Q&A

ResearchGate Q&A lets scientists and researchers exchange questions and answers relating to their research expertise, including areas such as techniques and methodologies.

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  • Abbas Rahdar asked a question in Hardness:
    Easy and hard axes in a mono layer in the direction of that?

    Easy and hard axes in a mono layer in the direction of that?

  • Michael Bamidele Soroyewun asked a question in Chennai:
    Can I get the full text of this paper : Detecting and spotting bombs using wireless sensors and expert systems?

    This paper is written by the following authors

    Prabhakaran, S.
    Dept. of IT, Hindustan Univ., Chennai, India
    Sharon Rosy, S. ; Shakena Grace, S.

    And other recent researches on explosive detection with expert systems

  • Javier Gordon Ogembo added an answer in KSHV:
    Does someone have anti KSHV gH or gH antibodies for immunoblot?

    I am in need of anti KSHV gH and gL antibodies. Does anyone knows a commercial source or lab which has these Abs specific for immunoblot or cytometry

    Javier Gordon Ogembo · University of Massachusetts Medical School

    Thanks Vincent, I will definitely try them. 

  • Islam Hamim asked a question in Plant Pathology:
    Can anyone explain dual culture for virus isolation?

    virus, plant pathology, biology, botany, agriculture

  • Todd Reeves asked a question in Peer Review:
    Is anyone aware of an existing peer-reviewed, systematic review of online learner interaction self-report measures?

    Such a paper would review these instruments in terms of construct(s) purportedly measured, extant reliability and validity evidence, etc...  Many thanks in advance for your help.

  • Does anyone have some good reference material for Hepatic Stellate Cell cultures?

    I am working with some Hepatic Stellate Cells (HSCs), but I need some more information on culture maintenance, materials for optimal growth, etc. I have read several papers, but I was wondering if anyone knew of a book that provided a good overview for culturing hepatic tissues.

    Thanks for the help.

    Joseph Gosnell · Liberty University

    Thanks, Dr. Jiroutova. I'll send you a message soon.

  • Are you interested in contribute for a topic in Frontiers in Microbiology about microbial metabolism and synthetic biology?

    Looking for contributors in the area of microbial metabolism and synthetic biology for a research topic in Frontiers in Microbiology. Be free to share with your colleagues and partners.

    http://journal.frontiersin.org/ResearchTopic/3237

  • Muhammad Imran added an answer in Coal:
    Has anyone has work on the Solid Coal or Coal Powder using air gasification?

    How much amount of practical Air using solid coal and powder coal down gasifier?

    Muhammad Imran · Underground Coal Gasification Thar Coal Project, Islamkot, Tharparkar, Pakistan

    Dear Saravanakumar A ,

    The requirement of Air/ O2 depends upon the type of Coal ultimate analysis of Coal.

    So the requirements of Air/O2 will be vary from Lignite to Anthracite Coal.

    Regards.

  • What is the probable antibacterial mechanism for essential oil?
    I tested antibacterial activity of essential oil. It showed higher activity against gram negative. Can anyone suggest the probable mechanism?
    B.R. Rajeswara Rao · Central Institute of Medicinal and Aromatic Plants

    I am attaching some reviews on the biological activities of essential oils. Read them and they answer your question.

  • Tausif Alam added an answer in Cognitive Systems:
    Is Chalmers' so-called "hard problem" in consciousness real?

    In his 2014 book "Consciousness and the Brain: Deciphering How the Brain Codes Our Thoughts" Stanislas Dehaene wrote "Chalmers, a philosopher of the University of Arizona, is famous for introducing a distinction between the easy and the hard problems. The easy problem of consciousness, he argues, consists in explaining the many functions of the brain: how do we recognize a face, a word, or a landscape? How do we extract information form the senses and use it to guide our behavior? How do we generate sentences to describe what we feel?

    “Although all these questions are associated with consciousness,” Chalmers argues, “they all concern the objective mechanisms of the cognitive system, and consequently, we have every reason to expect that continued work in cognitive psychology and neuroscience will answer them. By contrast the hard problem is the “question of how physical processes in the brain give rise to subjective experience … the way things feel for the subject. When we see for example, we experience visual sensations, such as that of vivid blue. Or think of the ineffable sound of a distant oboe, the agony of an intense pain, the sparkle of happiness or the meditative quality of a moment lost in thought … It is these phenomena that poses the real mystery of the mind”."

    Stanislas Dehaene's opinion is "that Chalmers swapped the labels: it is the “easy” problem that is hard, while the “hard” problem just seems hard because it engages ill-defined intuitions. Once our intuition is educated by cognitive neuroscience and computer simulations, Chalmers’ “hard problem” will evaporate".

    Personally, I agree with Stanislas Dehaene's opinion.

    Tausif Alam · University of Wisconsin–Madison

    Ursula, thank you. I appreciate your candid answers.

    "I try my very best to be as clear as I can! I don’t try to “hide” any information that I have, in order to impress anybody! I just can’t do better. Read also my answer to Marc that follows later."

    About the above, I think that you misunderstood my intent (or perhaps I did not make myself clear enough). It wasn't your comment that was unclear. I was regretting not having made it clear to you that I do understand the principles of holography (some Physics and Math etc) adequately enough to follow along your proposed model of memory. Had I stated so explicitly, perhaps you would have saved some of your time in elaborating the background... but no major harm done.

    I realize that some times what I think is obvious in my comments must seem cryptic to you (and others). The comment about my inability to fully understand some of the complexities of quantum mechanics was simply to illustrate limitations of my intuitive mind - not that I do not follow their reasoning and the math behind it. My comment about QM was not intended to imply that your model uses these principles heavily (I have read your essay) - it was to let you know, a priori, my own limitations or biases.

    "What you write here, is too far away from my model. I am not able to translate it – with an affordable effort – into the language of the metaphors I am familiar with! Sorry! Maybe you really have a look on synergetics and self-organization!?"

    To begin with, let me be clear that I have absolutely no issues in comprehending what you stated in your essay. However, since any model which closely represents the reality must be able to account for all possibilities that the object/organ in question normally encounters, I am not convinced that this model, as it stands, nearly satisfactorily passes that criteria.

    I often tend to compare normal and abnormal situations to assess how well a model will hold up. In response to one of my questions you refer to "synergetics and self-organization", I am aware of these principles; the extent to which they are applicable ought to be similar in normal conditions as well as when the organ is under compression (referring to my previously raised point). You are essentially advocating a fixed system in 3D, how would it maintain the identical fields/wave-interference patterns when forced to stretch or compress? It is a simple and obvious first test for its validity. From the perspective of pure physics, it is a simple problem to fix (up to a point) by making compensatory corrections (in simple photographic analogy, think of perspective control). Your model relies on waves from multiple sources (action potential rates with a specific periodicity, repeating patterns of chemical flow etc), compensatory actions will necessitate changes in many of these "originators" of wave patterns to arrive at the resultant pattern that matches the original, which will entail retaining sufficient information on relative positions of all the elements that are involved in creating the pattern (also under the same stress). One would think that such changes will be obvious enough to be detectable but I know of no such reports (not to say that they are not there) and I would like to see them as a supportive material.

    I must confess that at some level, the notion that a slice of time and experience can be physically stored in a holograph like condensed form is attractive but in my view it becomes very tricky at the level of substrate, as to how it can be sustained - especially because you are also invoking a dispersed storage system.   

  • Eduardo Brambila asked a question in RNA:
    What is the best protocol to isolate RNA from skin samples?

    Samples are obtained from rat abdominal region

  • What is the effect of heavy metals on soil EC (electrical conductivity) during Phytoremediation process?

    During phytoremediation of heavy metals in pot culture, what will be the effect on soil EC (Electrical conductivity). Its increased or decresed afetr phytoremediation

    Franco Ajmone Marsan · Università degli Studi di Torino

    If I understood your question correctly there will be virtually no change in EC, as it is controlled by cations and anions which are more soluble than HM by far

  • Maha Mohy asked a question in Feature Extraction:
    Shape feature extraction ?

    Hello everybody,
    can you help me in finding a simple and easy to understand illustration for shape feature extraction ,as i am a pre-master student and i got confused of all the high-level papers and surveys which include not explained functions and terms.
    Much thanks for you

  • Does intracellular digestion of larger food particles (like it can be found in bivalvia) occur in teleost?

    I am especially interested in ingested particles of a particle size from 1 to 10 μm. Are food particles of this size range normally processed by intracellular digestion in teleosts?

    Tim Dominik Katzenberger · The University of York

    Dear Vincent,

    Many thanks for your helpful answer. Regarding the 1 - 10µm sized particles; I am aware that food particles of this size are not part of a predative teleosts diet (I think my question was not very well formulated regarding this). I was more thinking of an indirect ingestion via the prey (e.g. ingestion of a small filter feeding invertebrate) that had previously ingested the solid particles (like plastic spheres) itself. These particles will then become available to interact with the digestive system during the digestion of the ingested food and (this is where my question came up) may be possibly taken up for intracellular digestion.

    Many thanks again for your answer.

  • Ricardo Dantas de Lucas added an answer in Exercise:
    Are there some article to learn how change the VO2 kinetics with exercise?

    I want to learn how observe changes in VO2 kinetics during exercise and how extract dates.

    Ricardo Dantas de Lucas · Federal University of Santa Catarina

    The second one

  • Saeid Davazdahemami added an answer in Stress:
    Do you believe all active substances increase in stress conditions?

    we have some examples which indicate active substances( percentage and yield/m2) increase in normal condition., but generally, active substances are increased under stress condition.

    Saeid Davazdahemami · Research Institute of Forests and Rangelands

    dear Nikola, i can't understand what you said.

  • Shovon Lal Sarkar added an answer in Bacteria:
    How do I distinguish and determine species from potentially two different bacteria if their basic morphological features look the same?

    For example, two different species of coccus in mixed culture. How would I be able to determine their respective names?

    Shovon Lal Sarkar · Jessore Science & Technology University

    I think molecular analysis by PCR is the best decision which will precisely help you to distinguish your microbes. Otherwise many false positive result may arise...

  • Fikrat Hassan added an answer in Phycocyanin:
    Any idea about the highest phycocyanin content in spirulina ?

    Have you ever seen phycocyanin content higher than 20% (w/w) and what about the C/N ratio to improve its synthesis ?

    Thanks in advance for yours answers

    Fikrat Hassan · University of Baghdad

    I agree with Jean-Francois Sassi, that the contents of Phycocynain  not depend on C/N.

  • Does anybody have idea regarding how to measure the Impact of Technology on HR Practices?

    Hi, 

    I am trying to conduct a research on impact of technology on HR practices. I have selected three HR practices namely i. recruitment, performance appraisal and training. But I am struck on the point to apply statistic for showing Impact of technology on HR practices. Please help me out. Thank you in advance 

    José Sánchez-Alarcos · Instituto de Empresa SL

    I understand that you don't mean the internal management of a HR Dept. but the impact in the HR management of a company. If  i've got the right intention in the question, I hope this link can be useful for you:

    http://factorhumano.org/2014/03/27/frederick-w-taylor-xxi-century-release/

  • Xiao-Yun Lu added an answer in MIMO Systems:
    How can one determine if a decentralized control is applicable to a certain MIMO system?

    For the simplicity and convenience of the analysis of the MIMO system I want to decentralize the system into SISO systems.
    But the confusion is, how can I  know, if it is applicable or not? In simple words, the analysis for SISO systems will be as reliable as of the whole MIMO system.
    suppose,G=[g11,g12;g21,g22;];

    If I analyse g11,g12,g22,g21 separately then can I give  a conclusion for the whole system G?

    Any help will be highly appreciated

    Xiao-Yun Lu · University of California, Berkeley

    You cannot do it in general even for linear time invariant control system. For some linear time invariant system, you might be able to find a coordinate transformation of the state variables to diagonalize the system with synthetic control variables (due to transformation) if some conditions are satisfied. For nonlinear systems, there is no such way in general. But for some special non-linearity, you may find a nonlinear state transformation to do that.

  • Riccardo Metraglia added an answer in Multimodality:
    Is anyone using graphic novels or comics in classroom-based research?
    This forms part of a wider debate on using youth popular texts in educational contexts. We need to know more about the ways in which using these texts builds on and extends students' literacies.
    Riccardo Metraglia · Università degli Studi di Brescia

    I made a research on the use of webcomics (graphic novels) in weaker students' motivation in engineering education. I found them a proficient way to better motivate weaker students to arouse and keep their attention at a high level during engineering graphics lessons. 

    I hope it can help you.

    Riccardo

  • Ian Robertson added an answer in Hypertension:
    Is it possible to create a hypertension model with rats?

    I want to check one plant extract, how much is it effective in case of hypertension. But I don't want to create obesity induced hypertension. Is there any other way to create hypertension model?

    Ian Robertson · University of Alberta

    Another model available is the infusion of mice with angiotensin II. This can be done by the subcutaneous implantation of an osmotic pump that slowly releases angiotensin II.

  • Are there any alternatives to macromodel traffic simulator AIMSUN?

    My aim is to model traffic in network scale and extract parameters like (Traffic flow, Speed,....)

    Amr Rashad ahmed Abdullatif · Università degli Studi di Genova

    Hello,

    Thanks Luc Dekoninck for your answer. 

    The second opensource name is Cos-Sim

    Greeting,

    Amr

  • What is the alternative test of Chi-square, if there exist many cells have expected frequency less than 5. ?

    Chi-square is a statistical test commonly used to compare observed data with data we would expect to obtain according to a specific hypothesis. If we have two categorical variables both of them have 3 levels  and the (33.3%) have expected count less than 5, so the result of chi-squared test will not be accurate. What is the alternative test? 

    Daniel McNeish · University of Maryland, College Park

    The traditional Fisher's exact test is only computationally realistic for 2 x 2 tables, but the Freeman-Halton extension to Fisher's test generalizes to tables larger than 2 x 2 and takes seconds to compute. The two links I posted above calculate Fisher's test using the Freeman-Halton extension for 3 x 3 tables and returns p-values almost instantaneously. 

  • Daniel Ivanusic added an answer in Yeast Two-Hybrid:
    How can I check quality of Salmon sperm SS DNA?

    I was making the solution of SS DNA. During this I have to sonicate to make working solution. This solution is not working for yeast two hybrid. I have changed all the yeast strain, DNA and medium but still I didnt get the result this time with same protocol (That I used earlier). So can any body suggest me to check the quality of SS DNA, or any other remedies for this problem.

  • What is an easy and accurate method for total and reducing sugars in molasses?

    Hello everyone, 

    I would like to measure the total and reducing sugars in molasses.

    Does anyone know an easy and accurate method?

    Thanks

    Anna Flavia de Souza Silva · Escola Superior de Agricultura "Luiz de Queiroz"

    Hello,

    DNS is commum one for rapid tests, but there's no publication using it due to the errors it can happen in this test with molasses. You will not find good results neither repetitive ones. I worked with this last year and I know the dificulties. Just to add, with every food matrix with dark colors were like that (coffee, molasses, sugarcane juice etc).
    All of this information were already studied and also measured. I have the reference work of it, if you want.

    So, I suggest you to apply Lane Eynnon method. This is the most secure and accurate for want you desire.
    Good Luck!

  • Alan Mead added an answer in Personality Traits:
    What questionnaire can I use to measure level of conscientiousness?

    I am looking for a questionnaire testing level of conscientiousness (Big five trait) in a dutch adult population. Because I only need to know the level of conscientiousness and because there are time constraints, I prefer a questionnaire that only addresses this factor. Do you have any suggestions? (In English or Dutch)

    Is it possible to just ask only those questions related to conscientiousness from a larger questionnaire?

    Alan Mead · Talent Algorithms Inc.

    Lew Goldberg (one of the main proponents of the "Big 5") has a pool of free items here:

    http://ipip.ori.org/new2413Items.htm

    About 750 of them (most of the items with "H" identifiers above) started life in Dutch:

    http://ipip.ori.org/newItemTranslations.htm . 

    Goldberg has also provided widely-used marker scales for the Big 5:

    http://ipip.ori.org/New_IPIP-50-item-scale.htm

    The (items marked 3+ and 3- are conscientiousness items).  The IPIP items are intentionally simple to facilitate translation. Shortened versions of this scale have been published, I think the shortest had just a couple items on it.

    The main advantage of the IPIP is that you can freely use these items.  In comparison, you are extremely unlikely to get permission to use items from an instrument like the NEO and using them without permission is illegal in almost all countries.

    Another advantage of the IPIP marker scales over, say, the NEO, is that the IPIP markers were produce by Lew Goldberg.  The NEO was a three-factor instrument retro-fitted to a five factor model (that's why it's the NEO instead of the NEOAC), but you could legitimately call Goldberg the "father" of the Big Five (although Jack Digman, Goldberg's advisor Norman, and many others were involved).  I guess my point is that the NEO encapsulates a five factor model, whereas Goldberg's marker scales measure  the big five model.

    Finally, your second question asked about administering only the conscientiousness items.  Goldberg (1992) administered a predecessor adjective checklist in two formats: with all items grouped together by dimension and with all items mixed together.  He didn't find big differences. I think you could argue that justifies using the conscientiousness items by themselves.

    Goldberg, L. R. (1992). The development of markers for the Big-Five factor structure. Psychological Assessment, 4, 26-42.

  • Bouraoui Ilahi added an answer in FDM:
    Did anyone work on 1D Drift Diffusion Model for Crystalline Solar Cells ?

    I was wondering if anyone has ever worked on Drift Diffusion Model for Crystalline Solar Cells finite element analysis on python. I am trying to write the code to do that and I am seeking for some help.

    Bouraoui Ilahi · King Saud University

     A COMSOL Tutorial in this issue is available freely in the web

  • Does SIAR/MixSiar need a correction in the consumer's stable isotope data relative to the trophic level?

    I want to describe a complex trophic web with primary and secondary consumers and different sources using carbon and nitrogen stables isotopes. Do I need to subtract the trophic fractionation for the secondary consumers, or I can just put in the model the raw data for both carbon and nitrogen isotopes?

    Valentina Costa · Università degli studi di Palermo

    Dear Jean-Michel, 

    Thank you to your opinion/suggestion. We will try to split the dataset and to use separate trophic enrichment factor for primary and secondary consumers, but how to deal with intermediate consumers?

    And of course, I agree with you that a deep knowledge of the trophic web is necessary before to use mixing models.

    Merci.