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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  • Kenneth M Towe added an answer in Political Action:
    Climate mitigation action?
    What must happen for people to reduce and remove greenhouse gases from our atmosphere?
  • Tatiana Reitblat asked a question in Stem Cell Therapy:
    How to treat patient with inflammatory polyarthritis due to Interferon treatment?

    The 28 years old woman suffered 4 years ago from AML, M3. She entered into remission after immunosupressive treatment and Stem cell therapy. Since that she have been treated by Interferon. 2 months ago she began to suffer from Polyarthritis and Antinuclear Ab positive.

  • María A Gandini asked a question in Rage:
    How can I measure if one specific protein has been glycated?

    I would like to know if my protein of interest is glycated and if it is target RAGE.

    Is there a specific experiment to know if a protein is glycated? Do you know if there is a form to know which lysine is target of this modification? 

  • Is there a solid counter-argument against Dingle's old objection to Relativity Theory?
    Herbert Dingle's argument is as follows (1950):

    According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates,i.e. one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the 'moving' one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, 3 consistently with the theory, which clock works the more slowly? Unless the question is answerable, the theory unavoidably requires that A works more slowly than B and B more slowly than A - which it requires no super- intelligence to see is impossible. Now, clearly, a theory that requires an impossibility cannot be true, and scientific integrity requires, therefore, either that the question just posed shall be answered, or else that the theory shall be acknowledged to be false.
    J. G. von Brzeski · Helios Labs

    When the concept of computed tomography was sent by its authors to some leading journals ( including Nature) in the field , it was turned down " as impossible" . It was also rejected by two Nobel prize winners as "impossible"  So inventors went to industry instead to academia and made it .

    Now those idiots who rejected tomography as" impossible are benefited  from the tomographic diagnostic when they coming to the health care.

    In science , perhaps more than in  other areas of human activity, is a lot of imbeciles  and charlatans living on taxpayer money.  Here Big Bang is one of  the greatest  scam ever.

  • Nihad Aghbalou added an answer in Solar Thermal:
    What is the difference between Plant Load Factor (PLF) & Capacity Utilization factor (CUF)?
    What do they both signify ?
    Nihad Aghbalou · Abdelmalek Essaâdi University

    i guess that capacity factor consist on theoretical performance and the load  factor for operational performance

  • Samaneh Tousi added an answer in LacZ:
    Why is there a preference for the NKX2.5 CreERT2; R26RnlacZ mouse line versus the NKX2.5nLacZ-knockin mouse line?

    Is CreERT2 an unstable structure? Is it true that tamoxifen induction and then Xgal staining shows only the expression site of NKX2.5 at the induction time?

    If we do tamoxifen induction at the late stage of development, would LacZ activity show all regions that express NKX2.5 at the late stage or at the early to late stages?

    Samaneh Tousi · Tarbiat Modares University

    Thank you very much for your informative response.

  • Dear,is there in Your country regulation about the use/ management of underground regarding to the implantation/ maintenance of infrastructures?

    Is it done by public-private partnership or only by government?


    Is the mapping of the underground updated?  Are there  problems with networks interception?

    Thank You very much for helping!

    Vanessa Meloni Massara · University of São Paulo

    Dear Dr. Kamal,
    Thank You very much for Your prompt answer!
    Do You know something about water supply, sewage and electricity underground infrastructures?
    Thank You. Best regards,
    Vanessa

  • What is the correct interpretation of slope and intercept in W-L relationship?

    In weight-length relationship for fish species, according to literature, a is the intercept and b is the slope, so why then some statistic programs show the opposite? In a linear regression using the least square method, PAST says that b is the intercept.

    Also, with a very low value of b (under 1.00), having a sample of almost 100 fish, what kind of conclusions can we draw?

    Thanks!

    Mala Stavrescu Bedivan · University of Agricultural Sciences and Veterinary Medicine of Bucharest

    Dear Julia,
    thank you for your consideration! Yes, my second question was about  the slope. I was interested in correct interpretation of the equation y (total body weight)=0.25x (total body length) + 0.63, considering the fact that exponent b is close to 3.0 for most fish species and my slope has such a low value...

  • How shall i know if the impact factor of a certain journal is true or fake?

    I would like to make sure that the impact factor of any journal is true not fake

    Dr. Mohammad Hamad Al-khresheh · Al-Isra University

    Dear Ahmed, use the Journal Citation Reports (JCR) to locate impact factors. The JCR also lists journals and their impact factors and ranking in the context of their specific field(s).

  • Jason Orlosky added an answer in Biometrics:
    How can one know that how much finger pressure is applied on a fingerprint scanner?

    I am creating a fuzzy set for a biometric signal. The case is when a user places his/ her finger on a fingerprint reader, obviously some pressure will be applied. If s/he applies VERY LESS/ light pressure on the scanner, there are chances that finger minutiae will not be properly extracted; now if a person applies MORE/ TOO FIRM pressure, enough noise can be generated that might not necessarily be removed via SNR technique.   

    I am searching the values in Pascals (or any other unit) for fingerprint when a user apply finger pressure.

    I am searching the following values to fill  

    • Too Firmly = ___ Pascals (Pa)
    • Very Firmly = ___ Pa
    • Properly = ___ Pa
    • Marginally less = ___ Pa
    • Very less = ___ Pa
    Jason Orlosky · Osaka University

    I agree with Faezeh.  You can probably use the total number of extracted pixels as a relative gauge of pressure.  For example, if someone presses too lightly, only a light image with thin lines will appear.  If someone is pressing hard, the lines will become fatter, and the overall image will become darker.

    If you are taking a gray-scale image from the scanner rather than black and white, you could compute a sum of the darkness (overall intensity) for each pixel and use the sum to rate individual fingerprint scans.

  • Can I create a family mold from Solidworks Plastic student edition?

    Am actually working on molding simulation of plastic parts made via injection molding technique but am finding it difficult to create a family mold for my design in order to run the simulation. Could it be because am using student edition of solidworks? 

    Is there a way I can specify the mold material from the solidworks plastic simulation platform?

    Thanks for your responses.

    Agnieszka Katarzyna Dąbrowska · Empa - Swiss Federal Laboratories for Materials Science and Technology

    Have you ever tried Moldex 3D for your simulations? I think using this it could be possible. 

    You can import your project from other software (drawing the form in Solidworks should be not so difficult, I guess, even with student edition. And in Moldex you can set  hot/cold runners etc.

  • What are the indications for laparoscopic highly selective vagotomy with nissen fundoplication?
    There are several articles in the literature on this subject (including publications by many members of ResearchGate): some studies say it is beneficial while others differ. So definite conclusions have not been reached. But I found these studies (including RCTs) don't mention specific indications regarding which patients undergo HSV along with fundoplication.
    Mircea Litescu · Carol Davila University of Medicine and Pharmacy

    The purpose of this procedure was to diminish gastric acid output and to preserve the correct gastric drainage. This goals were achieved by posterior truncal vagotomy and highly selective anterior vagotomy with preservation of the vagal branches that are for the antro-piloric region. The association of fundo-plication was justified because of an extensive dissection of the hiatal region in order to discover the trunk of the  posterior vagus nerve. The anterior one was treated at the level of the superior branches before entering the gastric wall, above the gastric angle. In our department we did performed less than 10 procedures before the year 2000. it was a time-consuming procedure, with not so good results and today we have a better understanding of the mechanisms of ulcero-genesis and far better medication to heal the ulcer. As Prof. Pierre Verhaeghe has already said , today this procedure is history.

  • Cezary Specht added an answer in Atomic Clock:
    What is the timing accuracy among GPS receivers?

    Known primarily as a navigation system, the global positioning system is also used to disseminate precise time, time intervals, and frequency. The GPS
    carrier signals originate from on-board atomic clocks monitored by ground control stations. GPS satellites transmit time signals with each subframe of data modulated onto the carrier. While navigation and survey receivers use GPS time
    to aid in computation of position solutions, time and frequency receivers use GPS satellite transmissions to control timing signals and oscillators.

    Cezary Specht · Gdynia Maritime University

    In GPS we have two types of receivers:

    1. for positioning 

    2. for time transfer signals

    The first one does not guarantee such level of time accuracy. They are only designed for positioning.

    The second one don't present position, but guarantee high level of time signals.

    cezary 

  • Haresh Raval added an answer in Ultraviolet:
    What is the consequence of having singular gluon propagator in some gauge? Is it fine?

    What can we say about the usefulness of this gauge in ultraviolet and infrared region?

    Haresh Raval · Indian Institute of Technology Bombay

    @ Alexei A. Pivovarov: 

    I have not seen any gauge in which any vertex depends upon arbitrary parameter e.g., gauge fixing paramter. But what if  some of the vertex say four gluon vertex depends on it?  Pls comment on the perturbative applicability of the gauge. Can we 'tune' that parameter such that the expression for the vertex goes to zero identically?

    For example: In covariant gauges four gluon vertex has a standard form as in common literature. Now suppose there is a gauge in which this four gluon vertex modifies to (standard form + arbitrary parameter).            

    Can we 'tune' that parameter such that  (standard form + arbitrary parameter) = 0 ?

  • Tomasz Sablinski asked a question in Life Sciences:
    Do you think it is a good idea to crowdsource the design of clinical trial protocols?

    Many clinical trial protocols are impossible to execute as they are designed by employees of pharma/biotech and few external experts without any feedback from end users. At Transparency Life Sciences we decided to open up the design process and involve researchers, patients and physicians who treat them via Protocol Builder. Our initial results are very encouraging. You can try it yourself at http://transparencyls.com/

  • What method(s) can be used to determine LNG cost versus CO2 emissions charge?

    Specific cost for CO2 capture provides a parameter that can be used for comparison with capture systems across different industries and varying scales. Specific costs tend to be reported as CO2 captured and CO2 avoided. Most LNG plants discharge CO2 without considerations to capture. The environment becomes the receiver and its attendant adverse effects.

  • Richard Lasker added an answer in Lipid Extraction:
    Does anyone know of a lipids extraction of mouse brain protocol? Is it possible to do this despite the fixing of brain?

    I would like to extract free fatty acids, to analyze resolvins (lipid mediators which resolve inflammation) on mouse brain sections. And these brains were fixed in PFA. After fixation, the mouse brain are keep in cryoprotector medium at -20°C. After lipids extract, I would like to see resolvin with enzyme immunoassay.

    Richard Lasker · Brabant Research, Inc.

    Depends on the polarity of the lipid being extracted. I suggest searching for similarities with these methods:

    Folch method

    Bligh & Dyer method

    If you have Thin-layer chromatography available to you it too can separate lipids by weight.

    Remember; there is a wealth of SPE  methodology available from manufacturers websites.

  • Artur Banaszak added an answer in Catholicism:
    What is the role of the Catholic Church in particular in the formation of social attitudes in your countries?

    The social attitude, represented by a person, is built of many different factors. It seems to me that the impact on how we function within society depends also on our religious beliefs. There is something what is call “the social teaching of the Catholic Church”. Is this teaching present or known in your countries or local communities? Do you think that religion, particularly teaching of the Catholic Church, has any influence or impact on the social attitudes? In your opinion, religions, churches or other religion organizations should only take care of the spiritual matters or also, they should be interested in material world and they should be interested in the fate of ordinary people? Should religion organization speak out about social problems? How this situation looks in your countries? What you and what people in your surroundings think about this matter?

    Artur Banaszak · Wyzsza Szkola Gospodarki Euroregionalnej w Jozefowie

    I also live in the democratic country. I understand that " no one religion can dictate what the state must do, nor may the state intervene in church matters". But, the Constitution of my country and the European Union law guarantee me "freedom of religion and freedom of speech and express my believes. Freedom of religion does not mean that I cannot talk about my religion and promote the values of my religion. I do not want to press anyone to be Catholic and I do not want anybody to live according to my believes. I believe in God but also I am convinced to the tolerance. I care for all people no matter their religion or believes. I want to respect the believes of all people, even they may be different from mine.
    But, the values and principles taught by Christ, and then by the Church (charity, respect for human dignity, respect for human life from conception to natural death, love of peace, care for the poor and the weak, justice, etc) are very universal. Those values are written down in the Constitutions of many countries. And I think that everyone should live according to them no matter what is his or her religion and no matter if he or she believe in God or not. We are talking here about value that make world better.

  • How does acting "under the lights" affect an actor's performance as compared to acting during rehearsals?

    As an actor in my first collegiate play, I noticed that my acting ability and confidence were enhanced while performing under the lights during a public performance.

    Have other actors noticed the same? Is there any research that you know about that would "shed some light" on this phenomenon I experienced? 

    Aleid Yvonne de Jong · Universiteit Utrecht

    I definitely agree with William Rennie. Performing in a public performance is not only about performing under 'the lights', but also about the presence of the audience. Although I think that an actor is aware of the presence of the audience when he or she is acting, I do think that it's necessary to stay focused on the personage that is being played. Therefore an actor should let go of the awareness of the presence of an audience. To do this, one needs to have a stronger focus than during a rehearsal. Not being focused comes with a risk; a risk of making a mistake such as speaking out the wrong sentence. There is no room for thinking, doubting or improving, this is the 'moment supreme' - the moment when everybody in the play shows the outcome of their rehearsals. This comes with the realization of the actor that it has to perform 'at once'. I could compare it with choosing between ice cream flavors under time pressure: you'll make a more random but often more resolute decision than when you would have had plenty of time to choose. The same goes for performing. You cannot stutter and stammer, but you'll have to 'speak out loud' (I am aware of the fact that one can also act without speaking, this is just an example) and make the best of what you have learned so far. 

    You might be interested in a text of Mieke Bal: 'Performance and Performativity'. In this text Bal makes a distinction between performance and performativity, She also goes into the term 'speech act' to illustrate this. 

    All the best,

    Aleid 

  • Barry Hindess added an answer in Democracy:
    How would you define democratic innovation?

    "Democratic innovation" or "innovative democracy" is a new field of political research. But is it more than the rethinking of old concepts of participatory democracy?

    Barry Hindess · Australian National University

    I suspect that the original question as concerned with the question of how to be sure that a change in existing arrangements would actually make them more democratic. If this is the case, there is no point in seeking for an abstract definition of democratic innovation. What makes something seem to be more democratic will depend on what features of existing arrangements are seen asobstacles or limitations to democracy: removing some of those limitations would then be an improvement

  • Manuel Gensler added an answer in Sensing:
    Is there a simple method to characterize the force constant and quality factor of a particular AFM cantilever working in tapping mode?

    We are exploring a novel technique for AFM sensing, where we do sense drag in tapping mode but need to convert it into amplitude. We understand we need to characterize the cantilever mechanical parameters (essentially, I understand force constant K and quality factor Q). However, when purchasing one cantilever typically specs loosely speak of parameters and are such imprecise as 10 to 130, so no reliable force to displacement conversion may be done in practice.

    Is there any provider of fully characterized cantilevers? Is there any simple method for cantilever characterization, or a drag-to-displacement model well established not sensitive to changes in the mechanical parameters of the cantilever?

    Thanks in advance!

    Manuel Gensler · Humboldt-Universität zu Berlin

    Typical probe parameters given by the supplier are simply calculated from average cantilever dimensions and the elastic modulus. As you noticed, this values spread as much as the uncertainties in probe production. 

    Characterization of vertical cantilever sensitivity and spring constant is state of the art the "thermal noise" or "equipartition method" is most famous among. Depending on which literature you refer to, the uncertainty varies from 20% to 5% (http://www.physics.uwo.ca/~hutter/calibration/afmcal.html and reference below). The error can be strongly reduced by using state-of-the-art laser doppler vibrometry (LDV). Bruker offers tipless probes calibrated by this method for usage with the reference cantilever method (http://www.brukerafmprobes.com/p-3242-clfc-nobo.aspx). 

    Calibration of lateral spring constants is still challenging. You may use Sader's method on rectangular probes (http://www.ampc.ms.unimelb.edu.au/afm/calibration.html), but still have to determine the lateral sensitivity (http://repository.upenn.edu/cgi/viewcontent.cgi?article=1084&context=meam_papers). 

  • Ru-Jeng Teng added an answer in QIAGEN:
    Can I use Qiagen kits and primers in an Applied Biosystems Real Time PCR machine?

    Hi, my lab has an Applied Biosystems Real Time PCR, but I only have worked with Qiagen kits for PCR and primers. Are there any issues regarding using Qiagen kits with Applied PCR machine?

    Ru-Jeng Teng · Medical College of Wisconsin

    There should be no problem. The machine only changes the temperature and using a sensor to detect the fluorescence. Unless you are using a fluorphore that can not be detected by the machine there should be no problem.

  • Zainub Jooma added an answer in Delirium:
    How often do you see emergence delirium post-anesthesia in children?

    Emergence delirium in the post-anesthetic care unit as defined by any scoring method used by your institution.

    Zainub Jooma · Johannesburg Hospital

    We are using the PAED score as described by Sikich and Lerman, with a threshold score >= 10 as an indicator of delirium.

  • Are current DES (e.g. Promus, Xience V or Integrity) available in Iran ?

    If yes, what do they cost? I would like to know how much newer generation DES are in Iran.

    Alexander Sedaghat · University of Bonn

    dear mr moohebati,

    thank you very much!!

  • Ravindra Kailasrao Zirmire added an answer in DAPI:
    What could be a possible reason if the dermal fibroblasts are not getting detached from the plate even after the trypsinization?

    Actually we are looking for the effect of some chemicals on fibroblast and in one of the treatment the newborn dermal fibroblasts are not getting detached from the plate. But in the same conditions in the control i.e. without treatment the cells got detached in two minutes. But in chemical treated condition they are not even changing their morphology at all after the same time of trypsinization. And after staining them with DAPI they are totally fine with prominent nuclei (not dead cells just attached to the plate).

    Ravindra Kailasrao Zirmire · Institute for Stem Cell Biology and Regenerative Medicine

    Hello Dorothy,

    Yes I checked the cells by trypan blue staining also they are not getting stained. And in nuclear staining I saw some ells are showing the characters of apoptosis i.e. the some cells are showing nuclear blebbing.

  • Javaid I Qazi asked a question in Sintering:
    How to determine Particle size in porous sintered PM parts?

    I am interested in determining particle size of powder used to make a porous PM part. Particles are on the scale of 100nm to a few um. Does anyone in the group have thoughts how to go about it other than doing SEM followed by extensive image ... the material has lots of porosity and I am interested in getting the size of the particles in it.

    thanks in advance.

  • Younes BOUALLEGUI added an answer in Protocols:
    Can anyone give me suggessions about qRT-PCR?

    I would like to know if the reverse transcription reaction influence or not the DNA expression, in other way I would say which appropriate protocol to convert RNA to DNAc for real time PCR reaction, because i found many protocol with different time of incubation, could you suggest good and not expensive one, Regards.

    Younes BOUALLEGUI · University of Carthage

    Thanks a lot Nadine. Best wishes, Younes

  • Awajiogak Anthony Ujile added an answer in FDM:
    How can I solve the Modified Bessel PDE using FEM?

    I am attempting to solve a modified bessel partial differential equation using a finite element implementation. I have used FDM (with reasonable success) and was hoping to replicate the results using FEM. My exposure to FEM is limited and I was hoping a commercial suite (such as Matlab or Mathematica) could solve this problem. My problem is defined as such - 

    u(r,t)=0 at t=0 and r=0

    du/dr=k1*u(r,t) at r==1  where k1 is a constant

    d2u/dr2 +1/r*du/dr - u/r^2 = du/dt +r/2*k2, where k2 is a constant

    u and u(r,t) are interchange-able in notation

    My question is - is this problem solvable using an FEM toolbox?

    Many thanks. RM

    Awajiogak Anthony Ujile · Rivers State University of Science and Technology

    Modified Bessel function PDE can be solved with FEM. The boundary conditions should be adequately defined and the application of MATHCAD can be of help. Reference to MATHCAD software tool/guide should be made to direct you. Experts in the use of the tool can help you.