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  • Miranda Yeoh added an answer in Humanism:
    Who is the most influencial person in the history of your country, till now, and why?

    Every country has produced some exceptional leaders, philosophers, writers, sport persons, and/or artists,....etc. etc.....

    Who do you think is the most influential one based on her/his overall contributions to the society and people of your country/region/world/humanity?

    Thank you very much for your thoughtful response and valuable time.

    Miranda Yeoh · Selangor Matriculation College, Malaysia (Kolej Matrikulasi Selangor)

    In my country, the most respected person is still Tengku Abdul Rahman, our first Prime minister.  He was Chief Minister of the Federation of Malaya from 1955, and the country's first Prime Minister from independence in 1957. He continued as the Prime Minister after Sabah, Sarawak, and Singapore joined the federation in 1963 to form Malaysia. He is widely known as Bapa Malaysia (Father of Malaysia).

    The pic shows the celebration of the first national day, 31 August 1957.

  • Hossam Hosny added an answer in Regional Anesthesia:
    Which anesthetic technique do you use for fracture humerus surgery?

    Which anesthetic technique do you use for fracture humerus surgery? If i choose to do regional anesthesia, i've noted that sometimes the brachial plexus block isn't enough to cover the surgical pain. What's you experience? Thanks.

    Hossam Hosny · Sohag University

    In our institute, we use general anesthesia. We use regional anesthesia in complicated cases not fit for general anesthesia. In regional anesthesia, the patient is awake and hears everything in the operative room and it represents shock for some peoples.

  • Vishal Dubey asked a question in Employment:
    How beyond the monocentricism in the global south?

    Whether the evolving polycentricism in the Global south is only a morphological changes of the urban spatial structure or its also incorporate the functional & economic linkages between the various centers & sub centers across the hinterlands. 

    Number of  studies accounted that the cities in the global south are not yet  Pure Polycentric. primarily the cities spreads to the outer fringes by the de-concentration of population from the core to the peripheral locations  featuring the contiguous built up zones.

    Nonetheless, this  does not qualify the polycentric urban structure in the city region. Therefore the transformation of  monoconcentricity to polycentricity urban structure should also characterize by the emergence of sub urban employment sharing substantially to the overall employment in the defined city region.

  • Jürgen Denecke added an answer in Fungal Culture:
    Is there any protocol for secretory protein enrichment from fungal culture (Ascochyta rabiei), to be used in western blot experiments?

    These secretory protein would be used for relative expression studies.

    Jürgen Denecke · University of Leeds

    You can use spin dialysis (for instance centricon filters) to concentrate the proteins in the medium without having to precipitate (and loose activity). Essentially, you pipet the diluted culture medium into the filter, centrifuge it, and water + solutes below a certain molecular weight (i.e. 10 kDa) pass through the filter, larger proteins stay in the medium on top of the filter in a more concentrated form. Use a refrigerated centrifuge to avoid proteolysis, fungi secrete loads of hydrolases. You can easily concentrate 2 ml of medium to just 200 microlitres in half an hour, that is a 10-fold concentration. The filters come in different sizes and different molecular weight cut-offs (3 kDa, 10 kDa, 30 kDa...)

  • Sönke Dangendorf added an answer in Sea Level Rise:
    Will a rise in sea level at Antarctica affect Mediterranean Sea?

    The ice around the edge of Antarctica is melting faster than previously thought, potentially unlocking metres of sea-level rise in the long-term, researchers have warned.

    A team of US scientists looked at 18 years’ worth of satellite data and found the floating ice shelves that skirt the continent are losing 310km^3 of ice every year. One shelf lost 18% of its thickness during the period.

    The loss of ice shelves does not contribute much directly to sea level rise. But they act like a cork in a bottle at the point where glaciers meet the sea – jamming the flow of ice from the massive ice sheets of east and west Antarctica

    (Source: http://www.theguardian.com/environment/2015/mar/26/collapse-antarcticas-glaciers-ice-melt-sooner-than-thought-scientists-warn)

    Sönke Dangendorf · Universität Siegen

    Dear George,

    your question is a bit unclear to me. How can a sea level rise around Antarctica affect sea level in the MedSea? I suggest you mean the effect of mass input from Antarctica on the MedSea.

    If yes, the following figure provides you the answer. A melting of ice will lead to gravitational changes and a respective redistribution of water into the far field of the ice sheet:


    The figure shows you the dimensionless scaling factors of such "events". You can simply multiply the added mass with the respective scaling factors to get the sea level signal at each grid point. Since the MedSea is in the "far field" it has a positve scaling factor around 1 meaning that 1 mm sea level change coming from Antarctica will lead to roughly 1 mm sea level change in the MedSea.

    Hope this answers your question

  • Mohammad Mohkami added an answer in Fullprof:
    How can i use Fullprof software for XRD analysis?

    i can not download tutorials of the software and i want to know how to use this program.

    Mohammad Mohkami · Islamic Azad University Science and Research Branch

    You can read the following web page, and use this PDF file.


  • How can I extract DNA from very small amounts of mycorrhizae?

    I have some very small mycorrhizal samples (only micrograms per sample) that need to undergo DNA extraction, but I've never worked with such a low amount of sample before. Normally I use a PowerSoil kit, but would put in at least a quarter of a gram. Can anyone recommend a method that would work on such small quantities? I'm nervous of taking a risk and losing the sample.

    Thank you :-)

    Francisco Adriano de Souza · Brazilian Agricultural Research Corporation (EMBRAPA)

    We are also using QIAGEN Plant DNEasy kit for extracting DNA from AM fungi colonized roots using 10 to 50 mg of fresh roots. However, we carefully grind them using liquid nitrogen, and recover the material with the lysis solution.

  • Fajar Abdurrahman asked a question in Microcontrollers:
    How to check the parameter of face in MATLAB?

    i want to build a security system based on face recognized. The idea is to sent the parameter of our own face to microcontroller. is it possible? please help me...

  • Debajyoti Biswas added an answer in Inkjet Printing:
    How do you re-disperse dry PEDOT:PSS pellets in water? Do you use any additional solvent?

    The main reason is to use it as an ink for inkjet-printing.

    Debajyoti Biswas · Indian Institute of Technology Madras

    Have you tried DMSO or any other non-ionic surfactants?Also,the use of water has very few mentions in literature..Forgive me for being curious,but is it a potential solution method for the clogging problem?

  • Gyorgy Banhegyi added an answer in Lacquer:
    How can I determine precisely if I have a cohesive or adhesive failure in a metal-lacquer-polymer composite after a peeling test?

    In some samples, a visual inspection shows "shadows" that could be traces of the lacquer adhered on the thermoplastic material after the peeling test. In other samples it is difficult with just a visual inspection.

    Gyorgy Banhegyi · Medicontur Ltd.

    Reflection IR and XPS spcetroscopy can of considerable help.

  • Adam Kubas added an answer in Diatoms:
    What do you think about recent JCTC paper of Truhlar et al. about benchmarking DFT against CC for TM complexes?

    Hi All,

    I have just read very recent paper "Do Practical Standard Coupled Cluster Calculations Agree Better than Kohn Sham Calculations with Currently Available Functionals When Compared to the Best Available Experimental Data for Dissociation Energies of Bonds to 3d Transition Metals?" by Xuefei Xu, Wenjing Zhang, Mingsheng Tang and Donald Truhlar published in JCTC ("just accepted"). Here is the link:


    They looked how few DFT functionals perform for the dissociation energies of a set of diatomic, transition metal-containing molecules and compared this to the performance of a hierarchy of CC approximations (CCSD, CCSD(T), CCSDT, CCSDT(Q)). They concluded that CC, although much more elaborate and time consuming, are not better than modern DFT functionals. They also questioned benchmarks of DFT methods against CC for TM systems. 

    With the results they presented the conclusions are right. Of course, as they properly noted, if the experimental data change the trends can also be changed. As I'm personally interested in TM compounds and do a lot of calculations on these systems (DFT, single- and multireference wavefunction-based methods), I'm quite surprise that they make such strong statements. 

    First of all, I would never use CC methods for the molecules in question. Multireference treatment would be preferred. Linear molecules tend to have near-degenerate states. Most of the complexes we deal in real life have stronger ligands and way lower symmetry and consequently highly single-reference character. The latter, as properly pointed by authors, is not well defined. In fact, T1, M and B1 diagnostics used in the paper do not seem to correlate between each other. 

    In larger systems weak interactions tend to have really large impact and consistent solution for this problem is still not definitely done in DFT. The DFT errors here can reach more than deviations presented in the paper.

    Although the paper is very solid, I'm a bit sceptical about the generality of conclusions made. I would be curious to hear your feelings about this paper and about benchmarks for transition metals in general. 

    All the best,


    Adam Kubas · Max Planck Institute for Chemical Energy Conversion

    Indeed, the basis set incompleteness error (BSIE) in DFT and CC is rather different. Probably the authors just wanted to use a typical protocol people would follow when benchmarking DFT, i.e. DFT with reasonable basis set (typically of TZ quality) and CCSD(+some treatment of T, rarely Q) with moderate basis set. However, if you can afford calculations like in the paper, then next step would be something that accounts for BSIE. One typically takes two point extrapolation, corrects with MP2/CBS or uses F12 approach. I just think it is unfair to stop at the level they done.

    DFT has larger error spread and this would be quicker visible from RMS error, I agree. Probably one should always provide as much statistics as possible to avoid overinterpretation :)

    I also do think that benchmarking with CC methods for TM compounds still has bright future because:

    1) many complexes/reactions are still single-reference problems,

    2) if 1) is not true then use MR-CC and if impossible then MRCI, NEVPT2, CASPT2 etc. At this point do not expect that DFT will do the job either. You can just be lucky.

    3) whenever possible go to CBS. There are various ways to do so.

    4) points 1-3 become more and more feasible with locally correlated methods, efficient parallel computing etc. we will definitely see explosion of wave function based results in the nearest future!

  • In your opinion, what are the top 3 innovation fields in power distribution systems?

    This is a general question and does not have a unique answer. In other words, what are the present biggest challenges in power distribution systems (Management, Operation, Protection, ... ) that need new solutions. 

    Rajeev Kumar Chauhan · University of Texas at Austin

    1. DC Microgrid

    2. Energy management

    3. Interconnection of DG

  • Rosanna Viscardi added an answer in Films:
    How do I analyze the AFM phase?

    AFM images are of tio2 films 

  • Raid Amin added an answer in Cluster Analysis:
    How can I do a cluster analysis on a very large data set?

    I have access to data on some variable for the 48 contiguous states. I have data at four level of details:

    1. counties (3109)

    2. census tracts (about 70,000)

    3. block groups (about 200,000)

    4. blocks (about 10,000,000).

    I want to make use of block level data somehow.

    The software that I want to use does not manage a cluster analysis at the block level.

    What would you do?

    Raid Amin · University of West Florida

    Hello Richard,

    Thank you for your detailed feedback to my question. I need to know from you the following:

    1. Which computer are you using?

    2. Which cluster analysis software are you using? 

    3. What does DDC stand for?

    I am analyzing air quality data for the 48 contiguous States in the USA. When we try to use SaTScan for a cluster analysis, it does not seem to be manageable with our PC for 10 million values (lat, long, air quality score). We use circular shaped windows in SaTScan, with max window size 5% and with the Normal model. I wonder whether we are doing something  incorrectly or whether SaTScan requires a lot of memory due to the built-in Monte Carlo algorithm to estimate the p-values for the Likelihood Ratio values. Our "Step 3" does not run for so many values. I asked Martin Kulldorff (Harvard U) about it as he created SaTScan, and he told me that I would need a very fast computer to be able to run SaTScan with so many values, and this is not guaranteed to work either.


  • How can we increase the genetic diversity of a particular Sps of plant which is in critically endangered?

    which conservation strategy is more suitable for such a condition.Is it possible to change the IUCN status from endangered to lower risk?

    Pablo G. Goicoechea · Neiker-Tecnalia Basque Institute for Agricultural Research and Development

    Well, it depends on particular situations.

    If critically endangered refers to a particular population, but there is additional germplasm available in other areas, you could just proceed with some introductions. Whether private alleles will be kept or not is serendipity.

    If the species is critically endangered in the whole distribution area, you could translocate plants/progenies among locations, and hope that future crosses among the most distant phenotypes produce some type of "hybrid vigor"..

    indeed, you could mutagenize the gametes during meiosis, but this would produce a very large genetic load.

  • How would you define the difference between adhesion, tack, friction in the case of soft interfaces?

    Ahesion is more or less straightforward if we want to glue together tow metarials. Peeling test works if one of the substrates is flexible. The physical picture is more or less clear. But how can one handle soft/soft surfaces e.g. between rubber and thermoplastic? There is no inteded adhesive layer, but there is some adhesion. If we want to move the two surcfaces against each other, we will experience resistance which depends on the medium, on the chemical composition of  both components, on interfacial stress, complicated further by rate effects (stress relaxation etc.). The situation is even more complicated in biological systems. Here simple concepts as work of adesion (hysteresis), peeling etc. do not work. What are the best characterization techniques?

    Gyorgy Banhegyi · Medicontur Ltd.

    Thank you for both comments

  • Is there any mailing-list, community or forum for researchers studying Visual Sociology?

    I would like to contact with other researchers on Visual Sociology, do you know if is there any mailing-list, community or forum?

    I appreciate your advice

  • Vilas Patil added an answer in Oximes:
    How can I remove nitrile impurities from the oxime?

    I have tried to purify oxime by column chromatography as well as by re-crystallization. I also tried with solvent treatment process (DCm-pentane). On TLC I am getting a single spot but when I carried out GC-MS of those samples it shows presence of nitrile in the purified product. I dont understand why this is happening?

    Vilas Patil · Institute of Chemical Technology, Mumbai

    Dear sir  you are right. I observed this almost for all my samples. 

  • Rajeev Kumar Chauhan added an answer in Battery:
    What is the SOC limit for Iron-Phosphate?

    I m working on battery i want to know the SOC max and min limit for Iron Phosphate battery?

    Rajeev Kumar Chauhan · University of Texas at Austin

    If you are talking about the SOC practical (Hardware), Most of the battery bank has the SOC range 20-100%. I mean as the SOC reach at 15-20 % then battery behave like fully discharge. 

  • Are all economic relationships non-linear?

    Keynes given the theory of price and wage sticky-ness and ascribed it to asymmetry of human expectations and behaviors.

    Many other behavioral economists such as Shiller, Kahnemann and Taversky they are also of the non-linear or asymmetric behavior as people respond more to negative than to similar positive. In this connection one more famous line is companies are slow to hire and fast to fire.

    As most of movements in variables of economics whether macro-economics or international economics is due to collective response of human beings. Thus, nonlinear testing or threshold or some regime switching models must be used more frequently than linear models in research papers. But reverse happens. What are the reasons for more papers on linear testing in empirical studies?

    Roman Matkovskyy · ESC Rennes School of Business

    The truth is never linear. Linearity is just an approximation.

  • Saravana R K Murthy added an answer in Cell Passage:
    Transfected NIH-3T3 cells growing slow. Any tips to speed growth?


    After doing a limited dilution (1 cell per well in a 96-well plate) of tranfected NIH-3T3, I noticed this one colony of cells (passage 12) are growing slower than normal. Do you have any tips to grow faster?

    I've heard that splitting the cells more often or growing in 20% FBS might help. Any advice will be appreciated

    Saravana R K Murthy · Scanogen Inc, Johns Hopkins Fast-Forward, Baltimore, United States

    I would suggest, you should do a mycoplasma contamination analysis for your cells first. If your cells are free of mycoplasma, raise your FBS to 15% for two passes and 20% for two more, then once your cells picks up growth speed then bring back the FBS to 15% and finally 10%. 

  • A. B. Samui added an answer in Adhesion:
    What is an alternative to peel test for adhesion?

    Hi all,

    we are trying to quantitatively compare the adhesion characteristics of surfaces (polymer and metal). For that, we use Instron 5544A and perform a peel-test. That means, we scratch a small section of the polymer and let the machine peel it Toff.

    Though, for some of the samples that we prepared, the adhesion between the layers is so strong that we can't even scratch the polymer and start the peel test. Strong adhesion is desired for our case; but we need to show some data to prove it. Do you have any suggestions to quantify/prove the adhesion superiority for such cases (eg. UV treatment before test, using a different test equipment etc.)?

    Thank you,


    A. B. Samui · Defence Institute of Advanced Technology

    Adhesion tests are plenty, such as, dolly pull off (Dolly made of metal and between two vertically alighned dolly apply adhesive thin layer. let it cure for about 16-20 h). As suggested by Mr. Ebrahim increase the load capacity of UTM machine and test.

  • What is the best chlorophyll source for natural pigmen?

    I am looking for chlorophyll sources with the highest yield or highest color intensity for natural pigment.

    Thank you

    Puganeswary Sukumaran · Putra University, Malaysia

    Microalgae: Spirulina....

  • Jürgen Denecke added an answer in Rooting:
    Rooting of mascarocoffea

    What plant regulator is best for rooting mascarocoffea?

    mascarocoffea belongs to the coffee family. Absence of caffeine.

    Jürgen Denecke · University of Leeds

    1 mg/litre NAA in MS2 medium should be fine, make sure you have nice sharp stem cuttings with a healthy young apical shoot (small leaves), it is extremely important to have neat cuts using a sharp scalpel and using a sliding motion, rather than chopping (and crushing part of the tissue). It can easily take 4 weeks before you see roots, so don't loose heart. The 100% humidity in the sterile glass jar keeps the plant alive, even if you don't see any progress. Do many of them so you have more chance of success.

  • Mona Bayoumi added an answer in Power Generation:
    How can I change the nominal power of the generator DFIG and SCIG during simulation?

    My project is depend on changing the nominal power of the generators, transformer and loads during simulation But when I do it with command set_param error appear, the error is {Cannot change parameter of generator while simulation is running.) I want to change the nominal power of these block especially generators. How can I overcome of this error? 

    Mona Bayoumi · Benha University

    Thanks a lot Dr Ali

    sir if i design the model (generator) i can change the nominal power during simulation or not???

  • Calculation of dielectric constant from impedance spectroscopy data?

    I have measured electrical conductivity of a material by using impedance spectroscopy (IS). The obtained data from semi-circle of Nyquist Plot is resistance (Z). I am wondering that can I calculate dielectric constant from this data?

    Wirat Lerdprom · Imperial College London

    Dear Dr Brus

    Does it mean the capacitance can be obtained (in Zview--for example) by fitting semi circle? I did put R and C in a series circuit when I fitted a semi circle and the intercept is Z.

    I really appreciated your help and looking forward to hear from you.

    Best regards, Wirat

  • Yoshiyuki Numasawa added an answer in Neuroimaging:
    Why does my DTI_FA.nii.gz file show blank mask in FSL?

    I've completed a DTI analysis with FSL before (tutorial data) with no issues. However, when I use my labs data, FSL won't produce a proper output. Literally a blank white mask is shown when I enter DTI_FA into FSL View. When I enter the original unprocessed nii.gz image I see a normal brain scan.

    I used this tutorial: http://www.cabiatl.com/CABI/resources/dti-analysis/

    I downloaded the DCM files from my server (ep2d_DWI) scan and converted them to FSL_4D files with dcm2niigui giving me bvec and bval outputs as well.

    I'm wondering if my issues are with the bvals, as it only has 3: '0,500,1000.' Where usually the tutorial files have 0, 1000 (repeated 20 or so times). In FSL View I see the following information when I only input the 4D file converted from DCM. 

    Voxels: 128x128x24

    Dimensions: 1.71875x1.71875x6mm

    Volumes: 3

    Data type: signed short (16bpp)  

    Any Ideas??

    Yoshiyuki Numasawa · Tokyo Medical and Dental University

    I think the original DCM data you downloaded was not the dataset of DTI.  The way of acquisition of DTI data by MRI is different from that of routine DWI image. 
    The problem is not the conversion of file type, but the DCM file you downloaded. 

  • Choen Krainara added an answer in Critical Thinking:
    Critical thinking vs. truth in education?

    Many educators claim critical thinking as one of the major skills for 21st century students. Students may challenge any 'fact' to construct their own body of knowledge. 

    On the other hand, educators have to build on some truths (e.g., in maths we use axioms) in their teaching. This can be overwhelming students. How do you, as a teacher, find the right balance?

    Choen Krainara · Asian Institute of Technology

    Critical thinking is skill built on learning and experiences.It is worthwhile if we can teach or stimulate during childhood so that they will become confident in expressing critical ideas or analyses. Such level of critical thinking of students may vary from country to country possibly depending on enabling culture and environment.

  • Joe Dunbar added an answer in Hair:
    Hair cortisol labs in the US?


    I'm trying to compile a list of hair cortisol labs in the Us, as we just opened up a new lab at my university. Having contact with these other universities and professors would make the setup process go a lot smoother. 



    Joe Dunbar · Ipro Interactive

    Hi Alex

    I am based in the UK in a company that does salivary diagnostics.  However, I know that Salimetrics in Europe run hair samples on Salimetrics ELISA kits very successfully and I understand that this process is also used in Australia.  We find Salimetrics ELISA kits to be as good  and this was confirmed in Psychoneuroendocrinology 2013, 38, 50-57.

    I hope that helps a little