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

  • Alastair Bain McDonald added an answer in Climate Change:
    Are there authentic published work confidently pinpointing the sole anthropogenic factors contributing to Climate Change?

    Combined natural and anthropogenic factors (geologically recent phenomenon) govern Climate Change. It is, therefore, of paramount importance to discretely recognize the role of humans in Climate Change and to plan efficient strategy to mitigate it.

    Alastair Bain McDonald


    The overzealous scientist I was referring to was Copley of your first reference. It is here: https://www.researchgate.net/profile/Jeffrey_Kargel/publication/41173786_Tracking_the_Source_of_Glacier_Misinformation/links/0912f50db974e4051b000000.pdf

    It says : "A bibliographic search suggests that the second WG-II sentence is copied inaccurately from (8), in which the predicted date for shrinkage of the world total from 500,000 to 100,000 km2 is 2350, not 2035."

  • Amaechi J. Anyaegbunam added an answer in Chemical Oxygen Demand :
    If I were to estimate Biological oxygen deman and chemical oxygen demand of estuary what should be the range?

    Can COD levels be too high?? are these High values are due to interference?

    Amaechi J. Anyaegbunam

    Dear Deepthi Hebbale

    Have you studied the river with respect to industries located upstream of the sampling point. In the developing world factories discharge untreated waste into rivers hence the COD should be high in the vicinity of the discharge points. Due to advection and spreading out the concentration of the ions in the water would diminish at great distances from the entry point.   

  • Wilfried Musterle added an answer in Consciousness:
    Is consciousness giving human beings an evolutionary advantage?
    While having the concept of Self as opposed to others or to the environment seems good for focusing the organism functions on survivability and on DNA spreading, is there any evidence that consciousness has an evolutionary advantage?

    To elaborate further, here I'm talking about consciousness as the first person experience. And for "first person experience" I'm not talking about "experience OF first person": conversly, I'm specifically addressing the "experience IN first person MODALITY" (as a corollary to this question, I'm proposing that the word "consciousness" refers to too many concepts). In this view, I consider self-consciousness "experience of first person in first person modality".
    If we embrace the assumption that consciousness is always consciousness of something, we still lack an explanation for the nature and the purpose ("what is/what's for" rather than "how is it") of the first person experience, and as such why evolution favored it.

    In a lot of other Q/A about self and consciousness people are talking about consctructs that may function even without consciousness. Two examples:
    -self: a neural network comprising semantic concepts about the world could very well include the concept of self as a non-other or non-environment, or even a concept of self as an independent organism with such and such features; why do we need consciousness to conceptualize it? Would a machine decoding all the concepts coming across the node of (or the distributed knowledge about) self be considered conscious? We do not have to attribute consciousness to the machine to explain the machine processing its concept of self.
    -thinking: processing is certainly different from consciously elaborate something, as all the studies on automatic and subconscious processing show. On the other hand, this point address the free will problem: when we consciously elaborate something, does it mean we are voluntarly doing so? Or are we just experiencing a first person "show" of something already happened subconsciously (as Libet's studies suggest)? Without touching upon the ad infinitum regression problems, this poses the question if consciousness is useful without free will: if the conscious experience is just a screen on which things are projected, no free will is needed and thus what's the whole point of consciousness? As such, do we also need free will for accepting consciousness? If we are working with the least number of assumptions, it seems unlikely the we can accept consciousness.

    It seems to me that the general attitude of cognitive theories in a biological information processing/computational theory of mind framework is to try to explain everything without putting consciousness in the equation. And indeed it seems to me that no one is actually putting consciousness in the equation, when explaining cognition or behaviour (at least in modern times).

    All in all, it seems to me that all the above reasonings bring the suggestion that consciousness is not needed and has no evolutionary advantage over automatic non-conscious entities. Or that we should make more and more assumptions (such as accepting free will) to make sense of consciousness.
    I think that asking why we have consciousness could lead us to understand it better.
    Wilfried Musterle


    information is only represented and stored in structures of matter or electromagnetic waves but does not exist as mystical something in a speculated "other spacetime".

    This is an interesting idea but not provable by experiments. 

  • Abdallh Dwekat asked a question in Yellow:
    Bacteria on XLD are yellow with black center but after sub culture are yellow without black center what the matter and what i muste do???

    i isolated salmonella from vegetable and water after enrichment the sample on XLD agar the suspected colony are yellow with black center but after sub culture the bacteria are yellow without black center can any body tell me what hap and what i must do ????? thanx

  • Jakob Bruhl added an answer in Technology Education:
    What experience have you had with student generated learning tools?

    I'm interested in making more use of technology in education and one recent idea is to create an assignment requiring students to generate learning tools such as short instructional videos, explanations of problem solutions, analogies or metaphors for course topics. These would be assigned early in the course so students could think about options but would not be due until the end of the course as part of the course review. After vetting by the instructor(s), these learning tools would then be made available to the rest of the students in the course to use in their review for final exams. From an initial literature review, it is clear that this is not a new idea, so I'm interested in hearing more about your experiences with such a concept - the good, the bad, and the ugly!  Thanks!

    Jakob Bruhl

    Thank you for the specific examples. The video ideas and the on-line and other software examples are helpful. I particularly like the point about the resourcefulness and creativity of our students - I do not want to unnecessarily bound them in this assignment because I'm certain they will come up with ideas that I wouldn't.

    Your comment about the value of writing, Vevakandand, is another subject I'm working to integrate more effectively into our technical courses. I'll have to take a look at the book you mentioned, "How Learning Works." Thanks for the recommendation.

  • Vatsala Sharma added an answer in Cognitive Radio Networks:
    I am doing research in Cognitive radio networks. Is there any work done to combine the two spectrum access approaches Underlay and overlay?

    Is there any research paper or thesis in which both the spectrum underlay and spectrum overlay techniques are implemented in cognitive radio network.

    Vatsala Sharma

    Thanks a lot sir saleem for your help. 

  • Francis Steven Mickus added an answer in Art:
    Do we need any definition of Art?

    I´am wondering if we need any kind of definition of Art. In the last period of time, the Fine Art lack any boundaries, or rather should I say any bounderies that couldn´t be falsified. For example if some artist make sincerely a piece of Art and react on something, and some years later, somebody else make something simmilar but inspired only by succes of the first artist and we recognise him, is the second artist also real artist and maker of Fine Art? So I think, there should be some ground rules, and we couldn´t just agree with everything. What I am trying to say, is that despite the overcome normativity in art there should be some rules.

    Francis Steven Mickus


    You are still ignoring the correlary questions which are, i think at the heart of the matter.

    For one thing, creating a jug is not mindless and automated, be it the thousandth jug or the first. have you ever walked into a potter's shop? What is mindless and debilitating is when the constructive process is reduced to a mere unintelligeble fraction of the whole process, although there may be even great value for the worker even in such cases, even if the work is not artistic.

    Repitition does not reduce the intrinsic quality of each jug. just look at our own awe when we find old Roman everyday crockery. but we are losing the mark here.

    My point being that art is the creative process. a work of art is the product of taht process. We do not look at all thes object as such, but that is what they are. not all art has aesthetic objectives, but rather functional objectives, such as the jug maker. But even today, there is much art that is not seen as such. Look at the elegance of teh functionality of this very site where we are having this discussion. thi,nk of the creative input from the programmers and web designers that made this site happen. It is not a thing of beauty, yet is is an artistic creation.

    And it is even derivative, as it bases much of its structure on other social media such as Facebook. But the very adaptations the programmers brought to our needs makes it innovative.

    The 'wave of resonnace', just as the flippant disregard of manual labor in your comment is merely the Romantic and, I daresay Bourgeois elitism that tries to circumscribe art in only  intellectual an aestetic categories that only the enlightened can appreciate.

    This does not preclude the need to offer a defintion for art, quite on the contrary. by offering a definition, you give an idea form and through form meaning. Definitions always change as the needs change, but that doesn't meen that at a given time  and place the definition is valid. it allows all to discuss the same ideaq and give them consistency.

    To refuse a definition for such a great and wondrous activity as art is to refuse its very existence, and therefore reduce it to triviality. If art is only what I say it is, then it is nothing at all.

  • Fatemeh Sepehr added an answer in Solvent Effect:
    How effective are the optimization (and sadpoint) searchs with solvent effects to give good results compared to the vacuum models?

    Hello there noble science people...

    i am doing equilibrium geometries and saddle point searchs in gaseous phases. but the experiments in which the mechanism were based, used polar solvent and the substances involved were charged particles (although closed shell species).

    does this mean i have to emulate these solvent effects for better elucidation and results ? or it'll just make calculation more expensive with little positive gain.

    if so,,, is the PCM compatible with geometry and sadsearch? or is there any other alternative approach?

    Thank you all. Live long and prosper. 

    Fatemeh Sepehr

    Dear Ben,

    C-PCM stands for Conductor-like PCM. It assumes that the solvent has an infinite dielectric constant and is suitable for highly polar solvents. CPCM will do poorly for non-polar solvents. You may find more information in the following paper:

    There they quote: "One can see that PCM and C-PCM solvation free energies are practically identical in water, while the agreement is poorer in CCl4, as expected because the conductor picture is weaker for less polar solvents".

    Hope this helps.



  • Ismaila Aliyu added an answer in Nanotechnology:
    What is the melting point of graphene and graphene oxide?
    Meling point of graphene.
    Ismaila Aliyu

    what about graphene oxide meting point

  • Carolina Alejandra Rojas asked a question in Chile:
    Análisis de Densidad en Santiago de Chile?

    Santiago de Chile

  • Fatemeh Makouei asked a question in Biomedical Optics:
    I have faced a fundamental question! what is the main reason for using FBGs in fiber optic sensors?

    Why the step index fiber with its simple structure is less considered in practical fiber optic sensors?! I have regarded the biomedical optical sensors and I have seen FBGs the most. I was wondering if there is a special reason that this structure is focused.

  • Emil Berengut added an answer in Back Pain:
    Does posture directly effect or improve back pain?

    Any papers or research would be beneficial. Thank you. 

    Emil Berengut

    @Tanchev-completely agree with you on the choice of intervention for adolescents and also adults with non-specific back pain. I am just not sure there's a causal or even a correlative relationship between back pain and posture. It appears that there's quite a bit of redundancy built into the mechanical system which allows for a whole range of postural deviation. I believe that the therapeutic effect of exercise is from 1. Normalizing physical activity 2. General strengthening of most muscle groups, not just the back muscles-as back muscles are active in many movements 3. Decreasing muscle spasm/guarding as the result of inactivity. 4. Improving pain perception and processing. I would love to see evidence which demonstrates on human subjects 1. causation of low back pain by a particular posture 2. better efficacy of postural exercises over any other kind of exercise/intervention for improving low back pain.

  • Shuai He asked a question in Molecular Simulation:
    How to remove the heat generated by external force in MD?

    I want to simulate the transport diffusivity coefficient of a gas in a porous media by using boundary-driven non-equilibrium molecular simulation (BD-NEMD). However, the fluid temperature will increase by the work done by the external force. How can I remove the heat? Will traditional NVT ensemble affect the dynamics properties in such system?

  • Abdelhalim Zekry added an answer in Electronics and Communication Engineering:
    Anyone familiar with Dual Polarized MSK Transmission and Receiver System?

    Dear All,
    I am trying to realize the Dual polarized MSK based optical transmission and receiver system for high data rate (100 Gbps). Upto the transmission level, I am getting spectrum is as per expectations, however at the receiver end, using coherent detector, I am getting the signal points in one coordinate per polarization only, however it should be in four coordinates. Moreover, eye diagram is also not showing as per expectations. Kindly help in finding the fault in logic if any. 
    Thanks in advanced.

    Abdelhalim Zekry

    The constellation diagrams which i see is for 8 QPSK + 2- lvel PAM for both polarization. Th receiver signal is a distorted and noised signal of the transmitted signal in addition to an I and Q, DC shifts. If you reduce the distortion and noise and remove the DC shifts the two constellations will be the same.

    wish you success.

  • Tshilidzi Mukhudwane added an answer in Plant Taxonomy:
    Can any one help to identify this Riccia species ?

    I have recived this material from Kakatiya university campus, Warangal

    + 1 more attachment

    Tshilidzi Mukhudwane

    i think it might be Riccia fluitans

  • Giovani Gozzi asked a question in Gas:
    How measure temperatures with 100 microsecond aquisition rate?

    I intend perform mesurements in ideal gas systems.

  • Jehad Yamin asked a question in Metal Hydrides:
    Has anyone tried the "FlexPDE" software to simulate the heat and mas transfer in metal hydride in 2-D form?

    I am trying to simulate the process of hydrogen storage in Metal Hydride using the FlexPDE software. I am getting strange results. Has anybody tried to solve this problem using this software.

    I do not have access to COMSOL or ANSYS.

  • Joyce Nunez Gary added an answer in Cultural Competency:
    What are effective instruments to measure the level of cultural competence among doctors?

    I need to identify effective tools preferably in survey form to assess the cultural competence level of a group of physicians in a diverse community.

    Joyce Nunez Gary

    Thank you all for your comments and feedback. I have looked at all links provided and continue to make headway while working on my dissertation. I am reviewing Campinha-Bacote's Inventory for Assessing the Process of Cultural Competence Among Healthcare Professionals-Revised (IAPCC-R) and a demographic data instrument.

    Loved " The Clash of Civilization" highly recomended for those that have not read.

  • Mikayel Aznauryan added an answer in UV-Visible Spectroscopy:
    Can anyone suggest how to have my cuvette completely sealed to prevent solvent evaporation during temperature dependence fluorescence measurements?

    I have already a polyethylene lid which is not efficient. I tried to use parafilm but the solvent still evaporates. I tried to put Aluminum foil then the lid on to make it a quick fit, but the solvent still evaporates.

    Mikayel Aznauryan

    Add a bit of mineral oil e.g. from Sigma on top of your sample in the cuvette.

  • Zahra Aslani added an answer in Directed Acyclic Graph:
    In RPL protocol, Does a node generate a DIO message after rank recalculation or wait for trickle timer?

    In RPL (Routing Protocol for Low Power and Lossy Networks), to maintain a DAG (Directed Acyclic Graphs), each node periodically generates DIO messages triggered by the trickle timer.

    If the rank value of a node has changed after recalculation (due to update of ETX after data transmission), does the node issue a DIO message to broadcast the updated rank immediately or waiting for the trickle timer?

    Zahra Aslani

    Thank you very much for your response Dr. Piroddi.

  • Sandeep Lal asked a question in Onions:
    What is the optimum duration and concentration of PEG 6000 and KNO3 for effective seed priming treatments in onion?

    There are several reports available on the effectiveness of PEG and KNO3 in seed quality enhancement with respect to rapid and uniform seedling emergence in onion. However, I need the information/ protocol regarding optimum duration and concentration of PEG 6000 and KNO3 for seed priming.

  • Ricardo S Cardoso added an answer in Coastal Ecology:
    Does anyone know about the effects of sand color on beach resident fauna?

    While I can find good references for dynamics related to substrate size - community or species on sandy beaches, I would like to find more about potential effects of substrate color (which is finally due to its composition).

    Even at temperate latitudes, darker color means higher temperatures under the same radiation. Is there any reported effect of this on life-history traits, or some kind of experiment to test differences in behaviour/physiology of resident species?

    Thank you

    Ricardo S Cardoso

    I believe that this paper can help:

    Biological Joumal of the Linnean Society (1997), 62: 475- 494. 
    Massive polymorphism and natural selection in Donacilla cornea (Poli, 1791) (Bivalvia : Mesodesmatidae)

  • Blake A. Gentry added an answer in Indigenous People:
    How do we explain the origin of private property in land?

    Demsetz bases his theory of private property formation on the anthropology of Canadian indigenes near Quebec during the fur trade.  He claims that soaring prices for furs stimulated the local indigenous peoples to form territories so they could more effectively husband their fur resources (mostly beaver populations).  My question is twofold:  (1) Did contact with the French devastate the indigenous populations as was the case further south, in both North and South American; and (2) did the privatization of the resource (in landed property) lead to local animal extinctions due to intense market pressure for furs?

    Blake A. Gentry

    Correction on previous entry. Jesuits were in the Americas until 1767, having entered in Brazil in 1549. After 1767 Franciscans took over the missions under the Spanish Crown.

  • Zahra Aslani added an answer in Network:
    What factors cause changes in ETX value?

    In RPL protocol (Routing Protocol for Low Power and Lossy Networks) we can use Expected Transmission Count (ETX)  as the default metric for rank computation, which is frequently used in lossy networks and shows the number of retransmission. The ETX of a link will be measured and updated continuously, once the link starts to carry data traffic.

    What factors cause increase or decrease in ETX after data transmission?

    Zahra Aslani

    Thanks all for your valuable information about ETX.

    Actually I implement RPL in Matlab simulator.

  • Jason R Plemel asked a question in Cuprizone:
    Is anyone aware of a paper where cuprizone is injected into the brain or spinal cord?

    Is anyone aware of a paper where cuprizone is injected into the brain or spinal cord? I was just wondering if it was possible to induce local demyelination this way.

  • Mohan Thampi added an answer in Pollution Control:
    What are the economic incentives for pollution abatement?

    Should address the nature of the strategy, how it is intended to/actually does function, the challenges facing successful application and how it could be improved.

    Mohan Thampi

    See the following links. From one I should title your  research paper "To Carrot or To Stick". You may want to use the VW diesel sensor debacle if you are doing a  thesis or study. Sort of like banking sins or having a credit card to absolve the polluter's sins or blackmail - pay us not to pollute: 













  • Rohit M Parikh added an answer in Children:
    Which scientific tool can I use to measure the effect of parent-child communication on children's achievement?

    I want to measure the amount of influence parent-child communication creates on individual child for his/her achievement. So I just wanted to ask any scientific tool which I can use to measure children's achievement based on his parent-child relationship or communication or environment.

    Rohit M Parikh

    Scientific tool cannot act as measurement for parent -child communication on children achievement.Science tool can not work as a tool of mind & brain which every human being have with them till that arrival on this Mother Earth.

    Scientific tool with their research can help the humanity with their research  but this tool can not become a part of human sensitivity his intelligence ,his feeling & what not for which they have receive with them as a part of human being which is nothing but god s' given gift.

    This Is my personal Opinion 

  • Alex Kotelnikov added an answer in Sugar Beet:
    How can I forecast internal temperature in a sugar beet clamp based on weather forecast & current log of temperature sensors in this clamp?

    We have a 22 sugar beet clamps for a long-term storage. Every clamp monitored with the temperature sensors.

    I need to extrapolate respiration process based on a some extrapolation function. This task has a decision, and we can test it on our storage field.

    But I need to correct the forecast with the weather forecast?

    Does somebody have such experience?

    Maybe you know some articles or researches on the sugar beet clamp thermodynamic?  

    Alex Kotelnikov

    Dear Fabio,

    thank you for your answer.

    it's may be useful i think.

    as for a me i think about another way: build a thermodinamic model of sugar beet clamp. then use a correction on a heat transfer. I found some works wit the teoretical calculation of the living houses heat modelling