Nove de Julho

    Critical thinking, because we know the truth by criticizing and getting new awnsers.

  • How can I get a Single crystal for metal complex?

    I have a series of Co(II) complexes with different ligands. I got single crystals of some complexes only. In this series, one complex  shows oily liquid nature after 5days  of recrystallization (Slow evaporation ). I can't able to make it for single crystal at Room temp. or   low temp. (refrigerator). Pl. forward you advice 

    Lucas Bonan Gomes · Universidade Federal do Rio Grande do Sul

    I totally agree with Dr. Tsymbarenko.

  • How can we measure impact of a project to its stakeholders?

    I am involved in evaluating a stakeholder engagement project (Technology ethics) . The aim of the project is to improve respect of ethics principles and laws in technology research and innovation, and to ensure that they are adapted to the evolution of technologies and societal concerns.

    One of the main focus of the evaluation is assessing the impact of the project to stakeholders. However, I am thinking about ways of measuring impact (qualitatively, quantitatively or a mixture of both) therefore any suggestions are welcome. The evaluation will be looking at, for example, stakeholders change in attitudes or behavior  towards technology ethics, evidence of learning, level of  involvement/ engagement during and after the project's life cycle.

    Carole Rushton · Griffith University

    Hi Tilimbe, my response 'ask them' may have seemed glib but was kinda serious too. You could take a more radical approach using libratory participatory action research. As well as asking  'the stakeholders' what impact the program had on them  you might also ask them how they think it should be evaluated.

  • Nikolai I. Kobasko added an answer in Heat Flux:
    Why are critical heat flux densities not widely used when investigating cooling intensities of quenchants?

    The main characteristics of liquid quenchant are critical heat flux densities qcr1 and qcr2. At present, nobody in heat treating industry uses them and doesn't an appropriate standard exist to measure these very important parameters. I'm greatly surprised, why did a such situation appear ?

    Nikolai I. Kobasko · IQ Technologies Inc., Akron, USA and Intensive Technologies Ltd, Kyiv, Ukraine

    Thanks for the attached three interesting papers which I already uploaded. I consider our discussion as a very useful information both for us and readers.

  • John Jupe added an answer in Chimpanzee:
    Have primate species other than Homo sapiens engaged in acts of aesthetic creation?

    For several years some scholars have accepted the engraved pieces of ochre from Blombos cave in South Africa, at least one of which has a geometric cross-hatched pattern, as evidence of early modern human aesthetic creation (ca. 75,000 BC). See: Henshilwood, Christopher S.; d’Errico, Francesco; et al., “Emergence of modern human behavior: Middle Stone Age engravings from South Africa,” in Science, new series, vol. 295, no. 5558, February 15, 2002, pp. 1278-1280 (http://www.sciencemag.org/content/295/5558/1278.abstract?sid=da7c3755-b2bc-4ced-93da-2c024c50b1fd, access: March 14, 2015).

    The recent discovery of similar engravings on shells on Java, from ca. 500,000 BC -that is, long before the emergence of modern Homo sapiens-, suggests that aesthetic creation evolved gradually. See: Joordans, Josephine C. A.; d’Errico, Francesco; et al., “Homo erectus at Trinil on Java used shells for tool production and engraving,” in Nature, December 3, 2014 (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13962.html, access: March 14, 2015).

    Suggestions that chimpanzees make aesthetic decisions while painting are intriguing. See the following texts and video:





    Can anybody point me toward additional studies on aesthetic creation by nonhuman primates, either in the archaeological record or among our contemporary primate cousins?

    John Jupe · Perceptual Awareness Centre

    The left hand view of the flint is the front of the object. This is the face that the individual modelled in aesthetic terms. The Right had view is just the back. it has purpose only.

  • Ni Ge added an answer in Special Relativity:
    When it comes to simultaneity is Einstein correct or is Dingle correct?

    Albert Einstein claimed in 1905 that a single event can occur simultaneously at different times within two inertial reference frames moving relative to one another. In 1950 Herbert Dingle argued that different times cannot be simultaneous. I have analysed this conflict by deriving the Lorentz equations using both points of view. According to this analysis Dingle must be correct. See youtube presentation of this analysis at  https://youtu.be/4XLYzhHQ64Y

    Dear all,

    There is no time dilation. It is a mistake to think there is one. Two referentials will have a time delay because of aberration of light.


    Finally everything is simultaneous, because time is for everybody the same!

  • Md Mazaharul Huq asked a question in Footwear:
    I would like to know the List of Univresity that provides M.Sc or PhD degree in leather or footwear?

    I need a list of university that actually work or do research with leather related work.

  • Ismael Justo added an answer in Mortar:
    What is the percentage of activated carbon that I can add to a mortar mix without compromising compressive strength?

    Considering that the activated carbon will substitute part of the mass of sand of the mix.

    Ismael Justo · University of Colorado at Boulder

    Thank you Martin for your answer!!! and I understand this is not a simple number answer, but your comments give me some light as how to do the first attempts.

    I will be trying with AC from coconut shells, do some lab experiments, and then have some conclusions to be done. I will let you know how it works.

    Thanks again!!

  • What is the condition required for an Electromagnetic Radiation (EM-R) to be produced?

    The “Electromagnetic Radiation Energy and Planck’ Constant” suggested the existence of this constant, what do you think about it?

  • 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

    Thanks, Tausif, for an enlightening article. This is far more prevalent than most people realize. Without a doubt if it kills the animals it is not safe in the long-run for human consumption. We see this same paradigm in animal studies on every single artificial sweetener (Stevia is not artificial and is safe), and in every independent animal study on GMO high fructose, showing that all gain weight and fatty tissue around the heart even in small quantities (contrary to the oft repeated rebuttal by vested interests who would like us to think "the body doesn't know the difference"--it does and we are a sicker people because we tend to ignore this fact).  This applies to so many "approved" food additives and medications that the list is as exhaustive as it is pervasive. Thank you again for bringing this to the discussion.

  • Is operations research the same as operations management?

    Many business schools treat operations management subject equivalent to/to be dominated by operations research techniques. While it is imperative to know the techniques to solve the managerial issues, it is very important for operations management students to dwell more on the business perspectives. I strongly vouch the students from OM background should know more managerial issues to see the usage of the techniques in their professional life. Here, the derivation of algorithm is immaterial where as the appropriateness of the technique matters a lot. I welcome the view points from the academicians and practitioners to have a discussion on this.

    Muhammed Kürşad Özlen · Pamukkale University

    Operations Research is a set of techniques used to support OM functions.

    An Operations Manager does not need to know all these techniques in detail. However, it is good to know the existence of these techniques (how they work, some basic operations) and at least reading the outcomes of  them.

  • Alice Ceacareanu added an answer in Pharmaceutical:
    Is metformin benefit in cancer patients the result of direct tumor-kill?
    Reported to have a distribution volume of 300-500L, metformin would seem to have a wide penetration and retention - fact not necessarily true. Non-diabetes cancer patients receiving metformin after cancer diagnosis (perioperative) had no benefit; however, numerous studies show that metformin had a positive impact on cancer occurrence when taken chronically for type 2 diabetes (a condition otherwise known to increase cancer risk).
    Alice Ceacareanu · University at Buffalo, The State University of New York

    Hi Karen, I will be interested to initiate a discussion about the SCID experiment. We also worked on SCIDs and it was interesting to find out that insulin resistance occurs in high fat fed males, but not females SCIDs. The experiment you mention was done in male or female mice (or both)? What diet were they fed?

  • Wei Chen added an answer in Weka:
    What are the ML methods that are suitable for multi-label classification & how can we apply these methods using WEKA?

    What are the supervised machine learning (ML) methods that are suitable for multi-label classification (i.e., classifying documents where each document might belong to more than one conceptual class) and how can we apply these ML methods using WEKA?

  • Is there any reference about the global prevalence of autism spectrum disorders?

    What is the global prevalence of autism spectrum disorders? Is there any statistics about ASD in developing and developed countries?

    Ahmad Rayan · Zarqa University

    Thank you Dear Nordahl-Hansen

  • Is anyone familiar with MATPOWER, a load flow simulation package??

    I have problem entering the data when a generator is connected to a transformer. any help would be really appreciated!!!

    Apostolos Arsenopoulos · Democritus University of Thrace

    Hi Mostafa,

    I need MATPOWER for my Msc homework so i have to deal with it. If you can help me with my issue i am glad to hear your opinion.