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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  • Marković G. Đoko asked a question in Russian:
    Does anyone know how much there is evidence Pythagorean theorem?

    Proof which appeared in Euclid's "Elements" is not Pythagorean proof. Russian mathematician Loomis, was 1940 published a book of mathematics in which there are over 200 proof of Pythagoras teireme. Do you know some proof of this theorem, which so far no published?

  • Heitor Scalco asked a question in Tcpdump:
    How to transform tcpdump data on KDDCup99 format?

    Hello everybody,
    I would like to know how can I transform the tcpdump data to KDDCup99 Intrusion Detection Dataset format.

    I have a trained neural network (with KDDCup99 dataset) and I need validate this neural network with a real network traffic (obtained via tcpdump).

    This dataset contains 41 features, but I dont know how can I preprocess the tcpdump data to be like KDDCup.

    The link for dataset is following:
    http://kdd.ics.uci.edu/databases/kddcup99/kddcup99.html

  • Krishnan Umachandran added an answer in Personality:
    Does the digital personality die when a person dies himself?

    Many of people have a legacy of scientific, literary, photographs and correspondence within the digital world (such as e-mail). When a person dies, who has the right to access  his legacy and personal correspondence?

     Are there laws specify who can accessed or owned the legacy after the death of the person?

    Krishnan Umachandran · NELCAST

    Digital personality is an interesting issue of data diary. As long as it is not used by others after the demise of its owner is justified. Using an account of others aftermath can be through an automated mail to the sender informing them of the sad event but a redirected contact available for further contact, would be advantageous. 

  • Lei Shang asked a question in Stem Cell Differentiation:
    What is the important time point in Mesenchymal stem cell differentiation?

    Hello, everyone. One thing I just want to ask you, because I am a freshman in bone engineering. 

    We all know that Mesenchymal stem cell could differentiate into osteocyte. In this process, Mesenchymal stem cell may first differentiate into osteoprogenitor, and then into pre-osteoblast, then into osteoblast, finally into osteocyte.

    My question may state as following, "what is the important time point in Mesenchymal stem cell differentiation in every differentiation stage??" For instance, when Mesenchymal stem cell differentiate into osteoprogenitor or pre-osteoblast or osteoblast or osteocyte??

    Thanks a lot.

  • Pavan Kumar added an answer in Nanowires:
    Does Williamson-Hall analysis applicable for Core-shell nanowires?

    I have used X-ray diffraction W-H ISM model to estimate the strain in the Core-shell nanowires. Both core and shell are comparable in size (80 nm). 

    Pavan Kumar · North Carolina Agricultural and Technical State University

    Hi Braun, Thank you for the suggestions.

    Yes, the radius is around that. I have done similar study by varying thickness of the shell and compared with just core. I could see a systematic behavior and estimated the strain using shell peak (deconvoluted) by W-H analysis. But one of my friend asked me to check the applicability of this analysis to core shell since they are in comparable size. 

    In my opinion, if both are in same size, may be core also might undergo strain and that can be measured by using core peak. Since i'm using shell peak to estimate the strain in shell there shouldn't be any problem. May be I shouldn't say that the strain measured from shell is total strain in the nanowire. Am I right Dr.Artur ?

  • Hop Tran added an answer in Forest Regeneration:
    Is there a standardized methodology for forest regeneration studies?

    I'm currently working on regeneration of dipterocarp species: it's quantity and quality as affected by varying environmental conditions. Just wanna drop by to ask whether some experts work also in these and can recommend/suggest something relevant on this study.

    Cheers!

    Hop Tran · Massey University

    I suggest you go to Forest Ecology and Management Journal and search for some keywords such as Dipterocarp, seedlings, saplings, regeneration. I know that some scientists from Japan (e.g. Kyoto University and Hokkaido University) have published results on ecology and management of lowland dipterocarp forests in Borneo (Malaysia) based on data collected from long-term permanent plots. Try to contact some of them for more details.

  • Ali Mohammadi added an answer in Carbon Footprint:
    How do you calculate the Carbon footprint for agricultural production? For example, in wheat production.

    How do you calculate the Carbon footprint for agricultural production, For example, in wheat production?

    Ali Mohammadi · University of Tehran

    Hi Mohammad, 

    I found an interesting paper on carbon footprint of durum wheat, might be useful to you.

    http://www.sciencedirect.com/science/article/pii/S0378429011001158

  • Anwar A Hussain added an answer in Microneedle:
    Should Microneedles ideally reach epidermis and top layer of dermis or the blood capillaries?


    Micro needles are suitable tools for injection of compounds. To increase their efficacy in dermal delivery, micro needles should ideally reach epidermis and top layer of dermis OR blood capillaries?


    Anwar A Hussain · University of Kentucky

    IF you can penetrate the epidermis layer you will improve the delivery of the drug by several folds.

  • Kyle Killian asked a question in Writing:
    What are some good unanswered psychology questions to do research on?

    I need help on a topic to write a report on.

  • Michael Cuellar added an answer in Absorptive Capacity:
    What dimensions of Quality of workplace Life (QWL) directly impact Absorptive Capacity (Knowledge Acquisition and Assimilation)?

    what dimensions/ indicators of Quality of Workplace Life (QWL)  directly or indirectly impact two components of Absorptive capacity ( Knowledge acquisition and assimilation ) in context to work shop floor employees? Generally employees were observed as  least interested in gaining new knowledge.

    Absorptive capacity is the ability of organization to acquire, assimilate and use new knowledge in its processes.

    Thanks in advance

    Michael Cuellar · Georgia Southern University

    Dear Muhammad:

    I think your definition of ACAP is just fine.

    As I'm sure you know, ACAP is based in the prior related knowledge possessed by the student. However, it is also a dyadic concept which means that ACAP various based on the similarity of student and the teacher. So you have to examine how the various aspects of the student and teacher match up to determine how well the student is able to learn. So in terms of QoWL, you need to see how the QoWL initiative makes the characteristics of the line people match up with the source of information. 

    The channels used to transmit knowledge are also important. Based on the type of channels ACAP might be greater or lesser. The basic attitudes toward new knowledge are also important.

    You will need to do a qualitative assessment of the characteristics in the light of what knowledge is being transferred in what way. 

    I've discussed all of these in my paper: https://www.researchgate.net/publication/4868437_A_framework_for_ex_ante_project_risk_assessment_based_on_absorptive_capacity

  • Ilya Tsyrlov asked a question in Antiviral Drugs:
    Dear all, what is your point of views regarding the call for broad-spectrum antiviral drugs, based on the pitfalls of this approach with antibiotics?

    The spread of resistance in bacteria is not applicable to viral resistance. The formers can spread antibiotic resistance either vertically or horizontally, while within the latters the evolution of drug resistance is governed by viruses’ intrinsically error-prone replication.

  • Anwar A Hussain added an answer in Permeability:
    Is it possible that the transdermal drug permeation from a polymer alone is better than polymers with penetration enhancers?

    I make a research on transdermal drug release , and i have some foreign release behavior that the drug permeation parameters are better than the permeation with adding different type of penetration enhancers

    Is it true and possible?

    Anwar A Hussain · University of Kentucky

    It may be possible that the rate limiting step is the rate of permeation of the enhancer. the first thing one must look at is the rate of diffusion of the enhancer from the polymer through the skin . the second study is to determine the  solubility of the drug in the enhancer. Is the enhancer  a surface active  agent or  just a solvent such as ethanol. A suggestion to the investor is to try Methyl Salicylate as an enhancer.

  • Utkarsh Maheshwari added an answer in Chitosan:
    Any advice on metal ion adsorption using chitosan as adsorbent?

    Hello everyone,

    I have small doubt regarding my research work. If anyone working on metal ions adsorption using chitosan as adsorbent...please help me out..

    My doubt is,

    Chitosan is soluble in acidic media..so, we can't get metal recovery in acidic state..because adsorbent gets dissolved in solution...but, in so many research articles people reported optimum pH as 2 or 4. My doubt is, if adsorbent gets dissolved in solution, how we observe metal removal. In my case, i got 87% metal removal at pH 4. but, i can't understand the mechanism of this process. so, please clarify my doubt ASAP. Is it i can consider metal removal value obtained at pH 4 (or) if any reason/explanation exists..please tell me the reason.

    without clarifying this issue, i can't move forward in my research.

    So, Please help me out.

    Thanks in advance...

    Regards,

    Srinu Nagireddi,

    PhD research scholar,

    IIT Guwahati,

    India.

    Utkarsh Maheshwari · Birla Institute of Technology and Science Pilani

    Dear Mr. Sinu

    As you and other researchers who had replied are saying that Chitosan is soluble at pH 4 so, I don't think, it can be considered as its adsorption capacity. I think you have to first understand how much of the chitosan is dissolved and then, calculate that how much of the metal is removed using the remaining amount of the Chiitosan. May be, it will give you the correct amount of the adsorption capacity. 

    Also,to understand the mechanism, you can use the isotherm, kinetic and mass transfer models available in the literature. You can even go through one of my paper available at the below link. I have used the three models.

    https://www.researchgate.net/publication/273442447_Removal_of_Cr%28VI%29_from_Wastewater_Using_a_Natural_Nanoporous_Adsorbent_Experimental_Kinetic_and_Optimization_Studies

  • Utkarsh Maheshwari added an answer in Sorption Isotherm:
    Can anyone suggest useful procedures for determining metal sorption mechanisms onto a porous material?

    Regarding this fact that the immobilization mechanism of  metals on another solid can be any of the followings: physical adsorption, complex formation, precipitation, etc, Surface functional groups of the solid has been already determined. Can anyone suggest any other technique?

    Utkarsh Maheshwari · Birla Institute of Technology and Science Pilani

    Dear Dr. Hoda,

    I agree with Dr. Behzad Shiroud Heidari.

    According to me, the mechanism can be understood by adding up the Isotherm model, Kinetic model and mass transfer model results. Also the pH and FTIR studies are important to understand the  mechanism.

    If required, you can check one of my paper where I have done all the three to propose the mechanism.

    https://www.researchgate.net/publication/273442447_Removal_of_Cr%28VI%29_from_Wastewater_Using_a_Natural_Nanoporous_Adsorbent_Experimental_Kinetic_and_Optimization_Studies

  • Manuel Morales added an answer in Theoretical Physics:
    Is the concept of field the proper way to describe physical processes?

    What is a field? Everywhere around a 'source' of the field, if we put a 'test particle', then a 'force' will be applied to it, coming from the source.
    This definition has a critical drawback:

    • if you calculate, using volume integrals, the total energy of the field , then you will find it infinite. Is this acceptable?

    On the contrary, there exists the interaction from a distance view, where a force is applied to the test particle only when it is being present in the neighborhood of the source. So, we have not any kind of infinite energy here.
    Which approach do you believe that is correct and why? 

    Manuel Morales · TemptDestiny.com - Prephysics Research

    Fascinating allegory Charles.

    If physical scale and locality are fundamental, then how can physics be fundamental if it cannot answer the following question:

    How much does a direct or indirect selection weigh, what are their scales, and where was the mutually exclusive selection variable you used to read these words located when you used it?

    Can you answer the question Charles or not?

  • Peng-Nam -- Yeoh asked a question in Ileum:
    How can I remove an unauthorised name, "Mohd Azlan Nafiah" on the authors' list of this papaer?

    Pandanus Amaryllifolius Extract has Anticholinergic and Antihistaminergic Effects in the Guinea Pig Ileum

    The Open Conference Proceedings Journal, 2013, 4: 94

    Peng Nam Yeoh, Kah Yen Koh, Jo Ann Lee, Yu Sui Chen, Mohd Azlan Nafiah
     
       This name "Mohd Azlan Nafiah" has been added without my knowledge. He has no connection with this study and I do not know who he is. How can his name be removed from this paper?

    Peng Nam Yeoh

    Thanks
     
     



     

  • Jiri Koubek added an answer in Ribosomes:
    Does anyone have experience with spindown assays with ribosomes and some of its assoicated proteins?

    I am wondering about how one could quantify the amount of protein that co-sediments with respect with amount of ribosomes that sediments.

    Jiri Koubek · Academia Sinica

    I would suggest western blot with antibodies against your protein of interest. You would need to prepare some standards of your protein, which would tell you how much is present on the ribosome. Ribosome quantification can be done based on the absorbance at 260 nm. It is not completely accurate but it is the easiest way.
    The other option is to do quantitative MS where you spike some isotopically labeled peptides which would be present due to your protein/s.

  • Vyacheslav N Romanov added an answer in PAUP:
    How do I define and name a data partition in PAUP* software?

    I want to perform a partitioned Bremer support (PBS) analysis with TreeRot v3 software, but i dont know how do i define and name a data partition in PAUP* software?

    Vyacheslav N Romanov · National Energy Technology Laboratory

    This question has been answered at the attached link.

  • Jacobo Fernandez-Vargas added an answer in MANOVA:
    Which is the appropriate statistical test for this data?

    I have recorded data from N subjects (for the moment 9, but it will increase). After each experiment I use different analysis and the success rate. The analysis is divided into three parts which can be perform in several ways:

    Start : S1, S2, S3, S4

    Mid: M1, M2, M3, M4, M5

    End: E1, E2, E3, E4

    S4 can be combined only with M4 and M5, while S1..S3 can be combined with M1...M3. E1...E4 can be combined with all the previous combinations. In total there are 44 combinations, for example S1M1E1 or S3M2E4.

    The first analysis that I performed was a one-way ANOVA  to find which was the "best" combination. The next that I want to test is which is the best Start, Mid and End.

    I think that neither n-way ANOVA or one-way MANOVA is the test that I should run, should I group by for example "Start", take the mean value for each subject and perform a one-way ANOVA?  Should I count each of the different results as "Repeated measure"? In both cases I am losing the information about the interaction between "Start", "Mid" and "End". Which is the appropriate statistical test?

    Jacobo Fernandez-Vargas · Chiba University

    It seems I 'm not very good at explaining me, sorry.  As you suggest here is the file with the data.

    Nevertheless I will try to explain again. I want to study which is the best method to process a signal. For processing the signal there are 3 steps: "Start", "Mid" and "End". In total I have 44 combinations of those three conditions for each subject represented by for example S1M3E4 which means Start 1, Mid 3 and End 4.

    "Start" means which is the source of the signal: EEG, EMG, EEG+EMG.

    "Mid" means the classifier that I am going to use: ANN, SVM.

    "End" means the output that I want to classify: Position, Angles.

    For each subject I can calculate all the combinations.

    For each combination I calculate a score (between 0 and 1) and that score is the value that represent that combination for that subject. 

    I already made an analysis grouping them by "Start", "Mid" and "End" and now want to study the interaction between them, if possible.

    Thank you for your pattience.

  • Tiago Amaral TMA added an answer in Parenteral Nutrition:
    When should the parenteral nutrition be started in septic shock patients?

    I'm looking for recent articles concerning the modalities of prescription of parenteral nutrition in septic shock patients, its posology and when to start it

  • Priyavrat Thareja added an answer in Organizational Analysis:
    Any advice on organisation values and their impact on business results?

    I am doing research on the construct of tangible and intangible business impact achieved by rigorous implementation of Organisational Values in letter & spirit in the organisational context. Please suggest published research papers on this subject besides validated construct and questionnaire which can be referred and utilised for validating the above construct.

    Priyavrat Thareja · Rayat Institute of Engineering & Information Technology

    Both Numeric values and cultural Values have a contribution in organisational functioning. Because no organisation can survive without profits, the former are more essential for organisational sustainability. Thus values impact Values.

    This is how I saw them both, and their transformation:

     Values!  Thou have a value

     Values: as quantified by multifarious iterations,

    but indeed, your domain has of lots of accostations,

    because they are hard to find, laborious to match ,

    innocuous to search, and exuberant to define,

    never the less these are quite fathomous to imbibe.

    Yet!  The values in these values,

    whether they justify the extent or levels,

    of measured quantities and their magnitudes,

    continue to remain meer carrier of life-less data,

    dull but prospective; like an unused bedding in a holdall.

    Well! unless these values got vetted by value judgment,

    choosing eclectically, scientifically based, sustainable plots

    which are as factuous as the truth of nearness to God.

    But alas! why could they be hollow rather than being Holy

    unless a right set of values are acclimatized boldly.

    Such values! inspite of their breadth, may remain valueless,

    unless these values do not merely sustain materialism,

    or nurture, notoriously, nature un-friendly methodism,

    and  even if the precious data still devoids shapes,

    It pains, as if those assembled figures are carelessly grazed.

    Yet! these values?

    Of what value are these finally?

    if one lacks the basic and fundamental values !

    Barring, It's like a myth supported preposterously?

    universally, be it an individual, or an organization !

    (c) 2000 Priyavrat Thareja

  • Vyacheslav N Romanov added an answer in Data Visualization:
    In image processing from AFM, how does the scanning area affect the spatial freq. and Gaussian kernel in obtaining a great visualization of the image?

    Scanning area  from micro meter to nano meter scale.

    Vyacheslav N Romanov · National Energy Technology Laboratory

    Assuming that you designed the experiment in a way that the scanning area matches the expected spatial frequency of the imaged features, the S/N ratio reaches its maximum when the Gaussian filter width matches the observed signal width as well.

  • Li Feng asked a question in Population Genetics:
    What is the impact of null allele for population evolutionary history?

    How to rule out the impact of null allele when I do analysis of population evolutionary history, or is there a threshold value for null allele test when below this value, I can continue analysis disregarded some loci contain null allele?

  • Louis Brassard added an answer in Qualia:
    A thought experiment inspired by Chalmers' “Fading Qualia”. What manipulations to the neural circuitry demolishes consciousness?

    Instead of gradually replacing biological neurons with silicon neurons as in Chalmers' Fading Qualia, I attempt to gradually replace dividable functions of biological neurons with silicon emulation.

    The question is, at which manipulation stage does our brain lose consciousness (qualia)?

    1)   Replacement of axonal spike propagation with an external artificial mechanism that uses radio transmission (e.g. WiFi): Causality between presynaptic neuronal firings and postsynaptic PSPs is preserved, but now neurons are physically isolated.

    2)   Further replacement of postsynaptic PSP integration with an external artificial mechanism: Causality between presynaptic neuronal firings and postsynaptic somatic membrane potential is preserved, but now without sophisticated dendritic-somatic computation.

    3)   Further replacement of transformation from postsynaptic somatic membrane potential to postsynaptic firing (Hodgkin-Huxley Eq. mechanisms) with an external artificial mechanism that integrates presynaptic firings and activates postsynaptic neurons by current injection accordingly: Causality between presynaptic neuronal firings and postsynaptic neuronal firings is preserved, but now without an intact internal variable, the membrane potential.

    4)   Mere replay of spatio-temporal neuronal firing patterns by external current injection: Zero causal interactions among neurons.

    Louis Brassard ·

    Jonathan,

    You experience your doing and not all the billion of events allowing it.  You move your leg. If you pay attention to it, you do not really know how you move it but only experience the leg moving and you eyes seeing it. What do we really experience is not even how exactly the leg is moving but just some aspect of that.  Usually we do not pay attention to our leg moving and so we expererience ourself moving on the sidewalk vaguely knowing the cyclical alternation of our leg but we normally put our attention on what is new in the happening, what is threatening, or what is interesting and un-usual.  We do not even move our attention.  OUr attention move to these and we notice what it select.  So there is a nexus of action where the attention move.  This nexus of action is controling this thousand billion cell being.  It does not need to be fixed in the organism and it depend as much on internal events than on external events.  It may be totally free floating in the nervous system.

    I will continue later. 

  • Reza Azin added an answer in Capillaries:
    How will the PVT calculations be affected by Capillary Pressure?

    the PVT calculations, including Bubble point, Dew Point, and Flash Calculations are mostly conducted in the bulk of fluid, ignoring the effect of capillary pressure, Pc, in the porous media. However, the reservoir fluid lies in the pore spaces of porous media where Pc may dominate. My question is to what extent can Pc affect the PVT calculations and procedures? Shall we perform flash calculations instead of single-phase, bubble or dew point, calculations even in the single phase regions as there is a residual liquid or gas saturation? how will be the convergence criteria in this kind of PVT calculation?

    Reza Azin · Persian Gulf University

    Thanks a lot, Alireza for your careful answer.

    We may suppose an ideal system that can produce from all pores. Another issue that remains is that how we can perform a flash calculation in the presence of porous media where Pc is active, and how we can relate the flash calculation results to the saturation (better to say, residual saturation) in porous media.

  • Wen Yao added an answer in Plant Growth:
    Do you have supportive literature to prove plant adoptability to low level of Cd stress?

    I am searching supportive literature to prove the concept, rice plant adaptability to low level of Cd stress (i.e. lower than 3 ppm) relative to plant growth parameters. Can anyone share your experience with me?

    Wen Yao · Huazhong Agricultural University

    You may find this link helpful:

    http://venyao.github.io/RICENCODE/tags.html#cadmium-ref

  • Ali Mohammadi added an answer in SimaPro:
    How can I perform modeling in simapro for LCA analysis of urban water cycle?

    I have the water cycle data. Including chemicals Consumption, energy consumption, equipment used, concrete and steel consumption in the construction of water and wastewater treatment plant. also Characteristics of  raw water and raw wastewater. I'm looking for how to enter the data in   Simapro software.

    Ali Mohammadi · University of Tehran

    In SimaPro, when you defined your project and determined all process which they influence on global warming  impact (CO2 eq.) of your Functional Unit (FU), then you can enter your data into software. First of all, open a directory called “use this directory for your project materials for convenience”. This directory has the different parts for entering data.

    Based on involved processes on your project, you need to fill up these sections. Sections are following as:

    1.       Knowen outputs to technosphere. Products and co-products

    2.       Knowen outputs to technosphere. Avoided products

    3.       Known inputs from nature (resources)

    4.       Known inputs from technosphere (electricity/heat)

    5.       Emissions to air, water, soil

    6.       ….

  • Priyavrat Thareja added an answer in Mentor:
    Are there mentoring programs avaialble for young professional researchers?

    As a recent graduate with a passion for research, I am interested in finding either a mentor or mentoring program that supports individuals in my position to hone their skills and better prepare them to be successful in their field. Does anyone know of any programs or have an interest in mentoring?

    Priyavrat Thareja · Rayat Institute of Engineering & Information Technology

    1. All/ Most institutions mandate undergoing a course on "Research Methodology". To hone one's skills and ensure better preparedness for success is the primary objective.

    2. The research supervisors are responsible for continual mentoring.

    3  I in my institute had organised two such mentoring programmes, one in each semester, coaching 31 and 29 Ph.D scholars respectively.

  • Parul Dixit added an answer in Adipose Tissue:
    Hi. Does anyone have experience with flow-cytometry on SVF (stromal vascular fraction) from adipose tissue?

    How should the voltages be set for forward scatter and side scatter to be able to select different cell populations (lymphocytes and ATMs)? What is the percentage of CD45, CD14 and CD16 and CD16CD14 ++ cells that is usually found in SVF from human subcutaneous tissue? 

    Parul Dixit · University of Otago

    Thank you so much Barbara and Ajithkumar for the reply. The suggestions are really helpful.