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
  • Sasaki Hirokazu asked a question in TSP:
    Is it possible to measure surface temperature using TSP with SLR camera?

    I am trying to quantify Temperature distribution on the surface using TSP with SLR camera.

    I'm in trouble with Image processing after getting each Temperature Images. I have tried to develop from Raw to Tiff,but the intensity of TSP didn't decrease enough and correctly as temperature rising higher.
    I think that this reason is my image processing false.But I cannot comprehend what is wrong.

    If you wouldn't mind,would you be able to tell me how to process Images after taking images with SLR camera?

  • Eljelani SALIM Salim added an answer in Eimeria:
    Does anyone know of a simple, fast method to detect oocyst in faecal sample?

    Does anyone know of a simple, fast method to detect Eimeria oocyst in faecal sample?

    Eljelani SALIM Salim · University of Salford

    Can any one advise if this protocol usable with Cryptosporidium oocysts or not, and  how mush suger:water should be enough for getting 1.25 specific gravity?

    Regards,

  • 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.

    Eugene F Kislyakov · Belarusian State University

    Marc,

    he is in Athens.

  • Does anyone know a suitable HPLC method to analyse organic acids such as formate and lactate as well as others SCFA?

    We are trying to analyse organic acid production from bacteria supernatants by HPLC. We tried some methods that we found in the literature but we are having problems with some organic acids like with lactate and formate, they elute together. 

  • Willy Hanugrah Gusti added an answer in PMBOK:
    Please help for the analysis of my research on Risk Identification of Piping Work in EPC Factory Plant Project?

    I am currently doing my final project entitled "Risk Identification of Piping Work on EPC Factory Plant Project to Enhance Time Performance Based on PMBOK Guide 5th Edition". The type of my research is case study in one EPC company in Indonesia. Therefore, my data is primary from the people working in the EPC company.

    I am still confused about the analysis of the data. Do I need to create a correlation analysis and regression modelling for this type of research? I did Normality Test for my data and the result is that the data distribution is not normal. Based on what I read on the journal, regression modeling could not be assessed with data which is undistributed normally.

    Thanks for your help.

    Willy Hanugrah Gusti · University of Indonesia

    @Matilde :  The type of my data is undistributed normally, therefore I use non parametric measures. Thanks a lot!

    @Niels : the purpose of risk identification is to identify any risk related to piping construction work in EPC plant projects. My data is based on opinions from people working in the EPC company I've chosen as the case study. Thank you.

    @Patrick : Yes, it is technical. I just need to know, does "Risk Identification" need "Regression Analysis" as one of the tools to analyze? As far as I read on PMBOK (Project Management Body of Knowledge), in order to identify risks, all I need to do is to interview experts, brainstorm with them, and create a risk register. Thanks!

  • Significant change in Control group- How to address this issue?

    A study on effect of a particular yogic maneuver was carried out in our department. It involved two groups, control and intervention group( n = 50 in each). It so happened that, at the end of study period cardiovascular parameters like BP, HR  showed significant fall in the intervention group, at the same time the other group which was not having any intervention ended up showing a significant increase in BP and HR at the end of the study period. Now how to do i account for this? Has any one come across such a problem before? 

    Ronán Michael Conroy · Royal College of Surgeons in Ireland

    A significant change in the control group is not a problem in principle. In many cases the control group will change for any one of a number of reasons:

    - test sophistication: the second time that people are assessed, they are more familiar with the assessment (less anxious, for example) and with any tasks involved (so they may have learned skills that help with taking the test)

    - regression to the mean: trials often enrol participants who meet threshold criteria. For example, they may have a blood pressure greater than a given figure. Or the participants themselves are at the point where they have just sought help for a problem because it's worse than usual. In each case, measuring them at a second time point will give you a different mean value simply because of random fluctuation in the parameter used to define trial entry

    - method of measurement may change. I would suspect this one in your case. We had a study where the pre-trial ECGs were read by one doctor, and the post-trial ECGs were read by another (the first doctor died during the trial).The discrepancies were such that we had to have all the pre-trial ECGs re-read by the post-trial doctor.

    But the whole point of a control group is that these changes are accounted for in the design. The analysis model is comparing intervention and control, with adjustment for baseline values.

    However, a change in an unexpected direction in your control group will require some explanation when you go to publish! Have you any ideas??

  • How to calculate the sample size when the incidence of any disease of inborn errors of metabolism is 1 in 1000?

    Should I carry out a case control study or cross sectional study in case where incidence is very rare such as 1 in 1000 or so?

    Gyanendra Kumar Sonkar · King George's Medical University

    Thanks Dr. James. This means I should do a case control study rather than going with cross sectional study. Can you plz let me know the sample size if the incidence (not prevalence) given for inborn errors of metabolism is 1 in 1000. (acc to research publications)

  • Krishnan Umachandran added an answer in Marketing:
    Which metrics to use to measure marketing effectiveness and marketing efficiency?

    Which metrics should we use to measure marketing effectiveness and marketing efficiency?

    Do you agree that marketing performance = marketing effectiveness + marketing efficiency + adaptability ?

    Please list those metrics that you usually use in your MPMS. (marketing performance management system).

    @ Kenan

    Please refer to the publication in RG for more Performance measures used in my organization, titled :Developing Marketing Performance Measures in Recession Economy

    https://www.researchgate.net/publication/274639858_Developing_Marketing_Performance_Measures_in_Recession_Economy

  • S. Wenkart added an answer in Plant Tissue Culture:
    Can we go for rooting first and then shooting in plant tissue culture?

    While working with PTC sometimes we encounter rooting first in the explant and so can we develop protocol having the root initiation first.

    S. Wenkart · Ben-Gurion University of the Negev

    If you look at these roots from callus: they are white and thin and do not resemble real roots.

    Even though lateron you get rooted shoots, after changing medium, one cannot be sure if these are funcitonal roots and well connected to the shoot whithout breaking off. Its a tricky business.

  • Is anyone experienced with a nucleolar staining using antibodies against transcription factors in human tissue?

    Some of you can tell me if some transcription factors, apart Hif1a, are expressed in the nucleoli? Also, is some of you experienced with a nucleolar staining using antibodies against transcription factors in human tissue? Thank you for your answers.

    Barbara Serafini · Istituto Superiore di Sanità

    Thank you Vincent. The websites you suggest are very interesting and perhaps I have found what I'm searching for.

    Barbara

  • Anja Schwiebs added an answer in MTS assay:
    Can anyone suggest a good protocol to culture bone marrow derived DCs after isolation?

    1)I need to perform a MTS assay and a western on those cells. Which day would be ideal for me to start my drug treatment. Also my drug does not kill the DCs  rather it promotes their maturation. So I initially need the DCs in an immature state for my assay. Any help regarding this would be deeply appreciated.

    2) In a 6 well plate how many DCs per well do I need to plate to attain full confluence so as to get an optimum protein concentration (for western) 

    Anja Schwiebs · Goethe-University Frankfurt am Main

    For WB we use 5 * 10(6) cells in a 6cm dish. In a 6-well plate we use 2 * 10(6) cells maximum that we seed and stimulate 7 days after bone marrow isolation/maturation.

  • Eric Michael Prager added an answer in Clampfit:
    Pclamp or clampfit softwares for mac system?

    If there are Pclamp or clampfit softwares available for mac system? For patch clamp recordings or data analysis? Where could be download?

    Eric Michael Prager · John Wiley And Sons

    That is why the founder of axograph left molecular devices. He wanted to integrate pclamp to make them make compatible but the company didn't so he left and started his company

  • Is there a role of CA 15-3 as a biomarker for breast cancer in the surveillance of a properly selected group of ”high risk” women?

    As a radiologist, interested in cancer imaging, i came across a publication
    (Atoum, 2012), that could show correlation between elevated CA 15-3 and stage II-III breast cancer.

    Of course CA 15-3 cannot detect early stage breast cancer and is therefore not recommended in screening (Duffy, 2006). 

    But sometimes it can be challenging to find a 2-3 cm diffusely infiltrating breast cancer in asymptomatic - especially premenopausal - women with dense tissue (Buist, 2004. Kolb, 2002).

    A serum marker might be helpful to select patients for further evaluation, e.g. Breast-MRI, tomosynthesis or ultrasound, in order to find “medium size” breast cancers, that otherwise would go undetected by mammography for quite a while with worsening prognosis.

    Efren Bolivar Abreu · Instituto de Oncología Luis Razetti

    Hi Holger. I don't use

  • Martin Jakob added an answer in ImageJ:
    What is it I get after adding an original image to its edges?

    Hello imaging people,

    My theoretical knowledge in imaging has come to an end here. I was wondering what it is I was getting as a result after applying some functions to an image.

    Maybe some introducing words: I wanted to test the javaclass "RGB to CMYK" for imageJ. In order to test how good the separation was, I searched google for magenta images. I took an image of a magenta colored dress. Then I applied the RGB->CMYK function and got the 4 expected channels.

    to all 4 channels [i] I did the following:

    1) edge detection
    2) image calculator: original_image[i] <ADD> edge_image[i]

    then I simply made a z-projection (sum slices) of the channels.

    now I got these beautiful patterns (See attachment), in my opinion showing the dresses wrinklings, but apparently there are other patterns (maybe moiré?) for example on the heel of the display dummy.

    The other thing is I repeated the same procedure with tons of other images but mostly the results looked much more noisy.

    what is the theoretical foundation on how I ended up having these patterns being revealed so nicely?

    Can anyone explain?

    Thank you

    Martin Jakob · Universität Bern

    Thank you! This was very helpful! :-)

  • Philippe Frit added an answer in Werner Syndrome:
    Does anybody knows telomerase mutations (in) related to Werner Syndrome?

    Telomerase mutations have been reported with several human genetic diseases such as DKC, IPF etc., I would like to know whether any telomerase (either in TERT, TERC or DKC1) mutations have been reported/ linked to Werner Syndrome? 

    Philippe Frit · French National Centre for Scientific Research

    Heterozygous de novo mutations in the Lamin A/C gene (LMNA) have been described to cause Atypical Werner Syndrome, but to my knowledge none in TERT or TERC genes.

    But there are still several genetically uncharacterized AWS patients ...

  • Nabil Bella added an answer in Concrete:
    Can the compressive strength of concrete be improved by making modifications to CFRC?

    addition of coconut fibre to concrete has resulted in an increase in tensile strength, however there was a decline in the compressive strength when compared to 28 day strength of normal concrete.

    what could be the possible modification that could make CFRC more viable as a cheap additive to concrete

    Nabil Bella · Université de Béchar

     You can try to add: water reducer / superplasticizer, to have more homogeneous and more compact concrete, then the compressiv strength will increase, I think.

  • Jens Hartwich added an answer in ArcSWAT:
    Any suggestions on high simulated flow compared with observed one in ArcSWAT?


    Dear SWAT users,
    I hope this message finds all of you in good health,
    I've created a hydrological modelling by using ArcSWAT package for the purpose simulate a stream flow in flat and dry watershed. I have two river gauge stations. The first one entered in the model as ( added table inlet of watershed)and I've made a table to add the daily flow values to the inlet added point. the second river gauge station as (added table outlet) to make a comparison between observed and simulated river flow. The distance between two river gauge stations is about ( 15.5 km). The region is considered one of the water stressed area as the average daily discharge for ten years in the upstream gauge is about (95 m3/sec) and the average daily discharge for ten years in the down stream gauge station is about (20 m3/sec)

    Recently, I've start use SWAT-CUP for the purpose of making calibration and validation to the simulated model (and I'm new user). The first daily calibration (8 years calibration ) I've made in SWAT-cup without changing any parameter I got a high simulated flow (FLOW_out) compared with observed one with (R2=0.35) see the attached picture
    This is the summary statistics I got in my calibration

    ((Goal_type= R2 No_sims= 100 Best_sim_no= 56 Best_goal = 3.510975e-001

    Variable p-factor r-factor R2 NS bR2 MSE SSQR PBIAS KGE RSR VOL_FR --- Mean_sim(Mean_obs) StdDev_sim(StdDev_obs)
    FLOW_OUT_6 0.00 0.15 0.35 -25666.20 0.0062 8.1e+003 8.1e+003 -359.9 -93.98 160.21 0.22 92.59(20.13) 53.96(0.56)


    ---- Results for behavioral parameters ---
    Behavioral threshold= 0.300000
    Number of behavioral simulations = 100

    Variable p-factor r-factor R2 NS bR2 MSE SSQR PBIAS KGE RSR VOL_FR --- Mean_sim(Mean_obs) StdDev_sim(StdDev_obs)
    FLOW_OUT_6 0.00 0.15 0.35 -25666.20 0.0062 8.1e+003 8.1e+003 -359.9 -93.98 160.21 0.22 92.59(20.13) 53.96(0.56)))

    and this this the parameter information I did not change it at the start of calibration
    (( 3 : Number of Parameters (the program only reads the first 4 parameters or any number indicated here)
    100 : number of simulations


    r__CN2.mgt -0.2 0.2
    v__ALPHA_BF.gw 0.0 1.0
    v__GW_DELAY.gw 30.0 450.0
    v__GWQMN.gw 0.0 2.0

    -----------------
    v__GW_REVAP.gw 0.0 0.2
    v__ESCO.hru 0.8 1.0
    v__CH_N2.rte 0.0 0.3
    v__CH_K2.rte 5.0 130.0
    v__ALPHA_BNK.rte 0.0 1.0
    r__SOL_AWC(1).sol -0.2 0.4
    r__SOL_K(1).sol -0.8 0.8
    r__SOL_BD(1).sol -0.5 0.6
    v__SFTMP.bsn -5.0 5.0

    --------------------------------------------------
    example of parameterization:

    r__Precipitation(){1990001-2000265}.pcp 0 0.4
    r__AUTO_EFF{[],11,AUTO_NSTRS=0.6}.mgt 0.2 0.6
    r__BLAI{22}.crop.dat 2 8

    -----------------------------------------

    r__CN2.mgt________1 -0.2 0.2
    r__SOL_AWC(1).sol________1 -0.2 0.1
    r__SOL_K(1).sol________1 -0.8 0.8
    r__SOL_BD(1).sol________1 -0.5 0.6
    a__GWQMN.gw________1 0.0 25.0
    a__GW_REVAP.gw________1 -0.1 0.0
    v__REVAPMN.gw________1 0.0 10.0
    a__ESCO.hru________1 0.0 0.2
    r__HRU_SLP.hru________1 0.0 0.2
    r__OV_N.hru________1 -0.2 0.0
    r__SLSUBBSN.hru________1 0.0 0.2

    r__CN2.mgt________3-6 -0.2 0.2
    r__SOL_AWC(1).sol________3-6 -0.2 0.1
    r__SOL_K(1).sol________3-6 -0.8 0.8
    r__SOL_BD(1).sol________3-6 -0.5 0.6
    a__GWQMN.gw________3-6 0.0 25.0
    a__GW_REVAP.gw________3-6 -0.1 0.0
    v__REVAPMN.gw________3-6 0.0 10.0
    a__ESCO.hru________3-6 0.0 0.2
    r__HRU_SLP.hru________3-6 0.0 0.2
    r__OV_N.hru________3-6 -0.2 0.0
    r__SLSUBBSN.hru________3-6 0.0 0.2


    r__CN2.mgt________7,12,15,16-20 -0.2 0.2
    r__SOL_AWC(1).sol________7,12,15,16-20 -0.2 0.1
    r__SOL_K(1).sol________7,12,15,16-20 -0.8 0.8
    r__SOL_BD(1).sol________7,12,15,16-20 -0.5 0.6
    a__GWQMN.gw________7,12,15,16-20 0.0 25.0
    a__GW_REVAP.gw________7,12,15,16-20 -0.1 0.0
    v__REVAPMN.gw________7,12,15,16-20 0.0 10.0
    a__ESCO.hru________7,12,15,16-20 0.0 0.2
    r__HRU_SLP.hru________7,12,15,16-20 0.0 0.2
    r__OV_N.hru________7,12,15,16-20 -0.2 0.0
    r__SLSUBBSN.hru________7,12,15,16-20 0.0 0.2


    v__ALPHA_BF.gw 0.0 1.0
    v__GW_DELAY.gw 30.0 450.0
    v__CH_N2.rte 0.0 0.3
    v__CH_K2.rte 5.0 130.0
    v__ALPHA_BNK.rte 0.0 1.0
    v__SFTMP.bsn -5.0 5.0))

    Can any one help me to improve the output of this model ? or give me any suggestions?
    Many thanks in advance ,
    Salam :)

    Jens Hartwich · Freie Universität Berlin

    Hi,

    could you show your SUFI2_extract_rch.def?

    Best
    Jens

  • Glancia Fernandes added an answer in Sandstone:
    How to explain the sedimentary structure of the concentric circles in the sandstone?

    It should look like a spiral circles if it will be formed by rotation during the collapse of the delta front (it's low viscosity). But actually it is concentric circles. It's not oncoid or concretion. What's the process to form a structure like this?

    The picture was taken from a piece of drill core of the upper Triassic Yanchang formation in the Ordos basin, central China. The sedimentary settings were deltas-deep lake. And there are a lot of soft sediment deformation structures both in drill cores and outcrops in the Ordos basin.

    Glancia Fernandes · Don Bosco College of Engineering, Goa India

    Dear Renchao Yang

    Liesegang rings are commonly found in sandstones. You could check for it by finding the orientation of the bedding plane of the sanstone with respect to this structure. 

    Good luck

  • What is the current research work on energy efficiency and power constraint in WSN?

    hello 

    i am planning to work on the area of WSN. kindly let me know the work related on power constraint and energy efficiency, and give me some basic idea on it. 

  • Shammi Verma asked a question in Reference Books:
    Can someone tell me about good references/books/literature on Semiconductor Device Reliabilty Testing and their Failure Analysis?

    Also share the name of universities/institutions which provide courses on Semiconductor Device Reliability Testing and Failure Analysis.

  • Loubna Settara asked a question in Pi:
    Who have any idea for resolution of these fractional differential equations?

    $ D_{0}^{\alpha}[u_{0}(t)-u_{0}(0)]=\dfrac{f_{0}(x)}{1-a(t)} $
    $ D_{0}^{\alpha}[u_{1n}(t)-u_{1n}(0)]+4\pi^{2}n^{2}u_{1n}(t)+4\pi n u_{2n}(t)+a(t)u_{1n}(t)=f_{1n}(x)$
    $ D_{0}^{\alpha}[u_{2n}(t)-u_{2n}(0)]-4\pi^{2}n^{2}u_{2n}(t)+a(t)u_{2n}(t)=f_{2n} $

    • thank you
  • Ch Ty added an answer in Dielectric Constant:
    How do I fit a nonlinear curve using the Cole-Cole or Cole-Davidson method of dielectric constant?

    How can i do non linear fitting for real part of dielectric constant? In origin 8.1. 

    Ch Ty · Institute of Technology and Management

    Debasish I m facing problem in equation. What parameter value should be kept it is the initial value of maximum value.and error in compiling. Is there problem related to equation writting

  • Ks Goi asked a question in Equality:
    How to conduct a Mann Whitney Test using Minitab ?

    H0 = the number of production outputs during 3360
    minutes, Y, is equal to 3247 (Y=3247)
    H1 = the number of production outputs during 3360
    minutes, Y, is not equal to 3247 (Y≠3247):

  • What features can be used for body part X-Ray classification?

    I have tried SIFT, SURF and HOG but not getting good results. It would be helpful if someone can suggest me features which are good for X-Ray images.

    I suggest to use original approach based on patent procedure (in my opinion the best solution):

    See:

    http://marcolarosa.blogspot.it/2013/04/il-genio-italiano-nonostante-tuttonon-e.html

    Best regards

    Giuseppe Cotellessa

  • Sudip Mukherjee asked a question in Graphene Oxide:
    Can anyone send me any paper regarding the diffraction pattern for graphene oxide and reduced graphene oxide?

    Please send me any paper where SAED pattern of GO and rGO is there?

  • Glancia Fernandes added an answer in Sediments:
    Has any soft sediment deformation structures been reported from the Dharwar supergroup, India?

    It is known that soft sediment deformation structures occur in water saturated sediments of sandstone-clay units. My interest lies in knowing if any of these features are reported from Dharwad supergroup of rocks, especially in the Greywackes. Kindly suggest. 

    Glancia Fernandes · Don Bosco College of Engineering, Goa India

    In this case how this structure could be interpreted.

  • Matias Duran-Matute added an answer in Comsol:
    Could you give me a solution?

    I am working in fluid dynamics and facing a problem while running the model using time dependent solver. I am using COMSOL 4.3. The error shows are in attachment file. Please try to give a solution regarding the problem.

    Matias Duran-Matute · Technische Universiteit Eindhoven

    I agree with Martin: more information is needed to give a solution. What is the configuration? Geometry? Boundary conditions? Initial conditions? Values of the relevant parameters (viscosity, density or in non-dimensional form Reynolds number, etc. )? I will try to give some general answer which is the most I can do.

    There is one thing in COMSOL that a lot of people forget and that is to assign the value of the pressure at one single point. However, I do not know if this gives the error that you report.

    For numerical simulations in general, singularities can arise due to several reasons. This means that a quantity goes to infinity at one point. One factor is that the problem is not well posed. For example, if the boundary conditions are not consistent: you prescribe a net inflow into the domain with an incompressible fluid. The energy input is much larger than the dissipation; the flow becomes unstable; the energy keeps on increasing; at some point it can grow without bounds. In these cases, you should go back to the drawing board and see if your setup is correct. Increasing viscosity could also help. 

    The algorithms themselves also have some limitations.