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.

Browse by research topic to find out what others in your field are discussing.

Browse Topics

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
  • What mental exercises you suggest to promote a healthier thinking
    The mental brain health plays an essential role in almost everything we do. How to promote our mental brain health?
    Kamal Bani-Hani · Hashemite University
    Very well said dear Miranda
  • Fusion efficiency of plasma heating vs particle acceleration
    We can obtain the fusion rate by using cross section, ion density and speed. The cross section is calculated using particle accelerators. Heating to 25keV plasma is not the same than throwing ions again a blanket because when heating a plasma, not all the energy is used to accelerate ions again ions but also to make rotations and elastic/non elastic shocks. But when heating the shock rate is increased. My doubt is at the same ion energy level (as example 25keV) what is really the heating efficiency with respect using linear accelerators
  • Murali Poduval added an answer in Trauma Surgery
    I have recently treated an open (Gustilo II) mid shaft clavicle fracture. What would you prefer as a treatment option?
    It was a mid shaft open clavicle fracture associated with scapular neck fracture occurred after attack with an ax or similar tool. The patient also had a serious head injury. At 3 a.m., I intramedullary placed a 20cm long Schantz pin. Fortunately, the main neuro-vascular structures and lung were intact. There are only few articles related to this topic.
    Murali Poduval · Jawaharlal Institute of Postgraduate Medical Education & Research
    Yes Dr Nelson, I agree, but here we have damaged skin already.
  • Gromacs error in equilibration
    i run equilibration using nvt.mdp for 100ps. i get the following error. File input/output error: Cannot write trajectory frame; maybe you are out of disk space? For more information and tips for troubleshooting, please check the GROMACS website at http://www.gromacs.org/Documentation/Errors i have 500gb free space. i dont know where is the error. previously i follow the same protocol for another protein on another computer, i didnt get error. but this time i am using new computer. i need help. i shall be very thankful to all.
    Muhammad Junaid · Abdul Wali Khan University Mardan
    i have cori5 desktop with Linux opensusi operating system. i make a folder with name SIMULATION in home directory. i use this for simulation. i don’t know how to allow total of 500 GB space to this folder. Please help me.i shall be very thankful to you
  • Out of curiousity, is it possible to put two PCR products in one well during gel electrophoresis?
    Two different pcr reactions, one well. Is it possible?
    Kamran Shinwari · Kohat University of Science and Technology
    Do a simple check, if your two pcr products are amplified with two df primers then on agarose gels of df concentrations (eg 1 & 1.5%) check the products separately in dft wells and also mixture of pcr products in same well in both of 1 & 1.5% gels ! (a bit tedious but u will get confirmation of product size variation, if not on 1 gel than on other definitely !
  • Emre Kishali added an answer in Thermal Analysis
    Is there any publication/research regarding thermal performance simulations of historical monuments?
    There are helpful simulation programs in order to evaluate thermal performance of building envelopes. These programs enable the experts to have indoor temperature, RH values etc. easily either in the phase of design or afterwards. On the other hand the approach for the historical buildings is more complicated than new structures. I would like to learn whether historical monuments (especially mosques) are analysed via energyplus, ecotect, designbuilder etc. in order to get thermal performance values.
    Emre Kishali · Kocaeli University
    Thank you Magdelena!
  • i need a solution of ZnCl2 with density 2.1g/l
    How to prepare it?
    Jeremy Rawson · University of Windsor
    Please clarify: do you need a density of 2.1g/L or so you want a concentration of 2.1g/L. I suspect you need the latter which is trivial; take 2.1g of ZnCl2 and make it up to 1.00 L by adding distilled water.
  • What is the best method for making glycerol broth?
    If I want to make glycerol broth for my isolates, what is the best method do that and what are the best proportions of the glycerol and the broth? Please provide a detailed protocol, thanks. Please I need help
  • How to remove/decrease the concentration of nitrate, phosphate and sulfate in basic aqueous solutions?
    Zero-valent iron nanoparticles have the ability to decrease the concentration of nitrate (nitrate will be reduced to nitrite, ammonia, and nitrogen gas), but they are effective in acidic solutions (pH around 3). I'm looking for something that can remove nitrate and phosphate in basic solutions, or at least find a way to use iron particles in basic solutions.
    A.H. Pizarro · Universidad Autónoma de Madrid
    For the elimination of nitrates you could convert into N2 by catalytic reduction using other noble metal catalysts at higher pH. Phosphates and sulphate could be removed by other processes or precipitate them.
  • Nura Umar Kura asked a question in Validation of DRASTIC model
    Can some one explain to me how to do sensitivity analysis and validation of DRASTIC model?
    Like a step by step guide because most of the journals only show results with no details on how to get there
  • Do you think design codes should strictly provide limitation for natural frequency?
    Natural frequency of building structures is one of the most important parameters in seismic design. It affects to building stability and deflection. Design codes normally give limits on story drift and total deflection.
    Julian Carrillo · Nueva Granada Military University
    Please, check section 2 of the following paper:
  • Justin Lemkul added an answer in Gromacs
    How to assess Gromacs results ?
    please , I need any source which discuss gromacs results . I perform ptn-cplx simulation . put as I see I had bad results , so I need to ensure that results is really bad and what can I do to improve the results (i.e that parameters that I can change )
    Justin Lemkul · University of Maryland, Baltimore
    The description is still lacking in any useful information. What are you hoping to observe in the simulation? What defines "bad" - protein unstable, some value from the literature not being reproduced, etc?
  • Taiar Redha added an answer in Applied Ethics
    Should it be ethical to use animals for sports and entertainment?
    Animal rights, Legal aspects. What do you think?
    Taiar Redha · Université de Reims Champagne-Ardenne
    only for horse in my opinion. They have to improve their physiology performance. regards
  • Eric Lord added an answer in General Relativity
    Why is there so much fuss over the twin paradox in General Relativity?
    In the twin paradox, AA is the brother who stays on Earth and BB the traveler who is moving away from the earth, in the rocket. When BB returns, AA thinks that BB is the youngest because the speed of the rocket was almost c. However, BB believes that the Earth is who took away his brother from him and when they are reunited, notes that AA has not aged as much as he. Clearly, if there is no preferred reference frame, they cannot feel a difference in age.
    Eric Lord · Indian Institute of Science
    Jim ~ "What's "special" about special relativity is the postulate that the laws of physics are invariant in all inertial systems" But that's true also in GR! The difference between SR and GR is this: In SR inertial frames are all moving relative to each other with uniform motion in straight lines. In GR inertial frames are in ''free fall'' - when gravity is present there is no such thing as "uniform motion in straight lines" . That concept is replaced by geodesics in curved spacetime.
  • Carla Smalley added an answer in Resilience
    Which is the best instrument to measure social competence in 8 year old children?
    Considering SSRS by Gresham & Elliot, but was wondering what other alternatives are out there?
    Carla Smalley · Kansas Public School
    I use a combination of tools including a home "grown" one. I like the Conners as it has an early childhood component as well as a tool for children seven and above. But as it has been mentioned prior to my joining the conversation, the usefulness of rating scales is limited to what you are measuring. I like conducting interviews and asking questions about social competencies in different settings such as home, school, church and after school programs such as Boys Scouts/Girl Scouts, Boys and Girls Club or daycare. You can get a very skewed picture of a child by looking at only one or two settings thus I use a locally developed interview of social history as well as a functional behavior assessment questionnaire which also identifies the lagging social skills of children. You might try looking up the ALSUP. None of these tools are stand alone measures but in conjunction together they can shine light on social strengths and weaknesses. Another person who has researched in the area of social competencies is Brad Chapin in the realm of self-regulation. He has some VERY USEFUL tools that I use with parents looking for some on the spot helps that work.
  • What is the most popular root for nonlinear algebraic equations that you have faced?
    According to your experience, what number is most frequently obtained as a root using any known method? You can indicate not just one number but an interval.
    Michael Bartholomew-Biggs · University of Hertfordshire
    If we are considering the numerous equations posed as artificial test examples in the literature then zero and one will probably occur pretty frequently!
  • Osama Ghaya asked a question in Gasoline
    Which method should I depend on in my tests; RON or MON gasoline rating ?
    I will do a test on 4 stroke engine (Renault) (gasoline engine) to study its characteristics, and I'm going to use several rating of gasoline; 88 - 9 - 92 - 95 - 98 But there are tow methods to determine the gasoline rating: Research Octane Number & Motor Octane Number So, I will ask the refinery to give me gasoline samples based on one of tow methods.
  • Prashant Chikode added an answer in Laser
    What lasers could be used for Holographic interferometry (HI) and for speckle-interferometry (ESPI)?
    For ESPI application should we use the lasers which are suitable for HI or we can take a laser with lower quality requirements?
    Prashant Chikode · Dept. of Physics, Jayasingpur College, Jayasingpur
    The wavelength of laser is normally dependent on the object you are going to record. 1) For beginners H.I. and E.S.P.I. can be done with normal He-Ne laser with wavelength 20 mw. 2) If you are going to record the further object may be you can use ND-Yag laser
  • Sami Varjo added an answer in Image Processing
    Where must we use variance and mean of image?
    .
    Sami Varjo · University of Oulu
    Depends "quite a lot" on what you are doing, I'd say. Median is a lot of more robust than mean in most of the cases for me. But if you are after speed...
  • Are virtual particles really constantly popping in and out of existence? Can laser make them real?
    Virtual particles are indeed real particles. Quantum theory predicts that every particle spends some time as a combination of other particles in all possible ways. These predictions are very well understood and tested. Quantum mechanics allows, and indeed requires, temporary violations of conservation of energy, so one particle can become a pair of heavier particles (the so-called virtual particles), which quickly rejoin into the original particle as if they had never been there. (see Scientific American, Oct 9 2006, http://www.scientificamerican.com/article/are-virtual-particles-rea/) Recent methods claim that lasers will be able to make virtual particles real: "Next-generation lasers will have the power to create matter by capturing ghostly particles that, according to quantum mechanics, permeate seemingly empty space." The uncertainty principle of quantum mechanics implies that space can never be truly empty. Instead, random fluctuations give birth to a seething cauldron of particles, such as electrons, and their antimatter counterparts, called positrons. These so-called "virtual particles" normally annihilate one another too quickly for us to notice them. But physicists predicted in the 1930s that a very strong electric field would transform virtual particles into real ones that we can observe. The field pushes them in opposite directions because they have opposite electric charges, separating them so that they cannot destroy one another." (see New Scientist 2010,http://www.newscientist.com/article/dn19327-lasers-could-make-virtual-particles-real.html) So do you think that lasers will be able to make virtual particles real? Your comments are welcome.
    Victor Christianto · University of New Mexico
    @Jorge. Thank you for your answer. Does your theory predict how laser can stimulate particle creation? Best wishes
  • What is best method to remove pyridine from a reaction mixture?
    My reaction was performed in pyridine and at the end of the reaction I evaporated the pyridine with co-evaporation by toluene. Then to obtain my cpd (benzoylated sugar) I just worked up (water/ethyl acetate) the organic layer containing my cpd. But on doing TLC the organic layer still contained pyridine showing a tailing on the TLC plate. I want a very convenient method to remove the pyridine because my cpd is an intermediate and should be pure for the next step.
    Thangaraj Devadoss · KVSR Siddhartha College of Pharmaceutical Sciences
    Repeat the toluene co-evaporation process for three to 4 times, it affords the pyridine free compound. If this protocol is failed, use aqueous HCl (if your compound is stable in acidic medium, and no free amine group) in cold condition during work up. This process will furnish your product without pyridine.
  • Mohan Krishna asked a question in Electric Drives
    Hi everyone, Could you please enlighten me on the current research status of sensorless vector control of induction motor drives
    In terms of the control platform used and the speed estimation
  • How can social workers reconcile the principle of confidentiality and duty to protect/report?
    The principle of confidentiality and duty to report/ protect are key principles in social work practice. In the case where a social worker's quest to promote the principle of confidentiality breaches his/her duty to report and vice versa, how can such a social worker address this ethical dilemma?
    Dr. Ubahara Sahayaraj · National Institute of Mental Health and Neuro Sciences
    This is the dilemma each and every Social Work Professional would have come across at least once in life time. I need to know when this Question arises to the Professional (A professional begins a profession, Mid Career Professional or an Expert? What is the issue that would result in..... (is it Life threatening to the other or by breaching (while reporting) what is the effect that would cause to the one who shared with you. It is the professional judgement and the one’s own conviction and integrity to Professional Values. I am not sure what in what context your dilemma arises. If you could give me the incident or narrate the situation with which you encounter with this dilemma we could discuss. You need not mention the Agency you work for or where you encounter this issue, Narrate the incident so that we can discuss. Another way to tackle this issue is through the Principle of Double Effect (a principle – in plain choose the lesser evil, usually used in medical issues like - Pregnancy and abortion – What is your intention and whether your integrity (social work ethics ) is not questioned, to what extent that is going to affect the other and the one who shared ? Whether is there any legal implication attached to it (It depends upon country to country). To my best of my knowledge it is always better to get the consent from the person before you could start the intake that you discuss certain issues like dilemmas with the experts/agencies, which would sort all your issues. Hence you share the responsibility with the experts/ agencies in treating this special issues and it would lead to better discussion than brood over dilemma always...( I am Dr.S.Ubahara Sahayaraj, a Psychiatric Social Worker, completed MSW (2003) from Loyola College, Chennai, India ; M.Phil (Psychiatric Social Work) (2007) and Ph.D (2013) from the Department of Psychiatric Social Work, National Institute of Mental Health and Neuroscience (NIMHANS), Bangalore, India. I worked as a Psychiatric Social Worker for three years at the Department of Psychiatric Social Work, NIMHANS, Bangalore, At Present working at Centre for Addiction Medicine, Department of Psychiatry, NIMHANS, Bangalore, India. When you work with a multi disciplinary team all these issues would be solved, because the discussion is based on a team than by one (You alone). I am ready to discuss further on this issue...
  • Jonathan Edwards added an answer in Philosophy
    Are we ready to understand Leibniz now?
    Three hundred years after the publication of Monadology in 1714, Leibniz's philosophical work remains largely ignored or misunderstood. There are important new developments in commentary from philosophers like Daniel Garber and some of the most serious misinterpretations, like 'psychophysical parallelism' are now being discarded, but there still seems to be very little appreciation of how much Leibniz's work presages modern physics. Leibniz was in many ways first and foremost a theoretical physicist, with his metaphysics being designed to describe that deeper layer of physics that was empirically hard to address and required careful inference. That deeper layer looks extraordinarily like fundamental physics as it is now understood. In this tercentenary year, is it perhaps time that Leibniz's prescience was more widely recognised and a more concerted attempt made to understand what he really meant - which probably bears little or no relation to what people thought he meant for most of the early twentieth century.
    Jonathan Edwards · University College London
    NATURE MAY LOVE TO HIDE BUT CAN BE UNCOVERED BY LOGOS My understanding of Heraclitus is minimal but I suspect he was a bit like Leibniz, in being essentially a dynamist. For Leibniz all that exist are units of force or action. There are no 'objects' with 'intrinsic' natures. The actions are not actions of things, just actions, perceptions, reflections, representations or whatever. Philosophers cling to the idea of intrinsic properties in addition to relational dispositions but Leibniz realised that any such idea of intrinsic properties would be an illusion. Essence is change or process. So, rather than building on Leibniz, Kant in fact fails to understand the main message of Heraclitus and Leibniz. He wants a 'ding an sich' (thing in itself) as well. He realises that such an intrinsic essence would be unknowable because it could not give rise to knowledge through being a relational disposition. But Schopenhauer points out the fallacy of Kant's suggestion. All knowledge is inference of the existence of something. If Kant can infer the existence of a ding an sich then he can know it, even if dimly. So if a ding an sich is really unknowable we cannot infer there is one. And that must be the case. We have no reason to infer that anything has any intrinsic nature. When we ask 'what is it really like' we are normally asking 'what would it be like viewed or sensed another way, or imagined using our ability to construct things in the mind as if we had sensed them (like a unicorn)'. If we ask what the sun is really like the answer may be that it is so hot you could not survive touching it. So 'ding an sich' is 'what something is really like' in a way that we never normally mean - in fact it is in a way that means nothing at all. So everything in the universe is knowable. To be unknowable is a contradiction. You might say that a pebble four hundred light years away is unknowable but this is wrong. It is merely unknowable in the way we are used to by standing next to it and using our eyes. It is perfectly knowable in the way we know things four hundred light years away - rather indistinctly, as Leibniz says. And there are no pebbles unknowable in principle in the sense that if you were near them you could not know them by seeing or touching. So I think what Heraclitus meant was that Nature presents itself to us in a rather oblique way, as if it was made of things, when in fact it is made of flux. But the reasoning of logos can always reveal the truth, even if 'most people never see this truth and even those presented with it for the first time will not see it'. Once we know that all is action, change or flux, then there is nothing that could be known that cannot be known. Knowing is a process of relation by action. Everything in the universe is related to everything else through action so nothing in the universe can be unknowable. It is simply meaningless to suggest so. Schopenhauer rightly realised that knowing our own thoughts was rather different from most knowing, but it is not a knowing of anything intrinsic, as perhaps he concluded and Bertrand Russell also suggested. In our thoughts we know our previous thoughts through memory but there is no reason to think we know our own intrinsic nature. Hume I think was nearer the truth on that. We may be able to infer the dynamics of our own internal actions, but that requires careful philosophical deliberation. It is not just a matter of direct acquaintance.
  • Rajendiran Narayanasamy added an answer:
    What compounds have fluorescence?
    If cyanide has fluorescence and in TLC, is it observable under UV lamp?
    Rajendiran Narayanasamy · Annamalai University
    In general, aromatic compounds or heterocyclic compounds having electron donating or electron withdrawing functional groups are more fluorescent. Further if the molecules having halides or nitro groups diminished or quenched the fluorescence. Please see N.Rajendiran, et al Annamalai University, India, articles or S.K.Dogra et.al IIT Kanpur, India articles.
  • Allah Bakhsh added an answer in Molecular Cloning
    How can i confirm Agrobacterium (GV3101) transformation
    I am facing problems in confirmation of transformed GV3103. Transformed bacteria is able to grow on antibiotic selections media (Rif+Gent+Kan) while the wild type was unable to grow. But colony PCR and PCR on mini preps were negative. What can be the problem???. I tried different concentrations but still the bacteria was able to grow.
    Allah Bakhsh · University of the Punjab
    Strange it is really! Positive is working, colonies are growing well on antibiotics... Why you are going for prep here? Why not colony PCR or broth PCR?? Two things further you can do by the way, change the method of transformation of agro cells. Go for electroporation, rather than heat shock. How much plasmid you are harvesting, check it quality and quantity, make further dilutions of it. It must work.
  • Sami Varjo added an answer in Signal Processing
    What do we mean when we say that the wavelets and their scaling function form a tight frame.
    what is the intuition behind this and what does it signify. I do not have a strong mathematical background but have worked on wavelets as a signal processing tool.I would like to learn the mathematics behind it.
    Sami Varjo · University of Oulu
    To clarify - can the coefficient vectors for a given input be different when the frame is tight as I assume? Only the inverse transformation is still unique...? I.e. the forward transformation may have multiple solutions but the inverse has just one..? Or is it a strict one to one mapping?
  • Is there any non-destructible method to estimate the compressive strength of concrete?
    Compressive strength of concrete is estimated by using UTM/CTM machine by breaking the specimen. Is there any technique by which the specimen remains intact and we can get the compressive strength?
    Julian Carrillo · Nueva Granada Military University
    Attached please find two chapters of the book "Testing of Concrete in Structures". These documents will help you to study the surface hardness methods and ultrasonic pulse velocity methods. Best regards.
  • How can I treat wastewater containing nitrite, ammonium, and ferric ions?
    I have wastewater containing high concentrations of nitrite (2 mM), ammonium (4 mM) and ferric ions (20 mM), along with some organic compounds such as acetic acid and ethanol (COD = 1500 ppm). The pH is around 4 to 4.5. I want to treat the NOx-N and NH4+ - N from the wastewater in order to regenerate the ferric containing water for recycle. What should be the appropriate treatment method (chemical or biological) that can be applied?
    A.H. Pizarro · Universidad Autónoma de Madrid
    Maybe it's better to add H2O2 first to eliminate organic matter and convert NH4 to nitrate and after use catalytic reduction of nitrates.